9
Research Article Cephalometric Investigation of First Cervical Vertebrae Morphology and Hyoid Position in Young Adults with Different Sagittal Skeletal Patterns Seher Gündüz Arslan, 1 Neval DildeG, 2 and Jalen Devecioglu Kama 3 1 Department of Orthodontics, Faculty of Dentistry, University of Dicle, 21280 Diyarbakır, Turkey 2 Private Practice, Elazı˘ g, Turkey 3 Private Practice, Izmir, Turkey Correspondence should be addressed to Seher G¨ und¨ uz Arslan; [email protected] Received 19 June 2014; Accepted 14 July 2014; Published 24 July 2014 Academic Editor: Serdar ¨ Us ¸¨ umez Copyright © 2014 Seher G¨ und¨ uz Arslan et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. e aim of this retrospective study was to examine hyoid bone position and C1 (atlas) morphology in males and females and analyze these parameters with respect to different sagittal skeletal patterns via cephalometry, with the goal of identifying cephalometric norms. Lateral cephalometric radiographs from 120 individuals (average age: 21.1 ± 2.9 years) were classified according to their ANB angle (Class I, II, or III) and used to assess 14 parameters. Class I and II patients showed significant differences in Hy-NSL, Hy-PD, Hy-CVT, Lum, and a-p measurements. ese parameters were consistently larger in males than in females. Intergroup comparisons among males showed significant differences in the SNA, ANB, Hy-CVT, X, and Z measurements. e hyoid was positioned more inferiorly and anteriorly and was more prominent in males than in females in all groups. Among participants exhibiting a Class I skeletal pattern, C1 was also larger in the anterior-posterior direction in males than in females. In the sagittal plane, the hyoid was positioned similarly in males with either Class I or III skeletal patterns but was positioned posteriorly in males with a Class II skeletal pattern. In addition, the vertical position of C1 varied with sagittal skeletal pattern in males. 1. Introduction e head and neck have a balanced relationship similar to a lever-and-pivot system, with its fulcrum at the level of the occipital condyle. To maintain an upright position, muscles exert equal but opposing anterior and posterior forces on the occipital condyles [1] such that the head remains balanced over the first cervical vertebra (C1), also known as the atlas. C1 is an irregular ring-shaped bone made up of two lateral masses joined at the front and back by the short anterior and long posterior arches [2]. Importantly, no intervertebral disk develops between the atlas and the second cervical vertebra (C2), the axis [3]. Because the atlas represents the transition between the skull and the axial skeleton, it is of particular interest in orthodontics [4], and it is thought that the dimensions of this vertebra affect aspects of both the facial skeleton and the cervical column [5]. For example, variation in the dimensions of C1, as well as head and neck posture, were associated with differences in craniofacial morphology involving the cranial base [48], the upper airway space [9], occlusion [4], and temporomandibular disorders [10, 11]. Treuenfels [12] observed that the inclination of the atlas is associated with sagittal jaw position in that the anterior arch of the atlas shows a more cranial position in progenic compared to orthogenic patients. Changes in head posture [13, 14] and changes in the inclination of the mandible [15] also influence the position of the hyoid bone. e hyoid, which is positioned between the mandibular symphysis and the larynx in the front of the neck, joins together the tongue, mandible, cranial base, sternum, scapula, thyroid cartilage, and pharynx and is influenced by these structures [16]. e hyoid bone has no bony articulation with any other bone but is instead suspended in the soſt tissue Hindawi Publishing Corporation e Scientific World Journal Volume 2014, Article ID 159784, 8 pages http://dx.doi.org/10.1155/2014/159784

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Research ArticleCephalometric Investigation of First Cervical VertebraeMorphology and Hyoid Position in Young Adults with DifferentSagittal Skeletal Patterns

Seher Guumlnduumlz Arslan1 Neval DildeG2 and Jalen Devecioglu Kama3

1 Department of Orthodontics Faculty of Dentistry University of Dicle 21280 Diyarbakır Turkey2 Private Practice Elazıg Turkey3 Private Practice Izmir Turkey

Correspondence should be addressed to Seher Gunduz Arslan agseherhotmailcom

Received 19 June 2014 Accepted 14 July 2014 Published 24 July 2014

Academic Editor Serdar Usumez

Copyright copy 2014 Seher Gunduz Arslan et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

The aim of this retrospective study was to examine hyoid bone position andC1 (atlas)morphology inmales and females and analyzethese parameters with respect to different sagittal skeletal patterns via cephalometry with the goal of identifying cephalometricnorms Lateral cephalometric radiographs from 120 individuals (average age 211plusmn 29 years) were classified according to their ANBangle (Class I II or III) and used to assess 14 parameters Class I and II patients showed significant differences in Hy-NSL Hy-PDHy-CVT Lum and a-pmeasurementsThese parameters were consistently larger inmales than in females Intergroup comparisonsamong males showed significant differences in the SNA ANB Hy-CVT X and Z measurements The hyoid was positioned moreinferiorly and anteriorly and was more prominent in males than in females in all groups Among participants exhibiting a ClassI skeletal pattern C1 was also larger in the anterior-posterior direction in males than in females In the sagittal plane the hyoidwas positioned similarly in males with either Class I or III skeletal patterns but was positioned posteriorly in males with a Class IIskeletal pattern In addition the vertical position of C1 varied with sagittal skeletal pattern in males

1 Introduction

The head and neck have a balanced relationship similar to alever-and-pivot system with its fulcrum at the level of theoccipital condyle To maintain an upright position musclesexert equal but opposing anterior and posterior forces on theoccipital condyles [1] such that the head remains balancedover the first cervical vertebra (C1) also known as the atlasC1 is an irregular ring-shaped bone made up of two lateralmasses joined at the front and back by the short anterior andlong posterior arches [2] Importantly no intervertebral diskdevelops between the atlas and the second cervical vertebra(C2) the axis [3]

Because the atlas represents the transition between theskull and the axial skeleton it is of particular interest inorthodontics [4] and it is thought that the dimensions ofthis vertebra affect aspects of both the facial skeleton and the

cervical column [5] For example variation in the dimensionsof C1 as well as head and neck posture were associatedwith differences in craniofacial morphology involving thecranial base [4ndash8] the upper airway space [9] occlusion [4]and temporomandibular disorders [10 11] Treuenfels [12]observed that the inclination of the atlas is associated withsagittal jaw position in that the anterior arch of the atlas showsa more cranial position in progenic compared to orthogenicpatients

Changes in head posture [13 14] and changes in theinclination of the mandible [15] also influence the position ofthe hyoid bone The hyoid which is positioned between themandibular symphysis and the larynx in the front of the neckjoins together the tongue mandible cranial base sternumscapula thyroid cartilage and pharynx and is influenced bythese structures [16]The hyoid bone has no bony articulationwith any other bone but is instead suspended in the soft tissue

Hindawi Publishing Corporatione Scientific World JournalVolume 2014 Article ID 159784 8 pageshttpdxdoiorg1011552014159784

2 The Scientific World Journal

via ligaments and muscles [17] The function of this structureis to maintain the positional balance of the respiratorypassage as well as respiratory sufficiency by anchoring thetongue It also has an important role in tongue function andin maintaining an upright head position and cranial balance[18] Because of its unique structure the position of thehyoid bone changes with head posture and body position andmoves during various oral functions in close association withtongue activity [19 20]Without the hyoid the position of thehead could not be maintained with the same degree of finecontrol [21]

In the literature it has been shown that changes inmandibular position are related to hyoid bone changesand that the hyoid position adapts to anterior-posteriorchanges in head posture [22ndash24] Furthermore studies onthe relationship between the hyoid and the facial skeletonand cervical column have indicated that the hyoid-cervicalrelationship is more stable than the relationship of the hyoidto the skull and mandible [22 25 26] Consequently studiesexamining different malocclusions can reveal the role of thehyoid bone in the dentofacial system and the response ofmandibular development to these malocclusions

Modern orthodontics studies dentomaxillofacial struc-tures including the head and neck When examining thesestructures and their relationships with one another theposition of hyoid bone with respect to other structuresbecomes important especially for preventing relapse afterorthodontic and orthognathic surgical treatment Accord-ingly the aim of this retrospective study was to examinehyoid bone position and C1 (atlas) morphology in males andfemales and analyze these parameterswith respect to differentsagittal skeletal patterns via cephalometry with the goal ofidentifying cephalometric norms

2 Methods

A total of 120 patients (60 males 60 females age average211 plusmn 29 years) who attended Dicle University Faculty ofDentistry Clinic ofOrthodontics forOrthodontic Treatmentparticipated in the present studyThe subject participation inthis study was retrospectively selected among patients thatindicate skeletal Cl I II and III relationshipThe radiographicdata included lateral cephalometric radiographs The criteriafor selection of patientsrsquo radiographs had to be of high qualityand sharpness and all radiographs had to be taken by thesame apparatus and same technician with patients in naturalhead posture Natural head posture was determined by usinga fluid level method as described by Showfety et al [27]

The patients were divided into three groups (Cl I IIand III) 119899 = 40 (119899 = 20 female 119899 = 20 male) sub-jects each according to a widely used indicator of skeletalanterior-posterior discrepancies known as the ANB angleThe ANB angle refers to the angle opened between theA-point the nasion and the B-point on a cephalographThis value was used by Steiner [28ndash30] as means to groupparticipants according to skeletal class Class I ANB = 2ndash4∘Class II ANB gt 4∘ and Class III ANB lt 2∘ In additioneach group was divided into subgroups according to sex

Table 1 Description of landmarks

Landmark Definition

Nasion (N) Most anterior point of the frontonasalsuture

Sella (S) Center of the sella turcica

Articulare (Ar)

Point of intersection between theposterior border of the mandibular ramusand the inferior border of the posteriorcranial base

Spina nasalisanterior (ANS)Spina nasalisposterior (PNS)

Pogonion (Pog) Most anterior point on the mandibularsymphysis

Gnathion (Gn) Most anterior-inferior point on themandibular symphysis

Menton (Me) Most inferior point on the mandibularsymphysis

Hyoid (Hy) Most superior-anterior point on the bodyof the hyoid bone

Hyoid1015840 (Hy1015840) Most superior-posterior point on thegrater horn of hyoid bone

CV4ip Most poster-inferior point on the corpusof the fourth cervical vertebra

CV2tg Most superior-posterior point on thecorpus of the fourth cervical vertebra

Table 2 Description of lines

Line Definition

CVT (the upper part ofthe cervical spine)

Line through CV2tg and CV4ipin the upper part of the cervicalspine

NSL (nasion-sella line) The nasion-sella line throughpoints N and S

NL (nasal line) The line through ANS and PNS

ML (mandibular line)The mandibular line tangentialto the lower border of themandible through Gn

Hy-Hy1015840 (hyoid line) The hyoid line passing throughHy and Hy1015840

(20 subjects each) All participants enrolled in this studyshowed normal vertical skeletal patterns (SNGoMe = 28ndash36∘) had not previously undergone orthodontic treatment ororthognathic surgery showed no visual hearing breathingor swallowing disorders and had no respiratory disturbanceor any other trauma affecting the craniofacial region

All cephalometric tracings were performed by the sameperson (SGA) using 003 mm matte acetate paper witha 3H pencil Eleven linear measurements were performedas described by Ceylan [31] Based on the landmarks andlines defined in Tables 1 and 2 respectively a total of 14angular and linear measurements were assessed as describedin Table 3 The cephalometric landmarks and measurementswere shown in Figures 1 and 2

The Scientific World Journal 3

Table 3 Description of linear measurements

Landmark Definition

Hy-NSL Linear distance from H along a perpendicularto NSL

Hy-NL Linear distance from H along a perpendicularto the NL

Hy-Hy1015840ML Linear distance from hyoid line to mandibularline

Hy-CVT Linear distance from H along a perpendicularto CVT

Hy-Pog The linear distance between H and pogonionHy-Me The linear distance between H and menton

119883

Distance between inferior border of theoccipital bone and dorsal arch of first cervicalvertebrae

119884Distance between most superior and inferiorpoints of first cervical vertebraersquos dorsal arch

119885

Distance between most inferior point of firstcervical vertebraersquos dorsal arch and mostsuperior point of second cervical vertebraersquos(axis) spinal process

Lum

Distance between anterior border of the firstcervical vertebraersquos dorsal arch and posteriorborder of the second cervical vertebraersquosodontoid process

a-pDistance between first cervical vertebraersquos mostfrontal point of tuberculum anterior and mostposterior point of dorsal arch

Two weeks after the first measurements 30 radiographswere selected at random and remeasured and a correlationanalysis was performed using data from the first and secondmeasurements Differences observed between the first andsecond measurements were not significant (119875 gt 005)

All statistical analyses were performed using the Statisti-cal Package for Social Sciences version 100 (SPSS ChicagoIllinois USA) Gender differences among groups were ana-lyzed using paired-sample t-tests Mean differences amonggroups were examined by analysis of variance (ANOVA) forrepeated measures with a post hoc least significant difference(LSD) test for multiple comparisonsThe level of significancefor all analyses was set at 119875 lt 005

3 Results

Intragroup (male versus female participants) and intergroupcomparisons of differences between different skeletal patternsare shown in Tables 4 5 and 6 Intragroup comparison ofClass I male and female participants revealed statisticallysignificant differences in the Hy-NSL (119875 lt 0001) Hy-PD(119875 lt 0001) Hy-CVT (119875 lt 0001) 119883 (119875 = 0004) 119884 (119875 =0012) Lum (119875 = 0013) and a-p (119875 = 0001) measurementsAlthough the hyoid bone was positioned more inferiorlyand anteriorly in males than in females with Class I skeletalpatterns the dimensional measurements for C1 revealed thatthis vertebra was larger and positioned lower in males Inthe intragroup comparison ofClass II participants significant

Top

CV2tg

CV4ip

Go

PNS

S N

AANS

MeGn

BPog

Ar

HyHy998400

Figure 1 Angular and linear measurements used

Top

CV2ap

Ar

Lum

X

Y

Z

Figure 2 Linear measurements on the first cervical vertebrae

differences were observed for Hy-NSL (119875 = 0006) Hy-NL(119875 = 0050) and Hy-CVT (119875 = 0001) The measurementsHy-NSL (119875 lt 0001) Hy-NL (119875 = 0003) Hy-CVT (119875 lt0001) Lum (119875 = 0027) and a-p (119875 = 029) alsoshowed statistically significant differences in the intragroupcomparison for Class III participants All measurements weregreater inmagnitude formale versus female participantsThehyoid was positioned more inferiorly and anteriorly in maleswith Class II and Class III skeletal patterns In addition C1was larger in the anterior-posterior direction in males versusfemales with Class III skeletal patterns

Intergroup comparison showed statistically differences inthe SNA ANB Hy-CVT 119883 and 119885 measurements in maleparticipants In addition SNA showed statistically significantdifferences between Class II and Class III participants (119875 =0006) and between Class I and Class III participants (119875 =0003) ANB also revealed statistically significant differencesamong all groups (119875 lt 0001) Hy-CVT showed statis-tically significant differences between Class I and Class IIparticipants (119875 = 0019) The 119883 and 119885 measurements weresignificantly different between Class I versus Class III (119875 =0010) and Class II versus Class III (119875 = 0004) participantsrespectively The hyoid was positioned more posteriorly inparticipants with Class II skeletal patterns compared to thosewith Class I skeletal patterns In addition the posterior part

4 The Scientific World Journal

Table4Intragroup

comparis

onof

malea

ndfemalep

artic

ipants

Measurements

ClassI

ClassII

ClassIII

Female(119899=20)

Male(119899=20)

(119875value)

Female(119899=20)

Male(119899=20)

(119875value)

Female(119899=20)

Male(119899=20)

(119875value)

Mean

SDMean

SDMean

SDMean

SDMean

SDMean

SDSN

A(∘ )

8080

446

8360

503

0268

NS

8330

539

8337

381

0858

NS

7900

485

7677

435

0434

NS

SNB(∘ )

7790

448

8040

485

0053

NS

7660

560

7643

335

0858

NS

8080

391

7888

416

0510

NS

ANB(∘ )

290

128

320

101

0240

NS

670

067

693

104

0776

NSminus18

0204

minus211

078

0127

NS

HyHy1015840MD(∘ )

770

537

540

291

0424

NS

840

389

1175

954

0624

NS

840

537

1177

993

0624

NS

Hy-NSL

(mm)

10370

427

12060

791

000

0lowastlowastlowast

10560

554

11887

1052

000

6lowastlowast

10600

522

11966

756

0001lowastlowast

HyNL(m

m)

5950

467

7110

667

0001lowastlowast

6350

667

7162

930

0050lowast

6210

508

7177

624

0003lowastlowast

Hy-CV

T(m

m)

4940

279

5930

266

000

0lowastlowastlowast

5020

278

5612

164

0001lowastlowast

4990

268

5866

327

000

0lowastlowastlowast

HyPo

g(mm)

5490

818

5110

360

0196

NS

5160

356

5025

647

096

4NS

5190

540

4977

591

0566

NS

HyMe(mm)

4910

724

4360

368

0063

NS

4440

394

4275

625

0562

NS

4520

431

4366

593

0623

NS

119883(m

m)

800

163

1170

262

000

4lowastlowast

860

195

937

287

0743

NS

910

213

822

263

0677

NS

119884(m

m)

830

125

1040

171

0012lowast

870

149

975

237

0470

NS

850

143

966

122

0077

NS

119885(m

m)

700

221

730

226

0908

NS

650

241

587

241

0369

NS

780

147

911

161

0086

NS

LUM

(mm)

2790

272

3120

229

0013lowast

284

222

2987

285

0227

NS

2900

309

3400

683

0027lowast

a-p(m

m)

4690

185

5190

246

0001lowastlowast

4850

201

5075

399

0192

NS

4740

241

4988

664

0029lowast

lowast

119875lt005lowastlowast

119875lt001lowastlowastlowast

119875lt0001NSno

nsignificantSD

stand

arddeviation

and119899num

bero

fpatients

The Scientific World Journal 5

Table 5 Intergroup comparison of mean differences among males with Class I II and III skeletal patterns

Measurements Class I (119899 = 20) Class II (119899 = 20) Class III (119899 = 20) ANOVA Multiple comparison LSD test (119875 value)Mean SD Mean SD Mean SD CI-CII CII-CIII CI-CIII

SNA (∘) 8360 503 8338 381 7678 435 lowastlowast 0917 0006 0003SNB (∘) 8040 485 7644 335 7889 416 NS 0060 0245 0445ANB (∘) 320 131 694 114 minus211 078 lowastlowastlowast 0000 0000 0000Hy Hy1015840 MD (∘) 540 291 1175 954 1178 993 NS 0104 0994 0092Hy NSL (mm) 12060 791 11888 1052 11967 756 NS 0678 0852 0816Hy NL (mm) 7110 667 7162 930 7178 624 NS 0883 0967 0844Hy-CVT (mm) 5930 266 5612 164 5967 227 lowast 0019 0060 0608Hy Pog (mm) 5110 360 5025 647 4978 591 NS 0741 0858 0596Hy Me (mm) 4360 368 4275 625 4367 593 NS 0739 0726 0978119883 (mm) 1170 262 938 287 822 263 lowast 0082 0389 0010119884 (mm) 1040 171 975 237 967 122 NS 0454 0925 0384119885 (mm) 730 226 588 241 911 161 lowast 0169 0004 0075LUM (mm) 3120 230 2988 285 3400 683 NS 0537 0069 0185a-p (mm) 5190 247 5075 399 4989 664 NS 0607 0707 0356lowast

119875 lt 005 lowastlowast119875 lt 001 lowastlowastlowast119875 lt 0001 NS statistically not significant SD standard deviation and 119899 number of patients

Table 6 Intergroup comparison of mean differences among females with Class I II and III skeletal patterns

Measurements Class I (119899 = 20) Class II (119899 = 20) Class III (119899 = 20) ANOVA Multiple comparison LSD test (119875 value)Mean SD Mean SD Mean SD CI-CII CII-CIII CI-CIII

SNA (∘) 8080 446 8330 539 7900 485 NS 0266 0061 0421SNB (∘) 7790 448 7660 56 8080 391 NS 0895 0072 0094ANB (∘) 290 128 670 067 minus180 104 lowastlowastlowast 0000 0000 0000Hy Hy1015840 MD (∘) 770 537 840 389 840 537 NS 0753 1000 0753Hy NSL (mm) 10370 427 10560 554 10600 522 NS 0407 0861 0317Hy NL (mm) 5950 467 6350 667 6210 508 NS 0118 0577 0304Hy-CVT (mm) 4940 279 5020 278 4990 268 NS 0522 0809 0688Hy Pog (mm) 5490 818 5160 356 5190 540 NS 0231 0912 0275Hy Me (mm) 4910 724 4440 395 4520 431 NS 0061 0742 0117119883 (mm) 800 163 860 195 910 213 NS 0490 0565 0211119884 (mm) 830 125 870 149 850 143 NS 0527 0751 0751119885 (mm) 700 221 65 241 78 147 NS 0594 0172 0396LUM (mm) 2790 272 284 222 2900 309 NS 0682 0624 0371a-p (mm) 4690 185 4850 201 4740 241 NS 0101 0253 0600lowastlowastlowast

119875 lt 0001 NS statistically not significant SD standard deviation and 119899 number of patients

of C1 was positioned more inferiorly among participantswith Class I versus Class III skeletal patterns C1 was alsocloser to C2 among participants of Class II versus ClassIII skeletal patterns In contrast the intergroup comparisonamong female participants revealed a significant difference inonly the ANB measurement among the groups

4 Discussion

The position of the hyoid bone is of great clinical interestbecause it plays an important role in maintaining the dimen-sions of the upper airway and an upright natural head posture

[26 32 33] The first cervical vertebra also known as theatlas represents the transition between the skull and the axialskeleton and it is reported that the dimensions of this vertebraaffect aspects of both the facial skeleton and the cervicalcolumn [34] Numerous previous studies have shown thatorthodontic treatments impacting mandibular position canalso alter the position of the hyoid given that it is attachedto the mandible via the geniohyoid anterior digastric andmylohyoid muscles [35ndash37]

Graber [18] evaluated the position of the hyoid in 30children (16 males and 14 females mean age of 6 years) afterorthopedic treatment for mandibular prognathism Graberobserved that the hyoid position had shifted posteriorly

6 The Scientific World Journal

and inferiorly at 3 years after treatment Surucu et al [38]examined 10 individuals with skeletal Class II division Imalocclusions and found that after the activator was appliedand the bite was opened the tongue shifted posteriorly andcaused constriction of the upper airway To compensate forthis constriction patients would need to alter their normalupright head posture by extending the headjawThe authorsreported that as a result of these changes the mandiblemoved into a more anterior position while the hyoid shiftedanteriorly depending on the degree of head extension It hasbeen reported that the hyoidmoves posteriorly and inferiorlyin mandibular setback surgeries [39 40] This subsequentlyresults in the base of the tongue shifting posteriorly andinferiorly resulting in constriction of the upper airway andforcing the patient to further extend the head positionto lengthen the upper airway Posterior movement of themandible can cause relaxation of the suprahyoidmusculaturewhich may instigate balance disorders in the head and neckmuscles and oropharyngeal complex It has been postulatedthat if this relaxation continues for an extended period it canalter the position of the hyoid as well as the length of thesuprahyoid muscle causing skeletal relapse [41]

Cephalometric radiography one of the most importanttools in orthodontics both clinically and in research permitsthe accurate evaluation of the dental skeletal and soft tissuerelationships of the craniofacial complex before the initiationof treatment and during growth [42ndash44]

In light of this information the aim of this study wasto document the position of the hyoid bone and cervicalatlas morphology on the cephalometric radiographs of par-ticipants with different sagittal skeletal patterns with the goalof identifying cephalometric norms To achieve this partic-ipants were classified according to horizontal discrepanciesobserved in the ANB angle a parameter that is widely usedin the evaluation of skeletal anterior-posterior relationships[45ndash47] Previous studies have shown that natural headposture is related to respiratory [48] and visual function[49] Therefore to determine natural head posture in aprecise manner only individuals without visual hearing orrespiratory disturbances were included in this study

Our results from the intragroup comparison of Class Iand Class II participants revealed that several measurementswere significantly larger in males than in females Theseincluded Hy-NSL (119875 lt 0001) Hy-PD (119875 = 0001) andHy-CVT (119875 lt 0001) In addition the hyoid was positionedmore anteriorly and inferiorly in males than in femalesSahin Saglam and Uydas [50] investigated variation in hyoidposition and head posture between genders (38 females and38 males) using lateral cephalometric films obtained using anatural head position All participants had a Class I skeletalpattern and ideal dental occlusion The authors found thatnatural head position did not differ between genders but thehyoid bone was positioned more superiorly and posteriorlyin females compared to males Ceylan [51] examined 90adolescents including 45 boys and 45 girls aged 13ndash15 yearsand analyzed the relationship of the ANB angle and naturalhead position to the position of the hyoid bone Naturalhead position was not significantly affected by gender butthe hyoid bone was positioned significantly more superiorly

and posteriorly in females than in males These results areconsistent with the data reported here

In the intragroup comparison of Class I participantssignificant differences were observed with respect to the 119883119884 Lum and a-p parameters all of which were smaller infemales The data also revealed a greater superior-posteriorarea of C1 shorter distance between C1 and C2 shorteranterior-posterior dimensions and shorter distance betweenthe anterior border of the C1 dorsal arch and the posteriorborder of the C2 odontoid process also in females Theseresults suggest that the male body is more developed than thefemale body

In the intragroup comparison of Class III participantsit was found that the hyoid bone was positioned moreanteriorly and inferiorly in males than in females Cervicaland craniocervical posture may be one factor explaining thesignificant differences observed between males and femaleswho have Class III malocclusions [24] Females who haveClass III malocclusions show amuchmore ldquonormalrdquo positionof the hyoid bone as compared to males with Class IIImalocclusions This may be due to heightened aestheticawareness of a prognathic mandible in girls which leadsthem to assume quite early in life a modified head postureallowing them to minimize the appearance of a prominentchin

Intergroup comparisons of differences between gendersshowed statistically significant differences in ANB measure-ments in all groups These results are unsurprising giventhat participants with normal vertical patterns and differentANB values were included in this study In the intergroupcomparison of males the Hy-CVT distance was found to begreater in Class I than in Class II participants This indicatespronounced anterior positioning of the hyoid bone in Class Imales On the other hand Ceylan [31] evaluated the hyoidbone position in different skeletal patterns of adolescentsaged 13ndash15 years and reported that the hyoid bone waspositionedmore anteriorlywith an increase in theANBangleThis is in direct contrast to our study whichmay be the resultof examining different age groups (adolescents versus youngadults) and the inclusion of participants with normal verticalskeletal patterns in our work Dincer et al [52] investigatedthe position of the hyoid bone with respect to its relationshipwith the dentofacial system in 45 participants with ClassI Class II division I and Class III malocclusions It wasascertained that the hyoid was positioned more posteriorlyamong participants with a Class II division I skeletal patterncompared to a Class I pattern and more anteriorly amongparticipants with a Class III skeletal pattern compared toa Class I pattern In addition the greater 119883 values amongClass I versus Class III participants indicate an overall lowerposition of C1 in the Class I group Class III participants hadhigher 119885 values compared to the Class II group accordinglythe distance between the posterior part of C1 andC2 is greaterin Class III versus Class II participants

Regarding skeletal patterns in female participants no dif-ference was observed for parameters relating to the hyoid orC1 indicating nomorphological difference in these structuresamong females Consistent with our findings Adamidis andSpyropoulos [24] found no statistically significant differences

The Scientific World Journal 7

in the position or orientation of the hyoid among femalesexhibiting Class I malocclusions versus those with Class IIImalocclusions

5 Conclusions

This study revealed that the hyoid bone is positioned moreinferiorly and anteriorly and is more prominent in malesthan in females regardless of variation in the axial skeletonC1 was also larger along the anterior-posterior axis in malesexhibiting a Class I skeletal pattern compared to females inthe same class However no significant difference in hyoidposition or C1 morphology was observed in relation to theANB in females In the sagittal plane the hyoid bone wassimilar in males with a Class I or Class III skeletal patternbut was positioned more posteriorly based on mandibularbone development in males with Class I skeletal patterns Inaddition the vertical position of C1 varied depending on thesagittal skeletal pattern among male participants

It is especially important among males that the hyoidbone remains in the same position after orthodontic andorthognathic treatment so that the balance of the soft tissuesis not altered thus reducing the chance of relapse Theresults of this study are therefore highly useful for clinicianswho must assess the stability of these structures in patientswho are candidates for orthognathic or orthopedic surgerywhich may help to prevent the obstruction of the upperairway In addition this study helps to identify cephalometricnorms that exist amongmales and females who have differentskeletal sagittal anomalies

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] A G Brodie ldquoEmerging concepts of facial growthrdquo AngleOrthodontist vol 41 no 2 pp 103ndash118 1971

[2] D K Bailey ldquoThenormal cervical spine in infants and childrenrdquoRadiology vol 59 no 5 pp 712ndash719 1952

[3] S W Gray C B Romanie and J E Skandalakis ldquoCongenitalfusion of the cervical vertebraerdquo Surgery Gynecology amp Obstet-rics vol 118 pp 373ndash385 1964

[4] J Huggare ldquoAssociation between morphology of the firstcervical vertebra head posture and craniofacial structuresrdquoEuropean Journal of Orthodontics vol 13 no 6 pp 435ndash4401991

[5] M Sandikcioglu S Skov and B Solow ldquoAtlas morphologyin relation to craniofacial morphology and head posturerdquoEuropean Journal ofOrthodontics vol 16 no 2 pp 96ndash103 1994

[6] E Hellsing J McWilliam T Reigo and E Spangfort ldquoTherelationship between craniofacial morphology head postureand spinal curvature in 8 11 and 15-year-old childrenrdquo EuropeanJournal of Orthodontics vol 9 no 4 pp 254ndash264 1987

[7] J Huggare ldquoA cross-sectional study of head posture andcraniofacial growth in children from the north of Finlandrdquo

Proceedings of the Finnish Dental Society vol 83 no 1 pp 5ndash15 1987

[8] J Huggare and P Houghton ldquoAssociations between atlantoaxialand craniomandibular anatomyrdquo Growth Development andAging vol 60 no 1 pp 21ndash30 1996

[9] A Wenzel E Hojensgaard and J M Henriksen ldquoCraniofacialmorphology and head posture in children with asthma andperennial rhinitisrdquo European Journal of Orthodontics vol 7 no2 pp 83ndash92 1985

[10] L Sonnesen M Bakke and B Solow ldquoTemporomandibulardisorders in relation to craniofacial dimensions head postureand bite force in children selected for orthodontic treatmentrdquoEuropean Journal of Orthodontics vol 23 no 2 pp 179ndash1922001

[11] C M Visscher W De Boer F Lobbezoo L L M H HabetsandMNaeije ldquoIs there a relationship between head posture andcraniomandibular painrdquo Journal of Oral Rehabilitation vol 29no 11 pp 1030ndash1036 2002

[12] H Treuenfels ldquoDie Relation von Atlasposition prognather undprogener Kieferanomalierdquo Fortschritte der Kieferorthopadie vol43 no 1 p 82 1982

[13] U Gustavsson G Hansson A Holmqvist and M LundbergldquoHyoid bone position in relation to head posturerdquo SwedishDental Journal vol 65 no 8 pp 423ndash430 1972

[14] J W Pim Valk A J J Zonnenberg C J van Maanen and OG T van Wonderen ldquoThe biomechanical effects of a sagittalsplit ramus osteotomy on the relationship of the mandible thehyoid bone and the cervical spinerdquo The American Journal ofOrthodontics and Dentofacial Orthopedics vol 102 no 2 pp99ndash108 1992

[15] A Tallgren and B Solow ldquoHyoid bone position facial mor-phology and head posture in adultsrdquo European Journal ofOrthodontics vol 9 no 1 pp 1ndash8 1987

[16] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo AmericanJournal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[17] G J Romanes Cunninghamrsquos Manual of Practical Anatomy vol3 Oxford University Press New York NY USA 14th edition1983

[18] L W Graber ldquoHyoid changes following orthopedic treatmentof mandibular prognathismrdquo Angle Orthodontist vol 48 no 1pp 33ndash38 1978

[19] KMHiiemae SMHayenga andA Reese ldquoPatterns of tongueand jawmovement in a cinefluorographic study of feeding in themacaquerdquo Archives of Oral Biology vol 40 no 3 pp 229ndash2461995

[20] J Spiro J K Rendell and T Gay ldquoActivation and coordinationpatterns of the suprahyoid muscles during swallowingrdquo Laryn-goscope vol 104 no 11 I pp 1376ndash1382 1994

[21] H Tsai ldquoThe positional changes of hyoid bone in childrenrdquoTheJournal of Clinical Pediatric Dentistry vol 27 no 1 pp 29ndash342002

[22] B Fromm and M Lundberg ldquoPostural behaviour of the hyoidbone in normal occlusion and before and after surgical correc-tion of mandibular protrusionrdquo Swedish Dental Journal vol 63no 6 pp 425ndash433 1970

[23] H Opdebeeck W H Bell J Eisenfeld and D MishelevichldquoComparative study between the SFS and LFS rotation as apossible morphogenic mechanismrdquo The American Journal ofOrthodontics vol 74 no 5 pp 509ndash521 1978

8 The Scientific World Journal

[24] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in Class I and Class III malocclusionsrdquo Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol101 no 4 pp 308ndash312 1992

[25] S Carlsoo and G Leijon ldquoA radiographic study of the positionof the hyo-Iaryngeal complex in relation to the skull and thecervical column in manrdquo Transactions Royal Schools DentistryStockholm and Umeft vol 5 pp 13ndash34 1960

[26] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo TheAmerican Journal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[27] K J Showfety P S Vig and S Matteson ldquoA simple method fortaking natural-head-position cephalogramsrdquo American Journalof Orthodontics vol 83 no 6 pp 495ndash500 1983

[28] C C Steiner ldquoCephalometrics for you and merdquo The AmericanJournal of Orthodontics vol 39 no 10 pp 729ndash755 1953

[29] C C Steiner ldquoCephalometrics in clinical practicerdquo The AngleOrthodontist vol 29 no 1 pp 8ndash29 1959

[30] C C Steiner ldquoThe use of cephalometrics as an aid to planningand assessing orthodontic treatment Report of a caserdquo TheAmerican Journal of Orthodontics vol 46 no 10 pp 721ndash7351960

[31] I Ceylan ldquoFarklı Iskelet yapılarında dik yon kranyo-fasiyalmorfoloji hyoid kemigin konumu ve birinci servikal verte-branın morfolojisinin incelenmesirdquo Turk Ortodonti Dernegivol 8 no 1 pp 20ndash29 1995

[32] A G Brodie ldquoAnatomy and physiology of head and neckmusculaturerdquoTheAmerican Journal of Orthodontics vol 36 no11 pp 831ndash844 1950

[33] E Atik and I Kocadereli ldquoCraniofacial morphology head pos-ture and hyoid bone positionrdquo Turkish Journal of Orthodonticsvol 24 no 3 pp 237ndash246 2011

[34] J A Ogden ldquoRadiology of postnatal skeletal development XIThe first cervical vertebrardquo Skeletal Radiology vol 12 no 1 pp12ndash20 1984

[35] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in class I and class III malocclusionsrdquo TheAmerican Journal of Orthodontics and Dentofacial Orthopedicsvol 101 no 4 pp 308ndash312 1992

[36] B Solow S Siersbaek-Nielsen and E Greve ldquoAirway adequacyhead posture and craniofacial morphologyrdquo American Journalof Orthodontics vol 86 no 3 pp 214ndash223 1984

[37] S Valenzuela R Miralles M J Ravera et al ldquoDoes headposture have a significant effect on the hyoid bone positionand sternocleidomastoid electromyographic activity in youngadultsrdquo Journal of Craniomandibular Practice vol 23 no 3 pp204ndash211 2005

[38] R Surucu S Aras and A Soytarhan ldquoCephalometric evalua-tion of the immediate changes in cervical structures after theapplication of the activatorrdquo Turkish Journal of Orthodonticsvol 3 no 2 pp 44ndash49 1990

[39] N EggenspergerW Smolka and T Iizuka ldquoLong-term changesof hyoid bone position and pharyngeal airway size followingmandibular setback by sagittal split ramus osteotomyrdquo Journalof Cranio-Maxillofacial Surgery vol 33 no 2 pp 111ndash117 2005

[40] G Marsan E Oztas N Cura S Vasfi Kuvat and U EmeklildquoChanges in head posture and hyoid bone position in Turkishclass III patients after mandibular setback surgeryrdquo Journal ofCranio-Maxillofacial Surgery vol 38 no 2 pp 113ndash121 2010

[41] A Gale P V J Kilpelainen andM T Laine-Alava ldquoHyoid boneposition after surgical mandibular advancementrdquo EuropeanJournal of Orthodontics vol 23 no 6 pp 695ndash701 2001

[42] B Solow and A Tallgren ldquoHead posture and craniofacialmorphologyrdquo The American Journal of Physical Anthropologyvol 44 no 3 pp 417ndash435 1976

[43] N B Haralabakis NM Toutountzakis and S C Yiagtzis ldquoThehyoid bone position in adult individuals with open bite andnormal occlusionrdquoEuropean Journal of Orthodontics vol 15 no4 pp 265ndash271 1993

[44] I Ceylan and H Oktay ldquoA study on the pharyngeal size in dif-ferent skeletal patternsrdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 108 no 1 pp 69ndash75 1995

[45] Y H Kim and J J Vietas ldquoAnteroposterior dysplasia indicatoran adjunct to cephalometric differential diagnosisrdquoThe Ameri-can Journal of Orthodontics vol 73 no 6 pp 619ndash633 1978

[46] W Hussels and R S Nanda ldquoAnalysis of factors affecting angleANBrdquo American Journal of Orthodontics vol 85 no 5 pp 411ndash423 1984

[47] H Oktay ldquoA comparison of ANBWits AF-BF and APDI mea-surementsrdquo American Journal of Orthodontics and DentofacialOrthopedics vol 104 no 2 pp 584ndash591 1991

[48] M M Ozbek and A Koklu ldquoNatural cervical inclination andcraniofacial structurerdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 104 no 6 pp 584ndash591 1993

[49] H Fjellvang and B Solow ldquoCraniocervical postural relationsand craniofacial morphology in 30 blind subjectsrdquo The Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol90 no 4 pp 327ndash334 1986

[50] A M Sahin Saglam and N E Uydas ldquoRelationship betweenhead posture and hyoid position in adult females and malesrdquoJournal of Cranio-Maxillofacial Surgery vol 34 no 2 pp 85ndash92 2006

[51] I Ceylan Degisik ANB Acılarında Dogal BasKonumu ve HyoidKemiginin Konumunun Incelenmesi Ataturk Universitesi SaglıkBilimleri Enstitusu Ortodonti Anabilim Dalı 1990

[52] B Dincer A Erdinc G Oncag and S Dogan ldquoThe investiga-tion of the hyoid bone position in class 1 class 2 division 1 andclass 3 malocclusionrdquo Turkish Journal of Orthodontics vol 13pp 108ndash115 2000

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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OrthopedicsAdvances in

Page 2: Research Article Cephalometric Investigation of First Cervical Vertebrae Morphology ...downloads.hindawi.com/journals/tswj/2014/159784.pdf ·  · 2015-11-22Research Article Cephalometric

2 The Scientific World Journal

via ligaments and muscles [17] The function of this structureis to maintain the positional balance of the respiratorypassage as well as respiratory sufficiency by anchoring thetongue It also has an important role in tongue function andin maintaining an upright head position and cranial balance[18] Because of its unique structure the position of thehyoid bone changes with head posture and body position andmoves during various oral functions in close association withtongue activity [19 20]Without the hyoid the position of thehead could not be maintained with the same degree of finecontrol [21]

In the literature it has been shown that changes inmandibular position are related to hyoid bone changesand that the hyoid position adapts to anterior-posteriorchanges in head posture [22ndash24] Furthermore studies onthe relationship between the hyoid and the facial skeletonand cervical column have indicated that the hyoid-cervicalrelationship is more stable than the relationship of the hyoidto the skull and mandible [22 25 26] Consequently studiesexamining different malocclusions can reveal the role of thehyoid bone in the dentofacial system and the response ofmandibular development to these malocclusions

Modern orthodontics studies dentomaxillofacial struc-tures including the head and neck When examining thesestructures and their relationships with one another theposition of hyoid bone with respect to other structuresbecomes important especially for preventing relapse afterorthodontic and orthognathic surgical treatment Accord-ingly the aim of this retrospective study was to examinehyoid bone position and C1 (atlas) morphology in males andfemales and analyze these parameterswith respect to differentsagittal skeletal patterns via cephalometry with the goal ofidentifying cephalometric norms

2 Methods

A total of 120 patients (60 males 60 females age average211 plusmn 29 years) who attended Dicle University Faculty ofDentistry Clinic ofOrthodontics forOrthodontic Treatmentparticipated in the present studyThe subject participation inthis study was retrospectively selected among patients thatindicate skeletal Cl I II and III relationshipThe radiographicdata included lateral cephalometric radiographs The criteriafor selection of patientsrsquo radiographs had to be of high qualityand sharpness and all radiographs had to be taken by thesame apparatus and same technician with patients in naturalhead posture Natural head posture was determined by usinga fluid level method as described by Showfety et al [27]

The patients were divided into three groups (Cl I IIand III) 119899 = 40 (119899 = 20 female 119899 = 20 male) sub-jects each according to a widely used indicator of skeletalanterior-posterior discrepancies known as the ANB angleThe ANB angle refers to the angle opened between theA-point the nasion and the B-point on a cephalographThis value was used by Steiner [28ndash30] as means to groupparticipants according to skeletal class Class I ANB = 2ndash4∘Class II ANB gt 4∘ and Class III ANB lt 2∘ In additioneach group was divided into subgroups according to sex

Table 1 Description of landmarks

Landmark Definition

Nasion (N) Most anterior point of the frontonasalsuture

Sella (S) Center of the sella turcica

Articulare (Ar)

Point of intersection between theposterior border of the mandibular ramusand the inferior border of the posteriorcranial base

Spina nasalisanterior (ANS)Spina nasalisposterior (PNS)

Pogonion (Pog) Most anterior point on the mandibularsymphysis

Gnathion (Gn) Most anterior-inferior point on themandibular symphysis

Menton (Me) Most inferior point on the mandibularsymphysis

Hyoid (Hy) Most superior-anterior point on the bodyof the hyoid bone

Hyoid1015840 (Hy1015840) Most superior-posterior point on thegrater horn of hyoid bone

CV4ip Most poster-inferior point on the corpusof the fourth cervical vertebra

CV2tg Most superior-posterior point on thecorpus of the fourth cervical vertebra

Table 2 Description of lines

Line Definition

CVT (the upper part ofthe cervical spine)

Line through CV2tg and CV4ipin the upper part of the cervicalspine

NSL (nasion-sella line) The nasion-sella line throughpoints N and S

NL (nasal line) The line through ANS and PNS

ML (mandibular line)The mandibular line tangentialto the lower border of themandible through Gn

Hy-Hy1015840 (hyoid line) The hyoid line passing throughHy and Hy1015840

(20 subjects each) All participants enrolled in this studyshowed normal vertical skeletal patterns (SNGoMe = 28ndash36∘) had not previously undergone orthodontic treatment ororthognathic surgery showed no visual hearing breathingor swallowing disorders and had no respiratory disturbanceor any other trauma affecting the craniofacial region

All cephalometric tracings were performed by the sameperson (SGA) using 003 mm matte acetate paper witha 3H pencil Eleven linear measurements were performedas described by Ceylan [31] Based on the landmarks andlines defined in Tables 1 and 2 respectively a total of 14angular and linear measurements were assessed as describedin Table 3 The cephalometric landmarks and measurementswere shown in Figures 1 and 2

The Scientific World Journal 3

Table 3 Description of linear measurements

Landmark Definition

Hy-NSL Linear distance from H along a perpendicularto NSL

Hy-NL Linear distance from H along a perpendicularto the NL

Hy-Hy1015840ML Linear distance from hyoid line to mandibularline

Hy-CVT Linear distance from H along a perpendicularto CVT

Hy-Pog The linear distance between H and pogonionHy-Me The linear distance between H and menton

119883

Distance between inferior border of theoccipital bone and dorsal arch of first cervicalvertebrae

119884Distance between most superior and inferiorpoints of first cervical vertebraersquos dorsal arch

119885

Distance between most inferior point of firstcervical vertebraersquos dorsal arch and mostsuperior point of second cervical vertebraersquos(axis) spinal process

Lum

Distance between anterior border of the firstcervical vertebraersquos dorsal arch and posteriorborder of the second cervical vertebraersquosodontoid process

a-pDistance between first cervical vertebraersquos mostfrontal point of tuberculum anterior and mostposterior point of dorsal arch

Two weeks after the first measurements 30 radiographswere selected at random and remeasured and a correlationanalysis was performed using data from the first and secondmeasurements Differences observed between the first andsecond measurements were not significant (119875 gt 005)

All statistical analyses were performed using the Statisti-cal Package for Social Sciences version 100 (SPSS ChicagoIllinois USA) Gender differences among groups were ana-lyzed using paired-sample t-tests Mean differences amonggroups were examined by analysis of variance (ANOVA) forrepeated measures with a post hoc least significant difference(LSD) test for multiple comparisonsThe level of significancefor all analyses was set at 119875 lt 005

3 Results

Intragroup (male versus female participants) and intergroupcomparisons of differences between different skeletal patternsare shown in Tables 4 5 and 6 Intragroup comparison ofClass I male and female participants revealed statisticallysignificant differences in the Hy-NSL (119875 lt 0001) Hy-PD(119875 lt 0001) Hy-CVT (119875 lt 0001) 119883 (119875 = 0004) 119884 (119875 =0012) Lum (119875 = 0013) and a-p (119875 = 0001) measurementsAlthough the hyoid bone was positioned more inferiorlyand anteriorly in males than in females with Class I skeletalpatterns the dimensional measurements for C1 revealed thatthis vertebra was larger and positioned lower in males Inthe intragroup comparison ofClass II participants significant

Top

CV2tg

CV4ip

Go

PNS

S N

AANS

MeGn

BPog

Ar

HyHy998400

Figure 1 Angular and linear measurements used

Top

CV2ap

Ar

Lum

X

Y

Z

Figure 2 Linear measurements on the first cervical vertebrae

differences were observed for Hy-NSL (119875 = 0006) Hy-NL(119875 = 0050) and Hy-CVT (119875 = 0001) The measurementsHy-NSL (119875 lt 0001) Hy-NL (119875 = 0003) Hy-CVT (119875 lt0001) Lum (119875 = 0027) and a-p (119875 = 029) alsoshowed statistically significant differences in the intragroupcomparison for Class III participants All measurements weregreater inmagnitude formale versus female participantsThehyoid was positioned more inferiorly and anteriorly in maleswith Class II and Class III skeletal patterns In addition C1was larger in the anterior-posterior direction in males versusfemales with Class III skeletal patterns

Intergroup comparison showed statistically differences inthe SNA ANB Hy-CVT 119883 and 119885 measurements in maleparticipants In addition SNA showed statistically significantdifferences between Class II and Class III participants (119875 =0006) and between Class I and Class III participants (119875 =0003) ANB also revealed statistically significant differencesamong all groups (119875 lt 0001) Hy-CVT showed statis-tically significant differences between Class I and Class IIparticipants (119875 = 0019) The 119883 and 119885 measurements weresignificantly different between Class I versus Class III (119875 =0010) and Class II versus Class III (119875 = 0004) participantsrespectively The hyoid was positioned more posteriorly inparticipants with Class II skeletal patterns compared to thosewith Class I skeletal patterns In addition the posterior part

4 The Scientific World Journal

Table4Intragroup

comparis

onof

malea

ndfemalep

artic

ipants

Measurements

ClassI

ClassII

ClassIII

Female(119899=20)

Male(119899=20)

(119875value)

Female(119899=20)

Male(119899=20)

(119875value)

Female(119899=20)

Male(119899=20)

(119875value)

Mean

SDMean

SDMean

SDMean

SDMean

SDMean

SDSN

A(∘ )

8080

446

8360

503

0268

NS

8330

539

8337

381

0858

NS

7900

485

7677

435

0434

NS

SNB(∘ )

7790

448

8040

485

0053

NS

7660

560

7643

335

0858

NS

8080

391

7888

416

0510

NS

ANB(∘ )

290

128

320

101

0240

NS

670

067

693

104

0776

NSminus18

0204

minus211

078

0127

NS

HyHy1015840MD(∘ )

770

537

540

291

0424

NS

840

389

1175

954

0624

NS

840

537

1177

993

0624

NS

Hy-NSL

(mm)

10370

427

12060

791

000

0lowastlowastlowast

10560

554

11887

1052

000

6lowastlowast

10600

522

11966

756

0001lowastlowast

HyNL(m

m)

5950

467

7110

667

0001lowastlowast

6350

667

7162

930

0050lowast

6210

508

7177

624

0003lowastlowast

Hy-CV

T(m

m)

4940

279

5930

266

000

0lowastlowastlowast

5020

278

5612

164

0001lowastlowast

4990

268

5866

327

000

0lowastlowastlowast

HyPo

g(mm)

5490

818

5110

360

0196

NS

5160

356

5025

647

096

4NS

5190

540

4977

591

0566

NS

HyMe(mm)

4910

724

4360

368

0063

NS

4440

394

4275

625

0562

NS

4520

431

4366

593

0623

NS

119883(m

m)

800

163

1170

262

000

4lowastlowast

860

195

937

287

0743

NS

910

213

822

263

0677

NS

119884(m

m)

830

125

1040

171

0012lowast

870

149

975

237

0470

NS

850

143

966

122

0077

NS

119885(m

m)

700

221

730

226

0908

NS

650

241

587

241

0369

NS

780

147

911

161

0086

NS

LUM

(mm)

2790

272

3120

229

0013lowast

284

222

2987

285

0227

NS

2900

309

3400

683

0027lowast

a-p(m

m)

4690

185

5190

246

0001lowastlowast

4850

201

5075

399

0192

NS

4740

241

4988

664

0029lowast

lowast

119875lt005lowastlowast

119875lt001lowastlowastlowast

119875lt0001NSno

nsignificantSD

stand

arddeviation

and119899num

bero

fpatients

The Scientific World Journal 5

Table 5 Intergroup comparison of mean differences among males with Class I II and III skeletal patterns

Measurements Class I (119899 = 20) Class II (119899 = 20) Class III (119899 = 20) ANOVA Multiple comparison LSD test (119875 value)Mean SD Mean SD Mean SD CI-CII CII-CIII CI-CIII

SNA (∘) 8360 503 8338 381 7678 435 lowastlowast 0917 0006 0003SNB (∘) 8040 485 7644 335 7889 416 NS 0060 0245 0445ANB (∘) 320 131 694 114 minus211 078 lowastlowastlowast 0000 0000 0000Hy Hy1015840 MD (∘) 540 291 1175 954 1178 993 NS 0104 0994 0092Hy NSL (mm) 12060 791 11888 1052 11967 756 NS 0678 0852 0816Hy NL (mm) 7110 667 7162 930 7178 624 NS 0883 0967 0844Hy-CVT (mm) 5930 266 5612 164 5967 227 lowast 0019 0060 0608Hy Pog (mm) 5110 360 5025 647 4978 591 NS 0741 0858 0596Hy Me (mm) 4360 368 4275 625 4367 593 NS 0739 0726 0978119883 (mm) 1170 262 938 287 822 263 lowast 0082 0389 0010119884 (mm) 1040 171 975 237 967 122 NS 0454 0925 0384119885 (mm) 730 226 588 241 911 161 lowast 0169 0004 0075LUM (mm) 3120 230 2988 285 3400 683 NS 0537 0069 0185a-p (mm) 5190 247 5075 399 4989 664 NS 0607 0707 0356lowast

119875 lt 005 lowastlowast119875 lt 001 lowastlowastlowast119875 lt 0001 NS statistically not significant SD standard deviation and 119899 number of patients

Table 6 Intergroup comparison of mean differences among females with Class I II and III skeletal patterns

Measurements Class I (119899 = 20) Class II (119899 = 20) Class III (119899 = 20) ANOVA Multiple comparison LSD test (119875 value)Mean SD Mean SD Mean SD CI-CII CII-CIII CI-CIII

SNA (∘) 8080 446 8330 539 7900 485 NS 0266 0061 0421SNB (∘) 7790 448 7660 56 8080 391 NS 0895 0072 0094ANB (∘) 290 128 670 067 minus180 104 lowastlowastlowast 0000 0000 0000Hy Hy1015840 MD (∘) 770 537 840 389 840 537 NS 0753 1000 0753Hy NSL (mm) 10370 427 10560 554 10600 522 NS 0407 0861 0317Hy NL (mm) 5950 467 6350 667 6210 508 NS 0118 0577 0304Hy-CVT (mm) 4940 279 5020 278 4990 268 NS 0522 0809 0688Hy Pog (mm) 5490 818 5160 356 5190 540 NS 0231 0912 0275Hy Me (mm) 4910 724 4440 395 4520 431 NS 0061 0742 0117119883 (mm) 800 163 860 195 910 213 NS 0490 0565 0211119884 (mm) 830 125 870 149 850 143 NS 0527 0751 0751119885 (mm) 700 221 65 241 78 147 NS 0594 0172 0396LUM (mm) 2790 272 284 222 2900 309 NS 0682 0624 0371a-p (mm) 4690 185 4850 201 4740 241 NS 0101 0253 0600lowastlowastlowast

119875 lt 0001 NS statistically not significant SD standard deviation and 119899 number of patients

of C1 was positioned more inferiorly among participantswith Class I versus Class III skeletal patterns C1 was alsocloser to C2 among participants of Class II versus ClassIII skeletal patterns In contrast the intergroup comparisonamong female participants revealed a significant difference inonly the ANB measurement among the groups

4 Discussion

The position of the hyoid bone is of great clinical interestbecause it plays an important role in maintaining the dimen-sions of the upper airway and an upright natural head posture

[26 32 33] The first cervical vertebra also known as theatlas represents the transition between the skull and the axialskeleton and it is reported that the dimensions of this vertebraaffect aspects of both the facial skeleton and the cervicalcolumn [34] Numerous previous studies have shown thatorthodontic treatments impacting mandibular position canalso alter the position of the hyoid given that it is attachedto the mandible via the geniohyoid anterior digastric andmylohyoid muscles [35ndash37]

Graber [18] evaluated the position of the hyoid in 30children (16 males and 14 females mean age of 6 years) afterorthopedic treatment for mandibular prognathism Graberobserved that the hyoid position had shifted posteriorly

6 The Scientific World Journal

and inferiorly at 3 years after treatment Surucu et al [38]examined 10 individuals with skeletal Class II division Imalocclusions and found that after the activator was appliedand the bite was opened the tongue shifted posteriorly andcaused constriction of the upper airway To compensate forthis constriction patients would need to alter their normalupright head posture by extending the headjawThe authorsreported that as a result of these changes the mandiblemoved into a more anterior position while the hyoid shiftedanteriorly depending on the degree of head extension It hasbeen reported that the hyoidmoves posteriorly and inferiorlyin mandibular setback surgeries [39 40] This subsequentlyresults in the base of the tongue shifting posteriorly andinferiorly resulting in constriction of the upper airway andforcing the patient to further extend the head positionto lengthen the upper airway Posterior movement of themandible can cause relaxation of the suprahyoidmusculaturewhich may instigate balance disorders in the head and neckmuscles and oropharyngeal complex It has been postulatedthat if this relaxation continues for an extended period it canalter the position of the hyoid as well as the length of thesuprahyoid muscle causing skeletal relapse [41]

Cephalometric radiography one of the most importanttools in orthodontics both clinically and in research permitsthe accurate evaluation of the dental skeletal and soft tissuerelationships of the craniofacial complex before the initiationof treatment and during growth [42ndash44]

In light of this information the aim of this study wasto document the position of the hyoid bone and cervicalatlas morphology on the cephalometric radiographs of par-ticipants with different sagittal skeletal patterns with the goalof identifying cephalometric norms To achieve this partic-ipants were classified according to horizontal discrepanciesobserved in the ANB angle a parameter that is widely usedin the evaluation of skeletal anterior-posterior relationships[45ndash47] Previous studies have shown that natural headposture is related to respiratory [48] and visual function[49] Therefore to determine natural head posture in aprecise manner only individuals without visual hearing orrespiratory disturbances were included in this study

Our results from the intragroup comparison of Class Iand Class II participants revealed that several measurementswere significantly larger in males than in females Theseincluded Hy-NSL (119875 lt 0001) Hy-PD (119875 = 0001) andHy-CVT (119875 lt 0001) In addition the hyoid was positionedmore anteriorly and inferiorly in males than in femalesSahin Saglam and Uydas [50] investigated variation in hyoidposition and head posture between genders (38 females and38 males) using lateral cephalometric films obtained using anatural head position All participants had a Class I skeletalpattern and ideal dental occlusion The authors found thatnatural head position did not differ between genders but thehyoid bone was positioned more superiorly and posteriorlyin females compared to males Ceylan [51] examined 90adolescents including 45 boys and 45 girls aged 13ndash15 yearsand analyzed the relationship of the ANB angle and naturalhead position to the position of the hyoid bone Naturalhead position was not significantly affected by gender butthe hyoid bone was positioned significantly more superiorly

and posteriorly in females than in males These results areconsistent with the data reported here

In the intragroup comparison of Class I participantssignificant differences were observed with respect to the 119883119884 Lum and a-p parameters all of which were smaller infemales The data also revealed a greater superior-posteriorarea of C1 shorter distance between C1 and C2 shorteranterior-posterior dimensions and shorter distance betweenthe anterior border of the C1 dorsal arch and the posteriorborder of the C2 odontoid process also in females Theseresults suggest that the male body is more developed than thefemale body

In the intragroup comparison of Class III participantsit was found that the hyoid bone was positioned moreanteriorly and inferiorly in males than in females Cervicaland craniocervical posture may be one factor explaining thesignificant differences observed between males and femaleswho have Class III malocclusions [24] Females who haveClass III malocclusions show amuchmore ldquonormalrdquo positionof the hyoid bone as compared to males with Class IIImalocclusions This may be due to heightened aestheticawareness of a prognathic mandible in girls which leadsthem to assume quite early in life a modified head postureallowing them to minimize the appearance of a prominentchin

Intergroup comparisons of differences between gendersshowed statistically significant differences in ANB measure-ments in all groups These results are unsurprising giventhat participants with normal vertical patterns and differentANB values were included in this study In the intergroupcomparison of males the Hy-CVT distance was found to begreater in Class I than in Class II participants This indicatespronounced anterior positioning of the hyoid bone in Class Imales On the other hand Ceylan [31] evaluated the hyoidbone position in different skeletal patterns of adolescentsaged 13ndash15 years and reported that the hyoid bone waspositionedmore anteriorlywith an increase in theANBangleThis is in direct contrast to our study whichmay be the resultof examining different age groups (adolescents versus youngadults) and the inclusion of participants with normal verticalskeletal patterns in our work Dincer et al [52] investigatedthe position of the hyoid bone with respect to its relationshipwith the dentofacial system in 45 participants with ClassI Class II division I and Class III malocclusions It wasascertained that the hyoid was positioned more posteriorlyamong participants with a Class II division I skeletal patterncompared to a Class I pattern and more anteriorly amongparticipants with a Class III skeletal pattern compared toa Class I pattern In addition the greater 119883 values amongClass I versus Class III participants indicate an overall lowerposition of C1 in the Class I group Class III participants hadhigher 119885 values compared to the Class II group accordinglythe distance between the posterior part of C1 andC2 is greaterin Class III versus Class II participants

Regarding skeletal patterns in female participants no dif-ference was observed for parameters relating to the hyoid orC1 indicating nomorphological difference in these structuresamong females Consistent with our findings Adamidis andSpyropoulos [24] found no statistically significant differences

The Scientific World Journal 7

in the position or orientation of the hyoid among femalesexhibiting Class I malocclusions versus those with Class IIImalocclusions

5 Conclusions

This study revealed that the hyoid bone is positioned moreinferiorly and anteriorly and is more prominent in malesthan in females regardless of variation in the axial skeletonC1 was also larger along the anterior-posterior axis in malesexhibiting a Class I skeletal pattern compared to females inthe same class However no significant difference in hyoidposition or C1 morphology was observed in relation to theANB in females In the sagittal plane the hyoid bone wassimilar in males with a Class I or Class III skeletal patternbut was positioned more posteriorly based on mandibularbone development in males with Class I skeletal patterns Inaddition the vertical position of C1 varied depending on thesagittal skeletal pattern among male participants

It is especially important among males that the hyoidbone remains in the same position after orthodontic andorthognathic treatment so that the balance of the soft tissuesis not altered thus reducing the chance of relapse Theresults of this study are therefore highly useful for clinicianswho must assess the stability of these structures in patientswho are candidates for orthognathic or orthopedic surgerywhich may help to prevent the obstruction of the upperairway In addition this study helps to identify cephalometricnorms that exist amongmales and females who have differentskeletal sagittal anomalies

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] A G Brodie ldquoEmerging concepts of facial growthrdquo AngleOrthodontist vol 41 no 2 pp 103ndash118 1971

[2] D K Bailey ldquoThenormal cervical spine in infants and childrenrdquoRadiology vol 59 no 5 pp 712ndash719 1952

[3] S W Gray C B Romanie and J E Skandalakis ldquoCongenitalfusion of the cervical vertebraerdquo Surgery Gynecology amp Obstet-rics vol 118 pp 373ndash385 1964

[4] J Huggare ldquoAssociation between morphology of the firstcervical vertebra head posture and craniofacial structuresrdquoEuropean Journal of Orthodontics vol 13 no 6 pp 435ndash4401991

[5] M Sandikcioglu S Skov and B Solow ldquoAtlas morphologyin relation to craniofacial morphology and head posturerdquoEuropean Journal ofOrthodontics vol 16 no 2 pp 96ndash103 1994

[6] E Hellsing J McWilliam T Reigo and E Spangfort ldquoTherelationship between craniofacial morphology head postureand spinal curvature in 8 11 and 15-year-old childrenrdquo EuropeanJournal of Orthodontics vol 9 no 4 pp 254ndash264 1987

[7] J Huggare ldquoA cross-sectional study of head posture andcraniofacial growth in children from the north of Finlandrdquo

Proceedings of the Finnish Dental Society vol 83 no 1 pp 5ndash15 1987

[8] J Huggare and P Houghton ldquoAssociations between atlantoaxialand craniomandibular anatomyrdquo Growth Development andAging vol 60 no 1 pp 21ndash30 1996

[9] A Wenzel E Hojensgaard and J M Henriksen ldquoCraniofacialmorphology and head posture in children with asthma andperennial rhinitisrdquo European Journal of Orthodontics vol 7 no2 pp 83ndash92 1985

[10] L Sonnesen M Bakke and B Solow ldquoTemporomandibulardisorders in relation to craniofacial dimensions head postureand bite force in children selected for orthodontic treatmentrdquoEuropean Journal of Orthodontics vol 23 no 2 pp 179ndash1922001

[11] C M Visscher W De Boer F Lobbezoo L L M H HabetsandMNaeije ldquoIs there a relationship between head posture andcraniomandibular painrdquo Journal of Oral Rehabilitation vol 29no 11 pp 1030ndash1036 2002

[12] H Treuenfels ldquoDie Relation von Atlasposition prognather undprogener Kieferanomalierdquo Fortschritte der Kieferorthopadie vol43 no 1 p 82 1982

[13] U Gustavsson G Hansson A Holmqvist and M LundbergldquoHyoid bone position in relation to head posturerdquo SwedishDental Journal vol 65 no 8 pp 423ndash430 1972

[14] J W Pim Valk A J J Zonnenberg C J van Maanen and OG T van Wonderen ldquoThe biomechanical effects of a sagittalsplit ramus osteotomy on the relationship of the mandible thehyoid bone and the cervical spinerdquo The American Journal ofOrthodontics and Dentofacial Orthopedics vol 102 no 2 pp99ndash108 1992

[15] A Tallgren and B Solow ldquoHyoid bone position facial mor-phology and head posture in adultsrdquo European Journal ofOrthodontics vol 9 no 1 pp 1ndash8 1987

[16] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo AmericanJournal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[17] G J Romanes Cunninghamrsquos Manual of Practical Anatomy vol3 Oxford University Press New York NY USA 14th edition1983

[18] L W Graber ldquoHyoid changes following orthopedic treatmentof mandibular prognathismrdquo Angle Orthodontist vol 48 no 1pp 33ndash38 1978

[19] KMHiiemae SMHayenga andA Reese ldquoPatterns of tongueand jawmovement in a cinefluorographic study of feeding in themacaquerdquo Archives of Oral Biology vol 40 no 3 pp 229ndash2461995

[20] J Spiro J K Rendell and T Gay ldquoActivation and coordinationpatterns of the suprahyoid muscles during swallowingrdquo Laryn-goscope vol 104 no 11 I pp 1376ndash1382 1994

[21] H Tsai ldquoThe positional changes of hyoid bone in childrenrdquoTheJournal of Clinical Pediatric Dentistry vol 27 no 1 pp 29ndash342002

[22] B Fromm and M Lundberg ldquoPostural behaviour of the hyoidbone in normal occlusion and before and after surgical correc-tion of mandibular protrusionrdquo Swedish Dental Journal vol 63no 6 pp 425ndash433 1970

[23] H Opdebeeck W H Bell J Eisenfeld and D MishelevichldquoComparative study between the SFS and LFS rotation as apossible morphogenic mechanismrdquo The American Journal ofOrthodontics vol 74 no 5 pp 509ndash521 1978

8 The Scientific World Journal

[24] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in Class I and Class III malocclusionsrdquo Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol101 no 4 pp 308ndash312 1992

[25] S Carlsoo and G Leijon ldquoA radiographic study of the positionof the hyo-Iaryngeal complex in relation to the skull and thecervical column in manrdquo Transactions Royal Schools DentistryStockholm and Umeft vol 5 pp 13ndash34 1960

[26] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo TheAmerican Journal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[27] K J Showfety P S Vig and S Matteson ldquoA simple method fortaking natural-head-position cephalogramsrdquo American Journalof Orthodontics vol 83 no 6 pp 495ndash500 1983

[28] C C Steiner ldquoCephalometrics for you and merdquo The AmericanJournal of Orthodontics vol 39 no 10 pp 729ndash755 1953

[29] C C Steiner ldquoCephalometrics in clinical practicerdquo The AngleOrthodontist vol 29 no 1 pp 8ndash29 1959

[30] C C Steiner ldquoThe use of cephalometrics as an aid to planningand assessing orthodontic treatment Report of a caserdquo TheAmerican Journal of Orthodontics vol 46 no 10 pp 721ndash7351960

[31] I Ceylan ldquoFarklı Iskelet yapılarında dik yon kranyo-fasiyalmorfoloji hyoid kemigin konumu ve birinci servikal verte-branın morfolojisinin incelenmesirdquo Turk Ortodonti Dernegivol 8 no 1 pp 20ndash29 1995

[32] A G Brodie ldquoAnatomy and physiology of head and neckmusculaturerdquoTheAmerican Journal of Orthodontics vol 36 no11 pp 831ndash844 1950

[33] E Atik and I Kocadereli ldquoCraniofacial morphology head pos-ture and hyoid bone positionrdquo Turkish Journal of Orthodonticsvol 24 no 3 pp 237ndash246 2011

[34] J A Ogden ldquoRadiology of postnatal skeletal development XIThe first cervical vertebrardquo Skeletal Radiology vol 12 no 1 pp12ndash20 1984

[35] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in class I and class III malocclusionsrdquo TheAmerican Journal of Orthodontics and Dentofacial Orthopedicsvol 101 no 4 pp 308ndash312 1992

[36] B Solow S Siersbaek-Nielsen and E Greve ldquoAirway adequacyhead posture and craniofacial morphologyrdquo American Journalof Orthodontics vol 86 no 3 pp 214ndash223 1984

[37] S Valenzuela R Miralles M J Ravera et al ldquoDoes headposture have a significant effect on the hyoid bone positionand sternocleidomastoid electromyographic activity in youngadultsrdquo Journal of Craniomandibular Practice vol 23 no 3 pp204ndash211 2005

[38] R Surucu S Aras and A Soytarhan ldquoCephalometric evalua-tion of the immediate changes in cervical structures after theapplication of the activatorrdquo Turkish Journal of Orthodonticsvol 3 no 2 pp 44ndash49 1990

[39] N EggenspergerW Smolka and T Iizuka ldquoLong-term changesof hyoid bone position and pharyngeal airway size followingmandibular setback by sagittal split ramus osteotomyrdquo Journalof Cranio-Maxillofacial Surgery vol 33 no 2 pp 111ndash117 2005

[40] G Marsan E Oztas N Cura S Vasfi Kuvat and U EmeklildquoChanges in head posture and hyoid bone position in Turkishclass III patients after mandibular setback surgeryrdquo Journal ofCranio-Maxillofacial Surgery vol 38 no 2 pp 113ndash121 2010

[41] A Gale P V J Kilpelainen andM T Laine-Alava ldquoHyoid boneposition after surgical mandibular advancementrdquo EuropeanJournal of Orthodontics vol 23 no 6 pp 695ndash701 2001

[42] B Solow and A Tallgren ldquoHead posture and craniofacialmorphologyrdquo The American Journal of Physical Anthropologyvol 44 no 3 pp 417ndash435 1976

[43] N B Haralabakis NM Toutountzakis and S C Yiagtzis ldquoThehyoid bone position in adult individuals with open bite andnormal occlusionrdquoEuropean Journal of Orthodontics vol 15 no4 pp 265ndash271 1993

[44] I Ceylan and H Oktay ldquoA study on the pharyngeal size in dif-ferent skeletal patternsrdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 108 no 1 pp 69ndash75 1995

[45] Y H Kim and J J Vietas ldquoAnteroposterior dysplasia indicatoran adjunct to cephalometric differential diagnosisrdquoThe Ameri-can Journal of Orthodontics vol 73 no 6 pp 619ndash633 1978

[46] W Hussels and R S Nanda ldquoAnalysis of factors affecting angleANBrdquo American Journal of Orthodontics vol 85 no 5 pp 411ndash423 1984

[47] H Oktay ldquoA comparison of ANBWits AF-BF and APDI mea-surementsrdquo American Journal of Orthodontics and DentofacialOrthopedics vol 104 no 2 pp 584ndash591 1991

[48] M M Ozbek and A Koklu ldquoNatural cervical inclination andcraniofacial structurerdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 104 no 6 pp 584ndash591 1993

[49] H Fjellvang and B Solow ldquoCraniocervical postural relationsand craniofacial morphology in 30 blind subjectsrdquo The Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol90 no 4 pp 327ndash334 1986

[50] A M Sahin Saglam and N E Uydas ldquoRelationship betweenhead posture and hyoid position in adult females and malesrdquoJournal of Cranio-Maxillofacial Surgery vol 34 no 2 pp 85ndash92 2006

[51] I Ceylan Degisik ANB Acılarında Dogal BasKonumu ve HyoidKemiginin Konumunun Incelenmesi Ataturk Universitesi SaglıkBilimleri Enstitusu Ortodonti Anabilim Dalı 1990

[52] B Dincer A Erdinc G Oncag and S Dogan ldquoThe investiga-tion of the hyoid bone position in class 1 class 2 division 1 andclass 3 malocclusionrdquo Turkish Journal of Orthodontics vol 13pp 108ndash115 2000

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Case Reports in Dentistry

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Oral ImplantsJournal of

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Anesthesiology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Radiology Research and Practice

Environmental and Public Health

Journal of

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The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

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Oral DiseasesJournal of

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Preventive MedicineAdvances in

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OrthopedicsAdvances in

Page 3: Research Article Cephalometric Investigation of First Cervical Vertebrae Morphology ...downloads.hindawi.com/journals/tswj/2014/159784.pdf ·  · 2015-11-22Research Article Cephalometric

The Scientific World Journal 3

Table 3 Description of linear measurements

Landmark Definition

Hy-NSL Linear distance from H along a perpendicularto NSL

Hy-NL Linear distance from H along a perpendicularto the NL

Hy-Hy1015840ML Linear distance from hyoid line to mandibularline

Hy-CVT Linear distance from H along a perpendicularto CVT

Hy-Pog The linear distance between H and pogonionHy-Me The linear distance between H and menton

119883

Distance between inferior border of theoccipital bone and dorsal arch of first cervicalvertebrae

119884Distance between most superior and inferiorpoints of first cervical vertebraersquos dorsal arch

119885

Distance between most inferior point of firstcervical vertebraersquos dorsal arch and mostsuperior point of second cervical vertebraersquos(axis) spinal process

Lum

Distance between anterior border of the firstcervical vertebraersquos dorsal arch and posteriorborder of the second cervical vertebraersquosodontoid process

a-pDistance between first cervical vertebraersquos mostfrontal point of tuberculum anterior and mostposterior point of dorsal arch

Two weeks after the first measurements 30 radiographswere selected at random and remeasured and a correlationanalysis was performed using data from the first and secondmeasurements Differences observed between the first andsecond measurements were not significant (119875 gt 005)

All statistical analyses were performed using the Statisti-cal Package for Social Sciences version 100 (SPSS ChicagoIllinois USA) Gender differences among groups were ana-lyzed using paired-sample t-tests Mean differences amonggroups were examined by analysis of variance (ANOVA) forrepeated measures with a post hoc least significant difference(LSD) test for multiple comparisonsThe level of significancefor all analyses was set at 119875 lt 005

3 Results

Intragroup (male versus female participants) and intergroupcomparisons of differences between different skeletal patternsare shown in Tables 4 5 and 6 Intragroup comparison ofClass I male and female participants revealed statisticallysignificant differences in the Hy-NSL (119875 lt 0001) Hy-PD(119875 lt 0001) Hy-CVT (119875 lt 0001) 119883 (119875 = 0004) 119884 (119875 =0012) Lum (119875 = 0013) and a-p (119875 = 0001) measurementsAlthough the hyoid bone was positioned more inferiorlyand anteriorly in males than in females with Class I skeletalpatterns the dimensional measurements for C1 revealed thatthis vertebra was larger and positioned lower in males Inthe intragroup comparison ofClass II participants significant

Top

CV2tg

CV4ip

Go

PNS

S N

AANS

MeGn

BPog

Ar

HyHy998400

Figure 1 Angular and linear measurements used

Top

CV2ap

Ar

Lum

X

Y

Z

Figure 2 Linear measurements on the first cervical vertebrae

differences were observed for Hy-NSL (119875 = 0006) Hy-NL(119875 = 0050) and Hy-CVT (119875 = 0001) The measurementsHy-NSL (119875 lt 0001) Hy-NL (119875 = 0003) Hy-CVT (119875 lt0001) Lum (119875 = 0027) and a-p (119875 = 029) alsoshowed statistically significant differences in the intragroupcomparison for Class III participants All measurements weregreater inmagnitude formale versus female participantsThehyoid was positioned more inferiorly and anteriorly in maleswith Class II and Class III skeletal patterns In addition C1was larger in the anterior-posterior direction in males versusfemales with Class III skeletal patterns

Intergroup comparison showed statistically differences inthe SNA ANB Hy-CVT 119883 and 119885 measurements in maleparticipants In addition SNA showed statistically significantdifferences between Class II and Class III participants (119875 =0006) and between Class I and Class III participants (119875 =0003) ANB also revealed statistically significant differencesamong all groups (119875 lt 0001) Hy-CVT showed statis-tically significant differences between Class I and Class IIparticipants (119875 = 0019) The 119883 and 119885 measurements weresignificantly different between Class I versus Class III (119875 =0010) and Class II versus Class III (119875 = 0004) participantsrespectively The hyoid was positioned more posteriorly inparticipants with Class II skeletal patterns compared to thosewith Class I skeletal patterns In addition the posterior part

4 The Scientific World Journal

Table4Intragroup

comparis

onof

malea

ndfemalep

artic

ipants

Measurements

ClassI

ClassII

ClassIII

Female(119899=20)

Male(119899=20)

(119875value)

Female(119899=20)

Male(119899=20)

(119875value)

Female(119899=20)

Male(119899=20)

(119875value)

Mean

SDMean

SDMean

SDMean

SDMean

SDMean

SDSN

A(∘ )

8080

446

8360

503

0268

NS

8330

539

8337

381

0858

NS

7900

485

7677

435

0434

NS

SNB(∘ )

7790

448

8040

485

0053

NS

7660

560

7643

335

0858

NS

8080

391

7888

416

0510

NS

ANB(∘ )

290

128

320

101

0240

NS

670

067

693

104

0776

NSminus18

0204

minus211

078

0127

NS

HyHy1015840MD(∘ )

770

537

540

291

0424

NS

840

389

1175

954

0624

NS

840

537

1177

993

0624

NS

Hy-NSL

(mm)

10370

427

12060

791

000

0lowastlowastlowast

10560

554

11887

1052

000

6lowastlowast

10600

522

11966

756

0001lowastlowast

HyNL(m

m)

5950

467

7110

667

0001lowastlowast

6350

667

7162

930

0050lowast

6210

508

7177

624

0003lowastlowast

Hy-CV

T(m

m)

4940

279

5930

266

000

0lowastlowastlowast

5020

278

5612

164

0001lowastlowast

4990

268

5866

327

000

0lowastlowastlowast

HyPo

g(mm)

5490

818

5110

360

0196

NS

5160

356

5025

647

096

4NS

5190

540

4977

591

0566

NS

HyMe(mm)

4910

724

4360

368

0063

NS

4440

394

4275

625

0562

NS

4520

431

4366

593

0623

NS

119883(m

m)

800

163

1170

262

000

4lowastlowast

860

195

937

287

0743

NS

910

213

822

263

0677

NS

119884(m

m)

830

125

1040

171

0012lowast

870

149

975

237

0470

NS

850

143

966

122

0077

NS

119885(m

m)

700

221

730

226

0908

NS

650

241

587

241

0369

NS

780

147

911

161

0086

NS

LUM

(mm)

2790

272

3120

229

0013lowast

284

222

2987

285

0227

NS

2900

309

3400

683

0027lowast

a-p(m

m)

4690

185

5190

246

0001lowastlowast

4850

201

5075

399

0192

NS

4740

241

4988

664

0029lowast

lowast

119875lt005lowastlowast

119875lt001lowastlowastlowast

119875lt0001NSno

nsignificantSD

stand

arddeviation

and119899num

bero

fpatients

The Scientific World Journal 5

Table 5 Intergroup comparison of mean differences among males with Class I II and III skeletal patterns

Measurements Class I (119899 = 20) Class II (119899 = 20) Class III (119899 = 20) ANOVA Multiple comparison LSD test (119875 value)Mean SD Mean SD Mean SD CI-CII CII-CIII CI-CIII

SNA (∘) 8360 503 8338 381 7678 435 lowastlowast 0917 0006 0003SNB (∘) 8040 485 7644 335 7889 416 NS 0060 0245 0445ANB (∘) 320 131 694 114 minus211 078 lowastlowastlowast 0000 0000 0000Hy Hy1015840 MD (∘) 540 291 1175 954 1178 993 NS 0104 0994 0092Hy NSL (mm) 12060 791 11888 1052 11967 756 NS 0678 0852 0816Hy NL (mm) 7110 667 7162 930 7178 624 NS 0883 0967 0844Hy-CVT (mm) 5930 266 5612 164 5967 227 lowast 0019 0060 0608Hy Pog (mm) 5110 360 5025 647 4978 591 NS 0741 0858 0596Hy Me (mm) 4360 368 4275 625 4367 593 NS 0739 0726 0978119883 (mm) 1170 262 938 287 822 263 lowast 0082 0389 0010119884 (mm) 1040 171 975 237 967 122 NS 0454 0925 0384119885 (mm) 730 226 588 241 911 161 lowast 0169 0004 0075LUM (mm) 3120 230 2988 285 3400 683 NS 0537 0069 0185a-p (mm) 5190 247 5075 399 4989 664 NS 0607 0707 0356lowast

119875 lt 005 lowastlowast119875 lt 001 lowastlowastlowast119875 lt 0001 NS statistically not significant SD standard deviation and 119899 number of patients

Table 6 Intergroup comparison of mean differences among females with Class I II and III skeletal patterns

Measurements Class I (119899 = 20) Class II (119899 = 20) Class III (119899 = 20) ANOVA Multiple comparison LSD test (119875 value)Mean SD Mean SD Mean SD CI-CII CII-CIII CI-CIII

SNA (∘) 8080 446 8330 539 7900 485 NS 0266 0061 0421SNB (∘) 7790 448 7660 56 8080 391 NS 0895 0072 0094ANB (∘) 290 128 670 067 minus180 104 lowastlowastlowast 0000 0000 0000Hy Hy1015840 MD (∘) 770 537 840 389 840 537 NS 0753 1000 0753Hy NSL (mm) 10370 427 10560 554 10600 522 NS 0407 0861 0317Hy NL (mm) 5950 467 6350 667 6210 508 NS 0118 0577 0304Hy-CVT (mm) 4940 279 5020 278 4990 268 NS 0522 0809 0688Hy Pog (mm) 5490 818 5160 356 5190 540 NS 0231 0912 0275Hy Me (mm) 4910 724 4440 395 4520 431 NS 0061 0742 0117119883 (mm) 800 163 860 195 910 213 NS 0490 0565 0211119884 (mm) 830 125 870 149 850 143 NS 0527 0751 0751119885 (mm) 700 221 65 241 78 147 NS 0594 0172 0396LUM (mm) 2790 272 284 222 2900 309 NS 0682 0624 0371a-p (mm) 4690 185 4850 201 4740 241 NS 0101 0253 0600lowastlowastlowast

119875 lt 0001 NS statistically not significant SD standard deviation and 119899 number of patients

of C1 was positioned more inferiorly among participantswith Class I versus Class III skeletal patterns C1 was alsocloser to C2 among participants of Class II versus ClassIII skeletal patterns In contrast the intergroup comparisonamong female participants revealed a significant difference inonly the ANB measurement among the groups

4 Discussion

The position of the hyoid bone is of great clinical interestbecause it plays an important role in maintaining the dimen-sions of the upper airway and an upright natural head posture

[26 32 33] The first cervical vertebra also known as theatlas represents the transition between the skull and the axialskeleton and it is reported that the dimensions of this vertebraaffect aspects of both the facial skeleton and the cervicalcolumn [34] Numerous previous studies have shown thatorthodontic treatments impacting mandibular position canalso alter the position of the hyoid given that it is attachedto the mandible via the geniohyoid anterior digastric andmylohyoid muscles [35ndash37]

Graber [18] evaluated the position of the hyoid in 30children (16 males and 14 females mean age of 6 years) afterorthopedic treatment for mandibular prognathism Graberobserved that the hyoid position had shifted posteriorly

6 The Scientific World Journal

and inferiorly at 3 years after treatment Surucu et al [38]examined 10 individuals with skeletal Class II division Imalocclusions and found that after the activator was appliedand the bite was opened the tongue shifted posteriorly andcaused constriction of the upper airway To compensate forthis constriction patients would need to alter their normalupright head posture by extending the headjawThe authorsreported that as a result of these changes the mandiblemoved into a more anterior position while the hyoid shiftedanteriorly depending on the degree of head extension It hasbeen reported that the hyoidmoves posteriorly and inferiorlyin mandibular setback surgeries [39 40] This subsequentlyresults in the base of the tongue shifting posteriorly andinferiorly resulting in constriction of the upper airway andforcing the patient to further extend the head positionto lengthen the upper airway Posterior movement of themandible can cause relaxation of the suprahyoidmusculaturewhich may instigate balance disorders in the head and neckmuscles and oropharyngeal complex It has been postulatedthat if this relaxation continues for an extended period it canalter the position of the hyoid as well as the length of thesuprahyoid muscle causing skeletal relapse [41]

Cephalometric radiography one of the most importanttools in orthodontics both clinically and in research permitsthe accurate evaluation of the dental skeletal and soft tissuerelationships of the craniofacial complex before the initiationof treatment and during growth [42ndash44]

In light of this information the aim of this study wasto document the position of the hyoid bone and cervicalatlas morphology on the cephalometric radiographs of par-ticipants with different sagittal skeletal patterns with the goalof identifying cephalometric norms To achieve this partic-ipants were classified according to horizontal discrepanciesobserved in the ANB angle a parameter that is widely usedin the evaluation of skeletal anterior-posterior relationships[45ndash47] Previous studies have shown that natural headposture is related to respiratory [48] and visual function[49] Therefore to determine natural head posture in aprecise manner only individuals without visual hearing orrespiratory disturbances were included in this study

Our results from the intragroup comparison of Class Iand Class II participants revealed that several measurementswere significantly larger in males than in females Theseincluded Hy-NSL (119875 lt 0001) Hy-PD (119875 = 0001) andHy-CVT (119875 lt 0001) In addition the hyoid was positionedmore anteriorly and inferiorly in males than in femalesSahin Saglam and Uydas [50] investigated variation in hyoidposition and head posture between genders (38 females and38 males) using lateral cephalometric films obtained using anatural head position All participants had a Class I skeletalpattern and ideal dental occlusion The authors found thatnatural head position did not differ between genders but thehyoid bone was positioned more superiorly and posteriorlyin females compared to males Ceylan [51] examined 90adolescents including 45 boys and 45 girls aged 13ndash15 yearsand analyzed the relationship of the ANB angle and naturalhead position to the position of the hyoid bone Naturalhead position was not significantly affected by gender butthe hyoid bone was positioned significantly more superiorly

and posteriorly in females than in males These results areconsistent with the data reported here

In the intragroup comparison of Class I participantssignificant differences were observed with respect to the 119883119884 Lum and a-p parameters all of which were smaller infemales The data also revealed a greater superior-posteriorarea of C1 shorter distance between C1 and C2 shorteranterior-posterior dimensions and shorter distance betweenthe anterior border of the C1 dorsal arch and the posteriorborder of the C2 odontoid process also in females Theseresults suggest that the male body is more developed than thefemale body

In the intragroup comparison of Class III participantsit was found that the hyoid bone was positioned moreanteriorly and inferiorly in males than in females Cervicaland craniocervical posture may be one factor explaining thesignificant differences observed between males and femaleswho have Class III malocclusions [24] Females who haveClass III malocclusions show amuchmore ldquonormalrdquo positionof the hyoid bone as compared to males with Class IIImalocclusions This may be due to heightened aestheticawareness of a prognathic mandible in girls which leadsthem to assume quite early in life a modified head postureallowing them to minimize the appearance of a prominentchin

Intergroup comparisons of differences between gendersshowed statistically significant differences in ANB measure-ments in all groups These results are unsurprising giventhat participants with normal vertical patterns and differentANB values were included in this study In the intergroupcomparison of males the Hy-CVT distance was found to begreater in Class I than in Class II participants This indicatespronounced anterior positioning of the hyoid bone in Class Imales On the other hand Ceylan [31] evaluated the hyoidbone position in different skeletal patterns of adolescentsaged 13ndash15 years and reported that the hyoid bone waspositionedmore anteriorlywith an increase in theANBangleThis is in direct contrast to our study whichmay be the resultof examining different age groups (adolescents versus youngadults) and the inclusion of participants with normal verticalskeletal patterns in our work Dincer et al [52] investigatedthe position of the hyoid bone with respect to its relationshipwith the dentofacial system in 45 participants with ClassI Class II division I and Class III malocclusions It wasascertained that the hyoid was positioned more posteriorlyamong participants with a Class II division I skeletal patterncompared to a Class I pattern and more anteriorly amongparticipants with a Class III skeletal pattern compared toa Class I pattern In addition the greater 119883 values amongClass I versus Class III participants indicate an overall lowerposition of C1 in the Class I group Class III participants hadhigher 119885 values compared to the Class II group accordinglythe distance between the posterior part of C1 andC2 is greaterin Class III versus Class II participants

Regarding skeletal patterns in female participants no dif-ference was observed for parameters relating to the hyoid orC1 indicating nomorphological difference in these structuresamong females Consistent with our findings Adamidis andSpyropoulos [24] found no statistically significant differences

The Scientific World Journal 7

in the position or orientation of the hyoid among femalesexhibiting Class I malocclusions versus those with Class IIImalocclusions

5 Conclusions

This study revealed that the hyoid bone is positioned moreinferiorly and anteriorly and is more prominent in malesthan in females regardless of variation in the axial skeletonC1 was also larger along the anterior-posterior axis in malesexhibiting a Class I skeletal pattern compared to females inthe same class However no significant difference in hyoidposition or C1 morphology was observed in relation to theANB in females In the sagittal plane the hyoid bone wassimilar in males with a Class I or Class III skeletal patternbut was positioned more posteriorly based on mandibularbone development in males with Class I skeletal patterns Inaddition the vertical position of C1 varied depending on thesagittal skeletal pattern among male participants

It is especially important among males that the hyoidbone remains in the same position after orthodontic andorthognathic treatment so that the balance of the soft tissuesis not altered thus reducing the chance of relapse Theresults of this study are therefore highly useful for clinicianswho must assess the stability of these structures in patientswho are candidates for orthognathic or orthopedic surgerywhich may help to prevent the obstruction of the upperairway In addition this study helps to identify cephalometricnorms that exist amongmales and females who have differentskeletal sagittal anomalies

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] A G Brodie ldquoEmerging concepts of facial growthrdquo AngleOrthodontist vol 41 no 2 pp 103ndash118 1971

[2] D K Bailey ldquoThenormal cervical spine in infants and childrenrdquoRadiology vol 59 no 5 pp 712ndash719 1952

[3] S W Gray C B Romanie and J E Skandalakis ldquoCongenitalfusion of the cervical vertebraerdquo Surgery Gynecology amp Obstet-rics vol 118 pp 373ndash385 1964

[4] J Huggare ldquoAssociation between morphology of the firstcervical vertebra head posture and craniofacial structuresrdquoEuropean Journal of Orthodontics vol 13 no 6 pp 435ndash4401991

[5] M Sandikcioglu S Skov and B Solow ldquoAtlas morphologyin relation to craniofacial morphology and head posturerdquoEuropean Journal ofOrthodontics vol 16 no 2 pp 96ndash103 1994

[6] E Hellsing J McWilliam T Reigo and E Spangfort ldquoTherelationship between craniofacial morphology head postureand spinal curvature in 8 11 and 15-year-old childrenrdquo EuropeanJournal of Orthodontics vol 9 no 4 pp 254ndash264 1987

[7] J Huggare ldquoA cross-sectional study of head posture andcraniofacial growth in children from the north of Finlandrdquo

Proceedings of the Finnish Dental Society vol 83 no 1 pp 5ndash15 1987

[8] J Huggare and P Houghton ldquoAssociations between atlantoaxialand craniomandibular anatomyrdquo Growth Development andAging vol 60 no 1 pp 21ndash30 1996

[9] A Wenzel E Hojensgaard and J M Henriksen ldquoCraniofacialmorphology and head posture in children with asthma andperennial rhinitisrdquo European Journal of Orthodontics vol 7 no2 pp 83ndash92 1985

[10] L Sonnesen M Bakke and B Solow ldquoTemporomandibulardisorders in relation to craniofacial dimensions head postureand bite force in children selected for orthodontic treatmentrdquoEuropean Journal of Orthodontics vol 23 no 2 pp 179ndash1922001

[11] C M Visscher W De Boer F Lobbezoo L L M H HabetsandMNaeije ldquoIs there a relationship between head posture andcraniomandibular painrdquo Journal of Oral Rehabilitation vol 29no 11 pp 1030ndash1036 2002

[12] H Treuenfels ldquoDie Relation von Atlasposition prognather undprogener Kieferanomalierdquo Fortschritte der Kieferorthopadie vol43 no 1 p 82 1982

[13] U Gustavsson G Hansson A Holmqvist and M LundbergldquoHyoid bone position in relation to head posturerdquo SwedishDental Journal vol 65 no 8 pp 423ndash430 1972

[14] J W Pim Valk A J J Zonnenberg C J van Maanen and OG T van Wonderen ldquoThe biomechanical effects of a sagittalsplit ramus osteotomy on the relationship of the mandible thehyoid bone and the cervical spinerdquo The American Journal ofOrthodontics and Dentofacial Orthopedics vol 102 no 2 pp99ndash108 1992

[15] A Tallgren and B Solow ldquoHyoid bone position facial mor-phology and head posture in adultsrdquo European Journal ofOrthodontics vol 9 no 1 pp 1ndash8 1987

[16] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo AmericanJournal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[17] G J Romanes Cunninghamrsquos Manual of Practical Anatomy vol3 Oxford University Press New York NY USA 14th edition1983

[18] L W Graber ldquoHyoid changes following orthopedic treatmentof mandibular prognathismrdquo Angle Orthodontist vol 48 no 1pp 33ndash38 1978

[19] KMHiiemae SMHayenga andA Reese ldquoPatterns of tongueand jawmovement in a cinefluorographic study of feeding in themacaquerdquo Archives of Oral Biology vol 40 no 3 pp 229ndash2461995

[20] J Spiro J K Rendell and T Gay ldquoActivation and coordinationpatterns of the suprahyoid muscles during swallowingrdquo Laryn-goscope vol 104 no 11 I pp 1376ndash1382 1994

[21] H Tsai ldquoThe positional changes of hyoid bone in childrenrdquoTheJournal of Clinical Pediatric Dentistry vol 27 no 1 pp 29ndash342002

[22] B Fromm and M Lundberg ldquoPostural behaviour of the hyoidbone in normal occlusion and before and after surgical correc-tion of mandibular protrusionrdquo Swedish Dental Journal vol 63no 6 pp 425ndash433 1970

[23] H Opdebeeck W H Bell J Eisenfeld and D MishelevichldquoComparative study between the SFS and LFS rotation as apossible morphogenic mechanismrdquo The American Journal ofOrthodontics vol 74 no 5 pp 509ndash521 1978

8 The Scientific World Journal

[24] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in Class I and Class III malocclusionsrdquo Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol101 no 4 pp 308ndash312 1992

[25] S Carlsoo and G Leijon ldquoA radiographic study of the positionof the hyo-Iaryngeal complex in relation to the skull and thecervical column in manrdquo Transactions Royal Schools DentistryStockholm and Umeft vol 5 pp 13ndash34 1960

[26] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo TheAmerican Journal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[27] K J Showfety P S Vig and S Matteson ldquoA simple method fortaking natural-head-position cephalogramsrdquo American Journalof Orthodontics vol 83 no 6 pp 495ndash500 1983

[28] C C Steiner ldquoCephalometrics for you and merdquo The AmericanJournal of Orthodontics vol 39 no 10 pp 729ndash755 1953

[29] C C Steiner ldquoCephalometrics in clinical practicerdquo The AngleOrthodontist vol 29 no 1 pp 8ndash29 1959

[30] C C Steiner ldquoThe use of cephalometrics as an aid to planningand assessing orthodontic treatment Report of a caserdquo TheAmerican Journal of Orthodontics vol 46 no 10 pp 721ndash7351960

[31] I Ceylan ldquoFarklı Iskelet yapılarında dik yon kranyo-fasiyalmorfoloji hyoid kemigin konumu ve birinci servikal verte-branın morfolojisinin incelenmesirdquo Turk Ortodonti Dernegivol 8 no 1 pp 20ndash29 1995

[32] A G Brodie ldquoAnatomy and physiology of head and neckmusculaturerdquoTheAmerican Journal of Orthodontics vol 36 no11 pp 831ndash844 1950

[33] E Atik and I Kocadereli ldquoCraniofacial morphology head pos-ture and hyoid bone positionrdquo Turkish Journal of Orthodonticsvol 24 no 3 pp 237ndash246 2011

[34] J A Ogden ldquoRadiology of postnatal skeletal development XIThe first cervical vertebrardquo Skeletal Radiology vol 12 no 1 pp12ndash20 1984

[35] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in class I and class III malocclusionsrdquo TheAmerican Journal of Orthodontics and Dentofacial Orthopedicsvol 101 no 4 pp 308ndash312 1992

[36] B Solow S Siersbaek-Nielsen and E Greve ldquoAirway adequacyhead posture and craniofacial morphologyrdquo American Journalof Orthodontics vol 86 no 3 pp 214ndash223 1984

[37] S Valenzuela R Miralles M J Ravera et al ldquoDoes headposture have a significant effect on the hyoid bone positionand sternocleidomastoid electromyographic activity in youngadultsrdquo Journal of Craniomandibular Practice vol 23 no 3 pp204ndash211 2005

[38] R Surucu S Aras and A Soytarhan ldquoCephalometric evalua-tion of the immediate changes in cervical structures after theapplication of the activatorrdquo Turkish Journal of Orthodonticsvol 3 no 2 pp 44ndash49 1990

[39] N EggenspergerW Smolka and T Iizuka ldquoLong-term changesof hyoid bone position and pharyngeal airway size followingmandibular setback by sagittal split ramus osteotomyrdquo Journalof Cranio-Maxillofacial Surgery vol 33 no 2 pp 111ndash117 2005

[40] G Marsan E Oztas N Cura S Vasfi Kuvat and U EmeklildquoChanges in head posture and hyoid bone position in Turkishclass III patients after mandibular setback surgeryrdquo Journal ofCranio-Maxillofacial Surgery vol 38 no 2 pp 113ndash121 2010

[41] A Gale P V J Kilpelainen andM T Laine-Alava ldquoHyoid boneposition after surgical mandibular advancementrdquo EuropeanJournal of Orthodontics vol 23 no 6 pp 695ndash701 2001

[42] B Solow and A Tallgren ldquoHead posture and craniofacialmorphologyrdquo The American Journal of Physical Anthropologyvol 44 no 3 pp 417ndash435 1976

[43] N B Haralabakis NM Toutountzakis and S C Yiagtzis ldquoThehyoid bone position in adult individuals with open bite andnormal occlusionrdquoEuropean Journal of Orthodontics vol 15 no4 pp 265ndash271 1993

[44] I Ceylan and H Oktay ldquoA study on the pharyngeal size in dif-ferent skeletal patternsrdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 108 no 1 pp 69ndash75 1995

[45] Y H Kim and J J Vietas ldquoAnteroposterior dysplasia indicatoran adjunct to cephalometric differential diagnosisrdquoThe Ameri-can Journal of Orthodontics vol 73 no 6 pp 619ndash633 1978

[46] W Hussels and R S Nanda ldquoAnalysis of factors affecting angleANBrdquo American Journal of Orthodontics vol 85 no 5 pp 411ndash423 1984

[47] H Oktay ldquoA comparison of ANBWits AF-BF and APDI mea-surementsrdquo American Journal of Orthodontics and DentofacialOrthopedics vol 104 no 2 pp 584ndash591 1991

[48] M M Ozbek and A Koklu ldquoNatural cervical inclination andcraniofacial structurerdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 104 no 6 pp 584ndash591 1993

[49] H Fjellvang and B Solow ldquoCraniocervical postural relationsand craniofacial morphology in 30 blind subjectsrdquo The Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol90 no 4 pp 327ndash334 1986

[50] A M Sahin Saglam and N E Uydas ldquoRelationship betweenhead posture and hyoid position in adult females and malesrdquoJournal of Cranio-Maxillofacial Surgery vol 34 no 2 pp 85ndash92 2006

[51] I Ceylan Degisik ANB Acılarında Dogal BasKonumu ve HyoidKemiginin Konumunun Incelenmesi Ataturk Universitesi SaglıkBilimleri Enstitusu Ortodonti Anabilim Dalı 1990

[52] B Dincer A Erdinc G Oncag and S Dogan ldquoThe investiga-tion of the hyoid bone position in class 1 class 2 division 1 andclass 3 malocclusionrdquo Turkish Journal of Orthodontics vol 13pp 108ndash115 2000

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Case Reports in Dentistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral ImplantsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anesthesiology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Radiology Research and Practice

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Dental SurgeryJournal of

Drug DeliveryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral DiseasesJournal of

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Computational and Mathematical Methods in Medicine

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PainResearch and TreatmentHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Preventive MedicineAdvances in

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EndocrinologyInternational Journal of

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OrthopedicsAdvances in

Page 4: Research Article Cephalometric Investigation of First Cervical Vertebrae Morphology ...downloads.hindawi.com/journals/tswj/2014/159784.pdf ·  · 2015-11-22Research Article Cephalometric

4 The Scientific World Journal

Table4Intragroup

comparis

onof

malea

ndfemalep

artic

ipants

Measurements

ClassI

ClassII

ClassIII

Female(119899=20)

Male(119899=20)

(119875value)

Female(119899=20)

Male(119899=20)

(119875value)

Female(119899=20)

Male(119899=20)

(119875value)

Mean

SDMean

SDMean

SDMean

SDMean

SDMean

SDSN

A(∘ )

8080

446

8360

503

0268

NS

8330

539

8337

381

0858

NS

7900

485

7677

435

0434

NS

SNB(∘ )

7790

448

8040

485

0053

NS

7660

560

7643

335

0858

NS

8080

391

7888

416

0510

NS

ANB(∘ )

290

128

320

101

0240

NS

670

067

693

104

0776

NSminus18

0204

minus211

078

0127

NS

HyHy1015840MD(∘ )

770

537

540

291

0424

NS

840

389

1175

954

0624

NS

840

537

1177

993

0624

NS

Hy-NSL

(mm)

10370

427

12060

791

000

0lowastlowastlowast

10560

554

11887

1052

000

6lowastlowast

10600

522

11966

756

0001lowastlowast

HyNL(m

m)

5950

467

7110

667

0001lowastlowast

6350

667

7162

930

0050lowast

6210

508

7177

624

0003lowastlowast

Hy-CV

T(m

m)

4940

279

5930

266

000

0lowastlowastlowast

5020

278

5612

164

0001lowastlowast

4990

268

5866

327

000

0lowastlowastlowast

HyPo

g(mm)

5490

818

5110

360

0196

NS

5160

356

5025

647

096

4NS

5190

540

4977

591

0566

NS

HyMe(mm)

4910

724

4360

368

0063

NS

4440

394

4275

625

0562

NS

4520

431

4366

593

0623

NS

119883(m

m)

800

163

1170

262

000

4lowastlowast

860

195

937

287

0743

NS

910

213

822

263

0677

NS

119884(m

m)

830

125

1040

171

0012lowast

870

149

975

237

0470

NS

850

143

966

122

0077

NS

119885(m

m)

700

221

730

226

0908

NS

650

241

587

241

0369

NS

780

147

911

161

0086

NS

LUM

(mm)

2790

272

3120

229

0013lowast

284

222

2987

285

0227

NS

2900

309

3400

683

0027lowast

a-p(m

m)

4690

185

5190

246

0001lowastlowast

4850

201

5075

399

0192

NS

4740

241

4988

664

0029lowast

lowast

119875lt005lowastlowast

119875lt001lowastlowastlowast

119875lt0001NSno

nsignificantSD

stand

arddeviation

and119899num

bero

fpatients

The Scientific World Journal 5

Table 5 Intergroup comparison of mean differences among males with Class I II and III skeletal patterns

Measurements Class I (119899 = 20) Class II (119899 = 20) Class III (119899 = 20) ANOVA Multiple comparison LSD test (119875 value)Mean SD Mean SD Mean SD CI-CII CII-CIII CI-CIII

SNA (∘) 8360 503 8338 381 7678 435 lowastlowast 0917 0006 0003SNB (∘) 8040 485 7644 335 7889 416 NS 0060 0245 0445ANB (∘) 320 131 694 114 minus211 078 lowastlowastlowast 0000 0000 0000Hy Hy1015840 MD (∘) 540 291 1175 954 1178 993 NS 0104 0994 0092Hy NSL (mm) 12060 791 11888 1052 11967 756 NS 0678 0852 0816Hy NL (mm) 7110 667 7162 930 7178 624 NS 0883 0967 0844Hy-CVT (mm) 5930 266 5612 164 5967 227 lowast 0019 0060 0608Hy Pog (mm) 5110 360 5025 647 4978 591 NS 0741 0858 0596Hy Me (mm) 4360 368 4275 625 4367 593 NS 0739 0726 0978119883 (mm) 1170 262 938 287 822 263 lowast 0082 0389 0010119884 (mm) 1040 171 975 237 967 122 NS 0454 0925 0384119885 (mm) 730 226 588 241 911 161 lowast 0169 0004 0075LUM (mm) 3120 230 2988 285 3400 683 NS 0537 0069 0185a-p (mm) 5190 247 5075 399 4989 664 NS 0607 0707 0356lowast

119875 lt 005 lowastlowast119875 lt 001 lowastlowastlowast119875 lt 0001 NS statistically not significant SD standard deviation and 119899 number of patients

Table 6 Intergroup comparison of mean differences among females with Class I II and III skeletal patterns

Measurements Class I (119899 = 20) Class II (119899 = 20) Class III (119899 = 20) ANOVA Multiple comparison LSD test (119875 value)Mean SD Mean SD Mean SD CI-CII CII-CIII CI-CIII

SNA (∘) 8080 446 8330 539 7900 485 NS 0266 0061 0421SNB (∘) 7790 448 7660 56 8080 391 NS 0895 0072 0094ANB (∘) 290 128 670 067 minus180 104 lowastlowastlowast 0000 0000 0000Hy Hy1015840 MD (∘) 770 537 840 389 840 537 NS 0753 1000 0753Hy NSL (mm) 10370 427 10560 554 10600 522 NS 0407 0861 0317Hy NL (mm) 5950 467 6350 667 6210 508 NS 0118 0577 0304Hy-CVT (mm) 4940 279 5020 278 4990 268 NS 0522 0809 0688Hy Pog (mm) 5490 818 5160 356 5190 540 NS 0231 0912 0275Hy Me (mm) 4910 724 4440 395 4520 431 NS 0061 0742 0117119883 (mm) 800 163 860 195 910 213 NS 0490 0565 0211119884 (mm) 830 125 870 149 850 143 NS 0527 0751 0751119885 (mm) 700 221 65 241 78 147 NS 0594 0172 0396LUM (mm) 2790 272 284 222 2900 309 NS 0682 0624 0371a-p (mm) 4690 185 4850 201 4740 241 NS 0101 0253 0600lowastlowastlowast

119875 lt 0001 NS statistically not significant SD standard deviation and 119899 number of patients

of C1 was positioned more inferiorly among participantswith Class I versus Class III skeletal patterns C1 was alsocloser to C2 among participants of Class II versus ClassIII skeletal patterns In contrast the intergroup comparisonamong female participants revealed a significant difference inonly the ANB measurement among the groups

4 Discussion

The position of the hyoid bone is of great clinical interestbecause it plays an important role in maintaining the dimen-sions of the upper airway and an upright natural head posture

[26 32 33] The first cervical vertebra also known as theatlas represents the transition between the skull and the axialskeleton and it is reported that the dimensions of this vertebraaffect aspects of both the facial skeleton and the cervicalcolumn [34] Numerous previous studies have shown thatorthodontic treatments impacting mandibular position canalso alter the position of the hyoid given that it is attachedto the mandible via the geniohyoid anterior digastric andmylohyoid muscles [35ndash37]

Graber [18] evaluated the position of the hyoid in 30children (16 males and 14 females mean age of 6 years) afterorthopedic treatment for mandibular prognathism Graberobserved that the hyoid position had shifted posteriorly

6 The Scientific World Journal

and inferiorly at 3 years after treatment Surucu et al [38]examined 10 individuals with skeletal Class II division Imalocclusions and found that after the activator was appliedand the bite was opened the tongue shifted posteriorly andcaused constriction of the upper airway To compensate forthis constriction patients would need to alter their normalupright head posture by extending the headjawThe authorsreported that as a result of these changes the mandiblemoved into a more anterior position while the hyoid shiftedanteriorly depending on the degree of head extension It hasbeen reported that the hyoidmoves posteriorly and inferiorlyin mandibular setback surgeries [39 40] This subsequentlyresults in the base of the tongue shifting posteriorly andinferiorly resulting in constriction of the upper airway andforcing the patient to further extend the head positionto lengthen the upper airway Posterior movement of themandible can cause relaxation of the suprahyoidmusculaturewhich may instigate balance disorders in the head and neckmuscles and oropharyngeal complex It has been postulatedthat if this relaxation continues for an extended period it canalter the position of the hyoid as well as the length of thesuprahyoid muscle causing skeletal relapse [41]

Cephalometric radiography one of the most importanttools in orthodontics both clinically and in research permitsthe accurate evaluation of the dental skeletal and soft tissuerelationships of the craniofacial complex before the initiationof treatment and during growth [42ndash44]

In light of this information the aim of this study wasto document the position of the hyoid bone and cervicalatlas morphology on the cephalometric radiographs of par-ticipants with different sagittal skeletal patterns with the goalof identifying cephalometric norms To achieve this partic-ipants were classified according to horizontal discrepanciesobserved in the ANB angle a parameter that is widely usedin the evaluation of skeletal anterior-posterior relationships[45ndash47] Previous studies have shown that natural headposture is related to respiratory [48] and visual function[49] Therefore to determine natural head posture in aprecise manner only individuals without visual hearing orrespiratory disturbances were included in this study

Our results from the intragroup comparison of Class Iand Class II participants revealed that several measurementswere significantly larger in males than in females Theseincluded Hy-NSL (119875 lt 0001) Hy-PD (119875 = 0001) andHy-CVT (119875 lt 0001) In addition the hyoid was positionedmore anteriorly and inferiorly in males than in femalesSahin Saglam and Uydas [50] investigated variation in hyoidposition and head posture between genders (38 females and38 males) using lateral cephalometric films obtained using anatural head position All participants had a Class I skeletalpattern and ideal dental occlusion The authors found thatnatural head position did not differ between genders but thehyoid bone was positioned more superiorly and posteriorlyin females compared to males Ceylan [51] examined 90adolescents including 45 boys and 45 girls aged 13ndash15 yearsand analyzed the relationship of the ANB angle and naturalhead position to the position of the hyoid bone Naturalhead position was not significantly affected by gender butthe hyoid bone was positioned significantly more superiorly

and posteriorly in females than in males These results areconsistent with the data reported here

In the intragroup comparison of Class I participantssignificant differences were observed with respect to the 119883119884 Lum and a-p parameters all of which were smaller infemales The data also revealed a greater superior-posteriorarea of C1 shorter distance between C1 and C2 shorteranterior-posterior dimensions and shorter distance betweenthe anterior border of the C1 dorsal arch and the posteriorborder of the C2 odontoid process also in females Theseresults suggest that the male body is more developed than thefemale body

In the intragroup comparison of Class III participantsit was found that the hyoid bone was positioned moreanteriorly and inferiorly in males than in females Cervicaland craniocervical posture may be one factor explaining thesignificant differences observed between males and femaleswho have Class III malocclusions [24] Females who haveClass III malocclusions show amuchmore ldquonormalrdquo positionof the hyoid bone as compared to males with Class IIImalocclusions This may be due to heightened aestheticawareness of a prognathic mandible in girls which leadsthem to assume quite early in life a modified head postureallowing them to minimize the appearance of a prominentchin

Intergroup comparisons of differences between gendersshowed statistically significant differences in ANB measure-ments in all groups These results are unsurprising giventhat participants with normal vertical patterns and differentANB values were included in this study In the intergroupcomparison of males the Hy-CVT distance was found to begreater in Class I than in Class II participants This indicatespronounced anterior positioning of the hyoid bone in Class Imales On the other hand Ceylan [31] evaluated the hyoidbone position in different skeletal patterns of adolescentsaged 13ndash15 years and reported that the hyoid bone waspositionedmore anteriorlywith an increase in theANBangleThis is in direct contrast to our study whichmay be the resultof examining different age groups (adolescents versus youngadults) and the inclusion of participants with normal verticalskeletal patterns in our work Dincer et al [52] investigatedthe position of the hyoid bone with respect to its relationshipwith the dentofacial system in 45 participants with ClassI Class II division I and Class III malocclusions It wasascertained that the hyoid was positioned more posteriorlyamong participants with a Class II division I skeletal patterncompared to a Class I pattern and more anteriorly amongparticipants with a Class III skeletal pattern compared toa Class I pattern In addition the greater 119883 values amongClass I versus Class III participants indicate an overall lowerposition of C1 in the Class I group Class III participants hadhigher 119885 values compared to the Class II group accordinglythe distance between the posterior part of C1 andC2 is greaterin Class III versus Class II participants

Regarding skeletal patterns in female participants no dif-ference was observed for parameters relating to the hyoid orC1 indicating nomorphological difference in these structuresamong females Consistent with our findings Adamidis andSpyropoulos [24] found no statistically significant differences

The Scientific World Journal 7

in the position or orientation of the hyoid among femalesexhibiting Class I malocclusions versus those with Class IIImalocclusions

5 Conclusions

This study revealed that the hyoid bone is positioned moreinferiorly and anteriorly and is more prominent in malesthan in females regardless of variation in the axial skeletonC1 was also larger along the anterior-posterior axis in malesexhibiting a Class I skeletal pattern compared to females inthe same class However no significant difference in hyoidposition or C1 morphology was observed in relation to theANB in females In the sagittal plane the hyoid bone wassimilar in males with a Class I or Class III skeletal patternbut was positioned more posteriorly based on mandibularbone development in males with Class I skeletal patterns Inaddition the vertical position of C1 varied depending on thesagittal skeletal pattern among male participants

It is especially important among males that the hyoidbone remains in the same position after orthodontic andorthognathic treatment so that the balance of the soft tissuesis not altered thus reducing the chance of relapse Theresults of this study are therefore highly useful for clinicianswho must assess the stability of these structures in patientswho are candidates for orthognathic or orthopedic surgerywhich may help to prevent the obstruction of the upperairway In addition this study helps to identify cephalometricnorms that exist amongmales and females who have differentskeletal sagittal anomalies

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] A G Brodie ldquoEmerging concepts of facial growthrdquo AngleOrthodontist vol 41 no 2 pp 103ndash118 1971

[2] D K Bailey ldquoThenormal cervical spine in infants and childrenrdquoRadiology vol 59 no 5 pp 712ndash719 1952

[3] S W Gray C B Romanie and J E Skandalakis ldquoCongenitalfusion of the cervical vertebraerdquo Surgery Gynecology amp Obstet-rics vol 118 pp 373ndash385 1964

[4] J Huggare ldquoAssociation between morphology of the firstcervical vertebra head posture and craniofacial structuresrdquoEuropean Journal of Orthodontics vol 13 no 6 pp 435ndash4401991

[5] M Sandikcioglu S Skov and B Solow ldquoAtlas morphologyin relation to craniofacial morphology and head posturerdquoEuropean Journal ofOrthodontics vol 16 no 2 pp 96ndash103 1994

[6] E Hellsing J McWilliam T Reigo and E Spangfort ldquoTherelationship between craniofacial morphology head postureand spinal curvature in 8 11 and 15-year-old childrenrdquo EuropeanJournal of Orthodontics vol 9 no 4 pp 254ndash264 1987

[7] J Huggare ldquoA cross-sectional study of head posture andcraniofacial growth in children from the north of Finlandrdquo

Proceedings of the Finnish Dental Society vol 83 no 1 pp 5ndash15 1987

[8] J Huggare and P Houghton ldquoAssociations between atlantoaxialand craniomandibular anatomyrdquo Growth Development andAging vol 60 no 1 pp 21ndash30 1996

[9] A Wenzel E Hojensgaard and J M Henriksen ldquoCraniofacialmorphology and head posture in children with asthma andperennial rhinitisrdquo European Journal of Orthodontics vol 7 no2 pp 83ndash92 1985

[10] L Sonnesen M Bakke and B Solow ldquoTemporomandibulardisorders in relation to craniofacial dimensions head postureand bite force in children selected for orthodontic treatmentrdquoEuropean Journal of Orthodontics vol 23 no 2 pp 179ndash1922001

[11] C M Visscher W De Boer F Lobbezoo L L M H HabetsandMNaeije ldquoIs there a relationship between head posture andcraniomandibular painrdquo Journal of Oral Rehabilitation vol 29no 11 pp 1030ndash1036 2002

[12] H Treuenfels ldquoDie Relation von Atlasposition prognather undprogener Kieferanomalierdquo Fortschritte der Kieferorthopadie vol43 no 1 p 82 1982

[13] U Gustavsson G Hansson A Holmqvist and M LundbergldquoHyoid bone position in relation to head posturerdquo SwedishDental Journal vol 65 no 8 pp 423ndash430 1972

[14] J W Pim Valk A J J Zonnenberg C J van Maanen and OG T van Wonderen ldquoThe biomechanical effects of a sagittalsplit ramus osteotomy on the relationship of the mandible thehyoid bone and the cervical spinerdquo The American Journal ofOrthodontics and Dentofacial Orthopedics vol 102 no 2 pp99ndash108 1992

[15] A Tallgren and B Solow ldquoHyoid bone position facial mor-phology and head posture in adultsrdquo European Journal ofOrthodontics vol 9 no 1 pp 1ndash8 1987

[16] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo AmericanJournal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[17] G J Romanes Cunninghamrsquos Manual of Practical Anatomy vol3 Oxford University Press New York NY USA 14th edition1983

[18] L W Graber ldquoHyoid changes following orthopedic treatmentof mandibular prognathismrdquo Angle Orthodontist vol 48 no 1pp 33ndash38 1978

[19] KMHiiemae SMHayenga andA Reese ldquoPatterns of tongueand jawmovement in a cinefluorographic study of feeding in themacaquerdquo Archives of Oral Biology vol 40 no 3 pp 229ndash2461995

[20] J Spiro J K Rendell and T Gay ldquoActivation and coordinationpatterns of the suprahyoid muscles during swallowingrdquo Laryn-goscope vol 104 no 11 I pp 1376ndash1382 1994

[21] H Tsai ldquoThe positional changes of hyoid bone in childrenrdquoTheJournal of Clinical Pediatric Dentistry vol 27 no 1 pp 29ndash342002

[22] B Fromm and M Lundberg ldquoPostural behaviour of the hyoidbone in normal occlusion and before and after surgical correc-tion of mandibular protrusionrdquo Swedish Dental Journal vol 63no 6 pp 425ndash433 1970

[23] H Opdebeeck W H Bell J Eisenfeld and D MishelevichldquoComparative study between the SFS and LFS rotation as apossible morphogenic mechanismrdquo The American Journal ofOrthodontics vol 74 no 5 pp 509ndash521 1978

8 The Scientific World Journal

[24] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in Class I and Class III malocclusionsrdquo Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol101 no 4 pp 308ndash312 1992

[25] S Carlsoo and G Leijon ldquoA radiographic study of the positionof the hyo-Iaryngeal complex in relation to the skull and thecervical column in manrdquo Transactions Royal Schools DentistryStockholm and Umeft vol 5 pp 13ndash34 1960

[26] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo TheAmerican Journal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[27] K J Showfety P S Vig and S Matteson ldquoA simple method fortaking natural-head-position cephalogramsrdquo American Journalof Orthodontics vol 83 no 6 pp 495ndash500 1983

[28] C C Steiner ldquoCephalometrics for you and merdquo The AmericanJournal of Orthodontics vol 39 no 10 pp 729ndash755 1953

[29] C C Steiner ldquoCephalometrics in clinical practicerdquo The AngleOrthodontist vol 29 no 1 pp 8ndash29 1959

[30] C C Steiner ldquoThe use of cephalometrics as an aid to planningand assessing orthodontic treatment Report of a caserdquo TheAmerican Journal of Orthodontics vol 46 no 10 pp 721ndash7351960

[31] I Ceylan ldquoFarklı Iskelet yapılarında dik yon kranyo-fasiyalmorfoloji hyoid kemigin konumu ve birinci servikal verte-branın morfolojisinin incelenmesirdquo Turk Ortodonti Dernegivol 8 no 1 pp 20ndash29 1995

[32] A G Brodie ldquoAnatomy and physiology of head and neckmusculaturerdquoTheAmerican Journal of Orthodontics vol 36 no11 pp 831ndash844 1950

[33] E Atik and I Kocadereli ldquoCraniofacial morphology head pos-ture and hyoid bone positionrdquo Turkish Journal of Orthodonticsvol 24 no 3 pp 237ndash246 2011

[34] J A Ogden ldquoRadiology of postnatal skeletal development XIThe first cervical vertebrardquo Skeletal Radiology vol 12 no 1 pp12ndash20 1984

[35] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in class I and class III malocclusionsrdquo TheAmerican Journal of Orthodontics and Dentofacial Orthopedicsvol 101 no 4 pp 308ndash312 1992

[36] B Solow S Siersbaek-Nielsen and E Greve ldquoAirway adequacyhead posture and craniofacial morphologyrdquo American Journalof Orthodontics vol 86 no 3 pp 214ndash223 1984

[37] S Valenzuela R Miralles M J Ravera et al ldquoDoes headposture have a significant effect on the hyoid bone positionand sternocleidomastoid electromyographic activity in youngadultsrdquo Journal of Craniomandibular Practice vol 23 no 3 pp204ndash211 2005

[38] R Surucu S Aras and A Soytarhan ldquoCephalometric evalua-tion of the immediate changes in cervical structures after theapplication of the activatorrdquo Turkish Journal of Orthodonticsvol 3 no 2 pp 44ndash49 1990

[39] N EggenspergerW Smolka and T Iizuka ldquoLong-term changesof hyoid bone position and pharyngeal airway size followingmandibular setback by sagittal split ramus osteotomyrdquo Journalof Cranio-Maxillofacial Surgery vol 33 no 2 pp 111ndash117 2005

[40] G Marsan E Oztas N Cura S Vasfi Kuvat and U EmeklildquoChanges in head posture and hyoid bone position in Turkishclass III patients after mandibular setback surgeryrdquo Journal ofCranio-Maxillofacial Surgery vol 38 no 2 pp 113ndash121 2010

[41] A Gale P V J Kilpelainen andM T Laine-Alava ldquoHyoid boneposition after surgical mandibular advancementrdquo EuropeanJournal of Orthodontics vol 23 no 6 pp 695ndash701 2001

[42] B Solow and A Tallgren ldquoHead posture and craniofacialmorphologyrdquo The American Journal of Physical Anthropologyvol 44 no 3 pp 417ndash435 1976

[43] N B Haralabakis NM Toutountzakis and S C Yiagtzis ldquoThehyoid bone position in adult individuals with open bite andnormal occlusionrdquoEuropean Journal of Orthodontics vol 15 no4 pp 265ndash271 1993

[44] I Ceylan and H Oktay ldquoA study on the pharyngeal size in dif-ferent skeletal patternsrdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 108 no 1 pp 69ndash75 1995

[45] Y H Kim and J J Vietas ldquoAnteroposterior dysplasia indicatoran adjunct to cephalometric differential diagnosisrdquoThe Ameri-can Journal of Orthodontics vol 73 no 6 pp 619ndash633 1978

[46] W Hussels and R S Nanda ldquoAnalysis of factors affecting angleANBrdquo American Journal of Orthodontics vol 85 no 5 pp 411ndash423 1984

[47] H Oktay ldquoA comparison of ANBWits AF-BF and APDI mea-surementsrdquo American Journal of Orthodontics and DentofacialOrthopedics vol 104 no 2 pp 584ndash591 1991

[48] M M Ozbek and A Koklu ldquoNatural cervical inclination andcraniofacial structurerdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 104 no 6 pp 584ndash591 1993

[49] H Fjellvang and B Solow ldquoCraniocervical postural relationsand craniofacial morphology in 30 blind subjectsrdquo The Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol90 no 4 pp 327ndash334 1986

[50] A M Sahin Saglam and N E Uydas ldquoRelationship betweenhead posture and hyoid position in adult females and malesrdquoJournal of Cranio-Maxillofacial Surgery vol 34 no 2 pp 85ndash92 2006

[51] I Ceylan Degisik ANB Acılarında Dogal BasKonumu ve HyoidKemiginin Konumunun Incelenmesi Ataturk Universitesi SaglıkBilimleri Enstitusu Ortodonti Anabilim Dalı 1990

[52] B Dincer A Erdinc G Oncag and S Dogan ldquoThe investiga-tion of the hyoid bone position in class 1 class 2 division 1 andclass 3 malocclusionrdquo Turkish Journal of Orthodontics vol 13pp 108ndash115 2000

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Case Reports in Dentistry

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Oral ImplantsJournal of

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Radiology Research and Practice

Environmental and Public Health

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral DiseasesJournal of

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OrthopedicsAdvances in

Page 5: Research Article Cephalometric Investigation of First Cervical Vertebrae Morphology ...downloads.hindawi.com/journals/tswj/2014/159784.pdf ·  · 2015-11-22Research Article Cephalometric

The Scientific World Journal 5

Table 5 Intergroup comparison of mean differences among males with Class I II and III skeletal patterns

Measurements Class I (119899 = 20) Class II (119899 = 20) Class III (119899 = 20) ANOVA Multiple comparison LSD test (119875 value)Mean SD Mean SD Mean SD CI-CII CII-CIII CI-CIII

SNA (∘) 8360 503 8338 381 7678 435 lowastlowast 0917 0006 0003SNB (∘) 8040 485 7644 335 7889 416 NS 0060 0245 0445ANB (∘) 320 131 694 114 minus211 078 lowastlowastlowast 0000 0000 0000Hy Hy1015840 MD (∘) 540 291 1175 954 1178 993 NS 0104 0994 0092Hy NSL (mm) 12060 791 11888 1052 11967 756 NS 0678 0852 0816Hy NL (mm) 7110 667 7162 930 7178 624 NS 0883 0967 0844Hy-CVT (mm) 5930 266 5612 164 5967 227 lowast 0019 0060 0608Hy Pog (mm) 5110 360 5025 647 4978 591 NS 0741 0858 0596Hy Me (mm) 4360 368 4275 625 4367 593 NS 0739 0726 0978119883 (mm) 1170 262 938 287 822 263 lowast 0082 0389 0010119884 (mm) 1040 171 975 237 967 122 NS 0454 0925 0384119885 (mm) 730 226 588 241 911 161 lowast 0169 0004 0075LUM (mm) 3120 230 2988 285 3400 683 NS 0537 0069 0185a-p (mm) 5190 247 5075 399 4989 664 NS 0607 0707 0356lowast

119875 lt 005 lowastlowast119875 lt 001 lowastlowastlowast119875 lt 0001 NS statistically not significant SD standard deviation and 119899 number of patients

Table 6 Intergroup comparison of mean differences among females with Class I II and III skeletal patterns

Measurements Class I (119899 = 20) Class II (119899 = 20) Class III (119899 = 20) ANOVA Multiple comparison LSD test (119875 value)Mean SD Mean SD Mean SD CI-CII CII-CIII CI-CIII

SNA (∘) 8080 446 8330 539 7900 485 NS 0266 0061 0421SNB (∘) 7790 448 7660 56 8080 391 NS 0895 0072 0094ANB (∘) 290 128 670 067 minus180 104 lowastlowastlowast 0000 0000 0000Hy Hy1015840 MD (∘) 770 537 840 389 840 537 NS 0753 1000 0753Hy NSL (mm) 10370 427 10560 554 10600 522 NS 0407 0861 0317Hy NL (mm) 5950 467 6350 667 6210 508 NS 0118 0577 0304Hy-CVT (mm) 4940 279 5020 278 4990 268 NS 0522 0809 0688Hy Pog (mm) 5490 818 5160 356 5190 540 NS 0231 0912 0275Hy Me (mm) 4910 724 4440 395 4520 431 NS 0061 0742 0117119883 (mm) 800 163 860 195 910 213 NS 0490 0565 0211119884 (mm) 830 125 870 149 850 143 NS 0527 0751 0751119885 (mm) 700 221 65 241 78 147 NS 0594 0172 0396LUM (mm) 2790 272 284 222 2900 309 NS 0682 0624 0371a-p (mm) 4690 185 4850 201 4740 241 NS 0101 0253 0600lowastlowastlowast

119875 lt 0001 NS statistically not significant SD standard deviation and 119899 number of patients

of C1 was positioned more inferiorly among participantswith Class I versus Class III skeletal patterns C1 was alsocloser to C2 among participants of Class II versus ClassIII skeletal patterns In contrast the intergroup comparisonamong female participants revealed a significant difference inonly the ANB measurement among the groups

4 Discussion

The position of the hyoid bone is of great clinical interestbecause it plays an important role in maintaining the dimen-sions of the upper airway and an upright natural head posture

[26 32 33] The first cervical vertebra also known as theatlas represents the transition between the skull and the axialskeleton and it is reported that the dimensions of this vertebraaffect aspects of both the facial skeleton and the cervicalcolumn [34] Numerous previous studies have shown thatorthodontic treatments impacting mandibular position canalso alter the position of the hyoid given that it is attachedto the mandible via the geniohyoid anterior digastric andmylohyoid muscles [35ndash37]

Graber [18] evaluated the position of the hyoid in 30children (16 males and 14 females mean age of 6 years) afterorthopedic treatment for mandibular prognathism Graberobserved that the hyoid position had shifted posteriorly

6 The Scientific World Journal

and inferiorly at 3 years after treatment Surucu et al [38]examined 10 individuals with skeletal Class II division Imalocclusions and found that after the activator was appliedand the bite was opened the tongue shifted posteriorly andcaused constriction of the upper airway To compensate forthis constriction patients would need to alter their normalupright head posture by extending the headjawThe authorsreported that as a result of these changes the mandiblemoved into a more anterior position while the hyoid shiftedanteriorly depending on the degree of head extension It hasbeen reported that the hyoidmoves posteriorly and inferiorlyin mandibular setback surgeries [39 40] This subsequentlyresults in the base of the tongue shifting posteriorly andinferiorly resulting in constriction of the upper airway andforcing the patient to further extend the head positionto lengthen the upper airway Posterior movement of themandible can cause relaxation of the suprahyoidmusculaturewhich may instigate balance disorders in the head and neckmuscles and oropharyngeal complex It has been postulatedthat if this relaxation continues for an extended period it canalter the position of the hyoid as well as the length of thesuprahyoid muscle causing skeletal relapse [41]

Cephalometric radiography one of the most importanttools in orthodontics both clinically and in research permitsthe accurate evaluation of the dental skeletal and soft tissuerelationships of the craniofacial complex before the initiationof treatment and during growth [42ndash44]

In light of this information the aim of this study wasto document the position of the hyoid bone and cervicalatlas morphology on the cephalometric radiographs of par-ticipants with different sagittal skeletal patterns with the goalof identifying cephalometric norms To achieve this partic-ipants were classified according to horizontal discrepanciesobserved in the ANB angle a parameter that is widely usedin the evaluation of skeletal anterior-posterior relationships[45ndash47] Previous studies have shown that natural headposture is related to respiratory [48] and visual function[49] Therefore to determine natural head posture in aprecise manner only individuals without visual hearing orrespiratory disturbances were included in this study

Our results from the intragroup comparison of Class Iand Class II participants revealed that several measurementswere significantly larger in males than in females Theseincluded Hy-NSL (119875 lt 0001) Hy-PD (119875 = 0001) andHy-CVT (119875 lt 0001) In addition the hyoid was positionedmore anteriorly and inferiorly in males than in femalesSahin Saglam and Uydas [50] investigated variation in hyoidposition and head posture between genders (38 females and38 males) using lateral cephalometric films obtained using anatural head position All participants had a Class I skeletalpattern and ideal dental occlusion The authors found thatnatural head position did not differ between genders but thehyoid bone was positioned more superiorly and posteriorlyin females compared to males Ceylan [51] examined 90adolescents including 45 boys and 45 girls aged 13ndash15 yearsand analyzed the relationship of the ANB angle and naturalhead position to the position of the hyoid bone Naturalhead position was not significantly affected by gender butthe hyoid bone was positioned significantly more superiorly

and posteriorly in females than in males These results areconsistent with the data reported here

In the intragroup comparison of Class I participantssignificant differences were observed with respect to the 119883119884 Lum and a-p parameters all of which were smaller infemales The data also revealed a greater superior-posteriorarea of C1 shorter distance between C1 and C2 shorteranterior-posterior dimensions and shorter distance betweenthe anterior border of the C1 dorsal arch and the posteriorborder of the C2 odontoid process also in females Theseresults suggest that the male body is more developed than thefemale body

In the intragroup comparison of Class III participantsit was found that the hyoid bone was positioned moreanteriorly and inferiorly in males than in females Cervicaland craniocervical posture may be one factor explaining thesignificant differences observed between males and femaleswho have Class III malocclusions [24] Females who haveClass III malocclusions show amuchmore ldquonormalrdquo positionof the hyoid bone as compared to males with Class IIImalocclusions This may be due to heightened aestheticawareness of a prognathic mandible in girls which leadsthem to assume quite early in life a modified head postureallowing them to minimize the appearance of a prominentchin

Intergroup comparisons of differences between gendersshowed statistically significant differences in ANB measure-ments in all groups These results are unsurprising giventhat participants with normal vertical patterns and differentANB values were included in this study In the intergroupcomparison of males the Hy-CVT distance was found to begreater in Class I than in Class II participants This indicatespronounced anterior positioning of the hyoid bone in Class Imales On the other hand Ceylan [31] evaluated the hyoidbone position in different skeletal patterns of adolescentsaged 13ndash15 years and reported that the hyoid bone waspositionedmore anteriorlywith an increase in theANBangleThis is in direct contrast to our study whichmay be the resultof examining different age groups (adolescents versus youngadults) and the inclusion of participants with normal verticalskeletal patterns in our work Dincer et al [52] investigatedthe position of the hyoid bone with respect to its relationshipwith the dentofacial system in 45 participants with ClassI Class II division I and Class III malocclusions It wasascertained that the hyoid was positioned more posteriorlyamong participants with a Class II division I skeletal patterncompared to a Class I pattern and more anteriorly amongparticipants with a Class III skeletal pattern compared toa Class I pattern In addition the greater 119883 values amongClass I versus Class III participants indicate an overall lowerposition of C1 in the Class I group Class III participants hadhigher 119885 values compared to the Class II group accordinglythe distance between the posterior part of C1 andC2 is greaterin Class III versus Class II participants

Regarding skeletal patterns in female participants no dif-ference was observed for parameters relating to the hyoid orC1 indicating nomorphological difference in these structuresamong females Consistent with our findings Adamidis andSpyropoulos [24] found no statistically significant differences

The Scientific World Journal 7

in the position or orientation of the hyoid among femalesexhibiting Class I malocclusions versus those with Class IIImalocclusions

5 Conclusions

This study revealed that the hyoid bone is positioned moreinferiorly and anteriorly and is more prominent in malesthan in females regardless of variation in the axial skeletonC1 was also larger along the anterior-posterior axis in malesexhibiting a Class I skeletal pattern compared to females inthe same class However no significant difference in hyoidposition or C1 morphology was observed in relation to theANB in females In the sagittal plane the hyoid bone wassimilar in males with a Class I or Class III skeletal patternbut was positioned more posteriorly based on mandibularbone development in males with Class I skeletal patterns Inaddition the vertical position of C1 varied depending on thesagittal skeletal pattern among male participants

It is especially important among males that the hyoidbone remains in the same position after orthodontic andorthognathic treatment so that the balance of the soft tissuesis not altered thus reducing the chance of relapse Theresults of this study are therefore highly useful for clinicianswho must assess the stability of these structures in patientswho are candidates for orthognathic or orthopedic surgerywhich may help to prevent the obstruction of the upperairway In addition this study helps to identify cephalometricnorms that exist amongmales and females who have differentskeletal sagittal anomalies

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] A G Brodie ldquoEmerging concepts of facial growthrdquo AngleOrthodontist vol 41 no 2 pp 103ndash118 1971

[2] D K Bailey ldquoThenormal cervical spine in infants and childrenrdquoRadiology vol 59 no 5 pp 712ndash719 1952

[3] S W Gray C B Romanie and J E Skandalakis ldquoCongenitalfusion of the cervical vertebraerdquo Surgery Gynecology amp Obstet-rics vol 118 pp 373ndash385 1964

[4] J Huggare ldquoAssociation between morphology of the firstcervical vertebra head posture and craniofacial structuresrdquoEuropean Journal of Orthodontics vol 13 no 6 pp 435ndash4401991

[5] M Sandikcioglu S Skov and B Solow ldquoAtlas morphologyin relation to craniofacial morphology and head posturerdquoEuropean Journal ofOrthodontics vol 16 no 2 pp 96ndash103 1994

[6] E Hellsing J McWilliam T Reigo and E Spangfort ldquoTherelationship between craniofacial morphology head postureand spinal curvature in 8 11 and 15-year-old childrenrdquo EuropeanJournal of Orthodontics vol 9 no 4 pp 254ndash264 1987

[7] J Huggare ldquoA cross-sectional study of head posture andcraniofacial growth in children from the north of Finlandrdquo

Proceedings of the Finnish Dental Society vol 83 no 1 pp 5ndash15 1987

[8] J Huggare and P Houghton ldquoAssociations between atlantoaxialand craniomandibular anatomyrdquo Growth Development andAging vol 60 no 1 pp 21ndash30 1996

[9] A Wenzel E Hojensgaard and J M Henriksen ldquoCraniofacialmorphology and head posture in children with asthma andperennial rhinitisrdquo European Journal of Orthodontics vol 7 no2 pp 83ndash92 1985

[10] L Sonnesen M Bakke and B Solow ldquoTemporomandibulardisorders in relation to craniofacial dimensions head postureand bite force in children selected for orthodontic treatmentrdquoEuropean Journal of Orthodontics vol 23 no 2 pp 179ndash1922001

[11] C M Visscher W De Boer F Lobbezoo L L M H HabetsandMNaeije ldquoIs there a relationship between head posture andcraniomandibular painrdquo Journal of Oral Rehabilitation vol 29no 11 pp 1030ndash1036 2002

[12] H Treuenfels ldquoDie Relation von Atlasposition prognather undprogener Kieferanomalierdquo Fortschritte der Kieferorthopadie vol43 no 1 p 82 1982

[13] U Gustavsson G Hansson A Holmqvist and M LundbergldquoHyoid bone position in relation to head posturerdquo SwedishDental Journal vol 65 no 8 pp 423ndash430 1972

[14] J W Pim Valk A J J Zonnenberg C J van Maanen and OG T van Wonderen ldquoThe biomechanical effects of a sagittalsplit ramus osteotomy on the relationship of the mandible thehyoid bone and the cervical spinerdquo The American Journal ofOrthodontics and Dentofacial Orthopedics vol 102 no 2 pp99ndash108 1992

[15] A Tallgren and B Solow ldquoHyoid bone position facial mor-phology and head posture in adultsrdquo European Journal ofOrthodontics vol 9 no 1 pp 1ndash8 1987

[16] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo AmericanJournal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[17] G J Romanes Cunninghamrsquos Manual of Practical Anatomy vol3 Oxford University Press New York NY USA 14th edition1983

[18] L W Graber ldquoHyoid changes following orthopedic treatmentof mandibular prognathismrdquo Angle Orthodontist vol 48 no 1pp 33ndash38 1978

[19] KMHiiemae SMHayenga andA Reese ldquoPatterns of tongueand jawmovement in a cinefluorographic study of feeding in themacaquerdquo Archives of Oral Biology vol 40 no 3 pp 229ndash2461995

[20] J Spiro J K Rendell and T Gay ldquoActivation and coordinationpatterns of the suprahyoid muscles during swallowingrdquo Laryn-goscope vol 104 no 11 I pp 1376ndash1382 1994

[21] H Tsai ldquoThe positional changes of hyoid bone in childrenrdquoTheJournal of Clinical Pediatric Dentistry vol 27 no 1 pp 29ndash342002

[22] B Fromm and M Lundberg ldquoPostural behaviour of the hyoidbone in normal occlusion and before and after surgical correc-tion of mandibular protrusionrdquo Swedish Dental Journal vol 63no 6 pp 425ndash433 1970

[23] H Opdebeeck W H Bell J Eisenfeld and D MishelevichldquoComparative study between the SFS and LFS rotation as apossible morphogenic mechanismrdquo The American Journal ofOrthodontics vol 74 no 5 pp 509ndash521 1978

8 The Scientific World Journal

[24] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in Class I and Class III malocclusionsrdquo Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol101 no 4 pp 308ndash312 1992

[25] S Carlsoo and G Leijon ldquoA radiographic study of the positionof the hyo-Iaryngeal complex in relation to the skull and thecervical column in manrdquo Transactions Royal Schools DentistryStockholm and Umeft vol 5 pp 13ndash34 1960

[26] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo TheAmerican Journal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[27] K J Showfety P S Vig and S Matteson ldquoA simple method fortaking natural-head-position cephalogramsrdquo American Journalof Orthodontics vol 83 no 6 pp 495ndash500 1983

[28] C C Steiner ldquoCephalometrics for you and merdquo The AmericanJournal of Orthodontics vol 39 no 10 pp 729ndash755 1953

[29] C C Steiner ldquoCephalometrics in clinical practicerdquo The AngleOrthodontist vol 29 no 1 pp 8ndash29 1959

[30] C C Steiner ldquoThe use of cephalometrics as an aid to planningand assessing orthodontic treatment Report of a caserdquo TheAmerican Journal of Orthodontics vol 46 no 10 pp 721ndash7351960

[31] I Ceylan ldquoFarklı Iskelet yapılarında dik yon kranyo-fasiyalmorfoloji hyoid kemigin konumu ve birinci servikal verte-branın morfolojisinin incelenmesirdquo Turk Ortodonti Dernegivol 8 no 1 pp 20ndash29 1995

[32] A G Brodie ldquoAnatomy and physiology of head and neckmusculaturerdquoTheAmerican Journal of Orthodontics vol 36 no11 pp 831ndash844 1950

[33] E Atik and I Kocadereli ldquoCraniofacial morphology head pos-ture and hyoid bone positionrdquo Turkish Journal of Orthodonticsvol 24 no 3 pp 237ndash246 2011

[34] J A Ogden ldquoRadiology of postnatal skeletal development XIThe first cervical vertebrardquo Skeletal Radiology vol 12 no 1 pp12ndash20 1984

[35] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in class I and class III malocclusionsrdquo TheAmerican Journal of Orthodontics and Dentofacial Orthopedicsvol 101 no 4 pp 308ndash312 1992

[36] B Solow S Siersbaek-Nielsen and E Greve ldquoAirway adequacyhead posture and craniofacial morphologyrdquo American Journalof Orthodontics vol 86 no 3 pp 214ndash223 1984

[37] S Valenzuela R Miralles M J Ravera et al ldquoDoes headposture have a significant effect on the hyoid bone positionand sternocleidomastoid electromyographic activity in youngadultsrdquo Journal of Craniomandibular Practice vol 23 no 3 pp204ndash211 2005

[38] R Surucu S Aras and A Soytarhan ldquoCephalometric evalua-tion of the immediate changes in cervical structures after theapplication of the activatorrdquo Turkish Journal of Orthodonticsvol 3 no 2 pp 44ndash49 1990

[39] N EggenspergerW Smolka and T Iizuka ldquoLong-term changesof hyoid bone position and pharyngeal airway size followingmandibular setback by sagittal split ramus osteotomyrdquo Journalof Cranio-Maxillofacial Surgery vol 33 no 2 pp 111ndash117 2005

[40] G Marsan E Oztas N Cura S Vasfi Kuvat and U EmeklildquoChanges in head posture and hyoid bone position in Turkishclass III patients after mandibular setback surgeryrdquo Journal ofCranio-Maxillofacial Surgery vol 38 no 2 pp 113ndash121 2010

[41] A Gale P V J Kilpelainen andM T Laine-Alava ldquoHyoid boneposition after surgical mandibular advancementrdquo EuropeanJournal of Orthodontics vol 23 no 6 pp 695ndash701 2001

[42] B Solow and A Tallgren ldquoHead posture and craniofacialmorphologyrdquo The American Journal of Physical Anthropologyvol 44 no 3 pp 417ndash435 1976

[43] N B Haralabakis NM Toutountzakis and S C Yiagtzis ldquoThehyoid bone position in adult individuals with open bite andnormal occlusionrdquoEuropean Journal of Orthodontics vol 15 no4 pp 265ndash271 1993

[44] I Ceylan and H Oktay ldquoA study on the pharyngeal size in dif-ferent skeletal patternsrdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 108 no 1 pp 69ndash75 1995

[45] Y H Kim and J J Vietas ldquoAnteroposterior dysplasia indicatoran adjunct to cephalometric differential diagnosisrdquoThe Ameri-can Journal of Orthodontics vol 73 no 6 pp 619ndash633 1978

[46] W Hussels and R S Nanda ldquoAnalysis of factors affecting angleANBrdquo American Journal of Orthodontics vol 85 no 5 pp 411ndash423 1984

[47] H Oktay ldquoA comparison of ANBWits AF-BF and APDI mea-surementsrdquo American Journal of Orthodontics and DentofacialOrthopedics vol 104 no 2 pp 584ndash591 1991

[48] M M Ozbek and A Koklu ldquoNatural cervical inclination andcraniofacial structurerdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 104 no 6 pp 584ndash591 1993

[49] H Fjellvang and B Solow ldquoCraniocervical postural relationsand craniofacial morphology in 30 blind subjectsrdquo The Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol90 no 4 pp 327ndash334 1986

[50] A M Sahin Saglam and N E Uydas ldquoRelationship betweenhead posture and hyoid position in adult females and malesrdquoJournal of Cranio-Maxillofacial Surgery vol 34 no 2 pp 85ndash92 2006

[51] I Ceylan Degisik ANB Acılarında Dogal BasKonumu ve HyoidKemiginin Konumunun Incelenmesi Ataturk Universitesi SaglıkBilimleri Enstitusu Ortodonti Anabilim Dalı 1990

[52] B Dincer A Erdinc G Oncag and S Dogan ldquoThe investiga-tion of the hyoid bone position in class 1 class 2 division 1 andclass 3 malocclusionrdquo Turkish Journal of Orthodontics vol 13pp 108ndash115 2000

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral OncologyJournal of

DentistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Case Reports in Dentistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral ImplantsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anesthesiology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Radiology Research and Practice

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Dental SurgeryJournal of

Drug DeliveryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral DiseasesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PainResearch and TreatmentHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Preventive MedicineAdvances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OrthopedicsAdvances in

Page 6: Research Article Cephalometric Investigation of First Cervical Vertebrae Morphology ...downloads.hindawi.com/journals/tswj/2014/159784.pdf ·  · 2015-11-22Research Article Cephalometric

6 The Scientific World Journal

and inferiorly at 3 years after treatment Surucu et al [38]examined 10 individuals with skeletal Class II division Imalocclusions and found that after the activator was appliedand the bite was opened the tongue shifted posteriorly andcaused constriction of the upper airway To compensate forthis constriction patients would need to alter their normalupright head posture by extending the headjawThe authorsreported that as a result of these changes the mandiblemoved into a more anterior position while the hyoid shiftedanteriorly depending on the degree of head extension It hasbeen reported that the hyoidmoves posteriorly and inferiorlyin mandibular setback surgeries [39 40] This subsequentlyresults in the base of the tongue shifting posteriorly andinferiorly resulting in constriction of the upper airway andforcing the patient to further extend the head positionto lengthen the upper airway Posterior movement of themandible can cause relaxation of the suprahyoidmusculaturewhich may instigate balance disorders in the head and neckmuscles and oropharyngeal complex It has been postulatedthat if this relaxation continues for an extended period it canalter the position of the hyoid as well as the length of thesuprahyoid muscle causing skeletal relapse [41]

Cephalometric radiography one of the most importanttools in orthodontics both clinically and in research permitsthe accurate evaluation of the dental skeletal and soft tissuerelationships of the craniofacial complex before the initiationof treatment and during growth [42ndash44]

In light of this information the aim of this study wasto document the position of the hyoid bone and cervicalatlas morphology on the cephalometric radiographs of par-ticipants with different sagittal skeletal patterns with the goalof identifying cephalometric norms To achieve this partic-ipants were classified according to horizontal discrepanciesobserved in the ANB angle a parameter that is widely usedin the evaluation of skeletal anterior-posterior relationships[45ndash47] Previous studies have shown that natural headposture is related to respiratory [48] and visual function[49] Therefore to determine natural head posture in aprecise manner only individuals without visual hearing orrespiratory disturbances were included in this study

Our results from the intragroup comparison of Class Iand Class II participants revealed that several measurementswere significantly larger in males than in females Theseincluded Hy-NSL (119875 lt 0001) Hy-PD (119875 = 0001) andHy-CVT (119875 lt 0001) In addition the hyoid was positionedmore anteriorly and inferiorly in males than in femalesSahin Saglam and Uydas [50] investigated variation in hyoidposition and head posture between genders (38 females and38 males) using lateral cephalometric films obtained using anatural head position All participants had a Class I skeletalpattern and ideal dental occlusion The authors found thatnatural head position did not differ between genders but thehyoid bone was positioned more superiorly and posteriorlyin females compared to males Ceylan [51] examined 90adolescents including 45 boys and 45 girls aged 13ndash15 yearsand analyzed the relationship of the ANB angle and naturalhead position to the position of the hyoid bone Naturalhead position was not significantly affected by gender butthe hyoid bone was positioned significantly more superiorly

and posteriorly in females than in males These results areconsistent with the data reported here

In the intragroup comparison of Class I participantssignificant differences were observed with respect to the 119883119884 Lum and a-p parameters all of which were smaller infemales The data also revealed a greater superior-posteriorarea of C1 shorter distance between C1 and C2 shorteranterior-posterior dimensions and shorter distance betweenthe anterior border of the C1 dorsal arch and the posteriorborder of the C2 odontoid process also in females Theseresults suggest that the male body is more developed than thefemale body

In the intragroup comparison of Class III participantsit was found that the hyoid bone was positioned moreanteriorly and inferiorly in males than in females Cervicaland craniocervical posture may be one factor explaining thesignificant differences observed between males and femaleswho have Class III malocclusions [24] Females who haveClass III malocclusions show amuchmore ldquonormalrdquo positionof the hyoid bone as compared to males with Class IIImalocclusions This may be due to heightened aestheticawareness of a prognathic mandible in girls which leadsthem to assume quite early in life a modified head postureallowing them to minimize the appearance of a prominentchin

Intergroup comparisons of differences between gendersshowed statistically significant differences in ANB measure-ments in all groups These results are unsurprising giventhat participants with normal vertical patterns and differentANB values were included in this study In the intergroupcomparison of males the Hy-CVT distance was found to begreater in Class I than in Class II participants This indicatespronounced anterior positioning of the hyoid bone in Class Imales On the other hand Ceylan [31] evaluated the hyoidbone position in different skeletal patterns of adolescentsaged 13ndash15 years and reported that the hyoid bone waspositionedmore anteriorlywith an increase in theANBangleThis is in direct contrast to our study whichmay be the resultof examining different age groups (adolescents versus youngadults) and the inclusion of participants with normal verticalskeletal patterns in our work Dincer et al [52] investigatedthe position of the hyoid bone with respect to its relationshipwith the dentofacial system in 45 participants with ClassI Class II division I and Class III malocclusions It wasascertained that the hyoid was positioned more posteriorlyamong participants with a Class II division I skeletal patterncompared to a Class I pattern and more anteriorly amongparticipants with a Class III skeletal pattern compared toa Class I pattern In addition the greater 119883 values amongClass I versus Class III participants indicate an overall lowerposition of C1 in the Class I group Class III participants hadhigher 119885 values compared to the Class II group accordinglythe distance between the posterior part of C1 andC2 is greaterin Class III versus Class II participants

Regarding skeletal patterns in female participants no dif-ference was observed for parameters relating to the hyoid orC1 indicating nomorphological difference in these structuresamong females Consistent with our findings Adamidis andSpyropoulos [24] found no statistically significant differences

The Scientific World Journal 7

in the position or orientation of the hyoid among femalesexhibiting Class I malocclusions versus those with Class IIImalocclusions

5 Conclusions

This study revealed that the hyoid bone is positioned moreinferiorly and anteriorly and is more prominent in malesthan in females regardless of variation in the axial skeletonC1 was also larger along the anterior-posterior axis in malesexhibiting a Class I skeletal pattern compared to females inthe same class However no significant difference in hyoidposition or C1 morphology was observed in relation to theANB in females In the sagittal plane the hyoid bone wassimilar in males with a Class I or Class III skeletal patternbut was positioned more posteriorly based on mandibularbone development in males with Class I skeletal patterns Inaddition the vertical position of C1 varied depending on thesagittal skeletal pattern among male participants

It is especially important among males that the hyoidbone remains in the same position after orthodontic andorthognathic treatment so that the balance of the soft tissuesis not altered thus reducing the chance of relapse Theresults of this study are therefore highly useful for clinicianswho must assess the stability of these structures in patientswho are candidates for orthognathic or orthopedic surgerywhich may help to prevent the obstruction of the upperairway In addition this study helps to identify cephalometricnorms that exist amongmales and females who have differentskeletal sagittal anomalies

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] A G Brodie ldquoEmerging concepts of facial growthrdquo AngleOrthodontist vol 41 no 2 pp 103ndash118 1971

[2] D K Bailey ldquoThenormal cervical spine in infants and childrenrdquoRadiology vol 59 no 5 pp 712ndash719 1952

[3] S W Gray C B Romanie and J E Skandalakis ldquoCongenitalfusion of the cervical vertebraerdquo Surgery Gynecology amp Obstet-rics vol 118 pp 373ndash385 1964

[4] J Huggare ldquoAssociation between morphology of the firstcervical vertebra head posture and craniofacial structuresrdquoEuropean Journal of Orthodontics vol 13 no 6 pp 435ndash4401991

[5] M Sandikcioglu S Skov and B Solow ldquoAtlas morphologyin relation to craniofacial morphology and head posturerdquoEuropean Journal ofOrthodontics vol 16 no 2 pp 96ndash103 1994

[6] E Hellsing J McWilliam T Reigo and E Spangfort ldquoTherelationship between craniofacial morphology head postureand spinal curvature in 8 11 and 15-year-old childrenrdquo EuropeanJournal of Orthodontics vol 9 no 4 pp 254ndash264 1987

[7] J Huggare ldquoA cross-sectional study of head posture andcraniofacial growth in children from the north of Finlandrdquo

Proceedings of the Finnish Dental Society vol 83 no 1 pp 5ndash15 1987

[8] J Huggare and P Houghton ldquoAssociations between atlantoaxialand craniomandibular anatomyrdquo Growth Development andAging vol 60 no 1 pp 21ndash30 1996

[9] A Wenzel E Hojensgaard and J M Henriksen ldquoCraniofacialmorphology and head posture in children with asthma andperennial rhinitisrdquo European Journal of Orthodontics vol 7 no2 pp 83ndash92 1985

[10] L Sonnesen M Bakke and B Solow ldquoTemporomandibulardisorders in relation to craniofacial dimensions head postureand bite force in children selected for orthodontic treatmentrdquoEuropean Journal of Orthodontics vol 23 no 2 pp 179ndash1922001

[11] C M Visscher W De Boer F Lobbezoo L L M H HabetsandMNaeije ldquoIs there a relationship between head posture andcraniomandibular painrdquo Journal of Oral Rehabilitation vol 29no 11 pp 1030ndash1036 2002

[12] H Treuenfels ldquoDie Relation von Atlasposition prognather undprogener Kieferanomalierdquo Fortschritte der Kieferorthopadie vol43 no 1 p 82 1982

[13] U Gustavsson G Hansson A Holmqvist and M LundbergldquoHyoid bone position in relation to head posturerdquo SwedishDental Journal vol 65 no 8 pp 423ndash430 1972

[14] J W Pim Valk A J J Zonnenberg C J van Maanen and OG T van Wonderen ldquoThe biomechanical effects of a sagittalsplit ramus osteotomy on the relationship of the mandible thehyoid bone and the cervical spinerdquo The American Journal ofOrthodontics and Dentofacial Orthopedics vol 102 no 2 pp99ndash108 1992

[15] A Tallgren and B Solow ldquoHyoid bone position facial mor-phology and head posture in adultsrdquo European Journal ofOrthodontics vol 9 no 1 pp 1ndash8 1987

[16] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo AmericanJournal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[17] G J Romanes Cunninghamrsquos Manual of Practical Anatomy vol3 Oxford University Press New York NY USA 14th edition1983

[18] L W Graber ldquoHyoid changes following orthopedic treatmentof mandibular prognathismrdquo Angle Orthodontist vol 48 no 1pp 33ndash38 1978

[19] KMHiiemae SMHayenga andA Reese ldquoPatterns of tongueand jawmovement in a cinefluorographic study of feeding in themacaquerdquo Archives of Oral Biology vol 40 no 3 pp 229ndash2461995

[20] J Spiro J K Rendell and T Gay ldquoActivation and coordinationpatterns of the suprahyoid muscles during swallowingrdquo Laryn-goscope vol 104 no 11 I pp 1376ndash1382 1994

[21] H Tsai ldquoThe positional changes of hyoid bone in childrenrdquoTheJournal of Clinical Pediatric Dentistry vol 27 no 1 pp 29ndash342002

[22] B Fromm and M Lundberg ldquoPostural behaviour of the hyoidbone in normal occlusion and before and after surgical correc-tion of mandibular protrusionrdquo Swedish Dental Journal vol 63no 6 pp 425ndash433 1970

[23] H Opdebeeck W H Bell J Eisenfeld and D MishelevichldquoComparative study between the SFS and LFS rotation as apossible morphogenic mechanismrdquo The American Journal ofOrthodontics vol 74 no 5 pp 509ndash521 1978

8 The Scientific World Journal

[24] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in Class I and Class III malocclusionsrdquo Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol101 no 4 pp 308ndash312 1992

[25] S Carlsoo and G Leijon ldquoA radiographic study of the positionof the hyo-Iaryngeal complex in relation to the skull and thecervical column in manrdquo Transactions Royal Schools DentistryStockholm and Umeft vol 5 pp 13ndash34 1960

[26] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo TheAmerican Journal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[27] K J Showfety P S Vig and S Matteson ldquoA simple method fortaking natural-head-position cephalogramsrdquo American Journalof Orthodontics vol 83 no 6 pp 495ndash500 1983

[28] C C Steiner ldquoCephalometrics for you and merdquo The AmericanJournal of Orthodontics vol 39 no 10 pp 729ndash755 1953

[29] C C Steiner ldquoCephalometrics in clinical practicerdquo The AngleOrthodontist vol 29 no 1 pp 8ndash29 1959

[30] C C Steiner ldquoThe use of cephalometrics as an aid to planningand assessing orthodontic treatment Report of a caserdquo TheAmerican Journal of Orthodontics vol 46 no 10 pp 721ndash7351960

[31] I Ceylan ldquoFarklı Iskelet yapılarında dik yon kranyo-fasiyalmorfoloji hyoid kemigin konumu ve birinci servikal verte-branın morfolojisinin incelenmesirdquo Turk Ortodonti Dernegivol 8 no 1 pp 20ndash29 1995

[32] A G Brodie ldquoAnatomy and physiology of head and neckmusculaturerdquoTheAmerican Journal of Orthodontics vol 36 no11 pp 831ndash844 1950

[33] E Atik and I Kocadereli ldquoCraniofacial morphology head pos-ture and hyoid bone positionrdquo Turkish Journal of Orthodonticsvol 24 no 3 pp 237ndash246 2011

[34] J A Ogden ldquoRadiology of postnatal skeletal development XIThe first cervical vertebrardquo Skeletal Radiology vol 12 no 1 pp12ndash20 1984

[35] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in class I and class III malocclusionsrdquo TheAmerican Journal of Orthodontics and Dentofacial Orthopedicsvol 101 no 4 pp 308ndash312 1992

[36] B Solow S Siersbaek-Nielsen and E Greve ldquoAirway adequacyhead posture and craniofacial morphologyrdquo American Journalof Orthodontics vol 86 no 3 pp 214ndash223 1984

[37] S Valenzuela R Miralles M J Ravera et al ldquoDoes headposture have a significant effect on the hyoid bone positionand sternocleidomastoid electromyographic activity in youngadultsrdquo Journal of Craniomandibular Practice vol 23 no 3 pp204ndash211 2005

[38] R Surucu S Aras and A Soytarhan ldquoCephalometric evalua-tion of the immediate changes in cervical structures after theapplication of the activatorrdquo Turkish Journal of Orthodonticsvol 3 no 2 pp 44ndash49 1990

[39] N EggenspergerW Smolka and T Iizuka ldquoLong-term changesof hyoid bone position and pharyngeal airway size followingmandibular setback by sagittal split ramus osteotomyrdquo Journalof Cranio-Maxillofacial Surgery vol 33 no 2 pp 111ndash117 2005

[40] G Marsan E Oztas N Cura S Vasfi Kuvat and U EmeklildquoChanges in head posture and hyoid bone position in Turkishclass III patients after mandibular setback surgeryrdquo Journal ofCranio-Maxillofacial Surgery vol 38 no 2 pp 113ndash121 2010

[41] A Gale P V J Kilpelainen andM T Laine-Alava ldquoHyoid boneposition after surgical mandibular advancementrdquo EuropeanJournal of Orthodontics vol 23 no 6 pp 695ndash701 2001

[42] B Solow and A Tallgren ldquoHead posture and craniofacialmorphologyrdquo The American Journal of Physical Anthropologyvol 44 no 3 pp 417ndash435 1976

[43] N B Haralabakis NM Toutountzakis and S C Yiagtzis ldquoThehyoid bone position in adult individuals with open bite andnormal occlusionrdquoEuropean Journal of Orthodontics vol 15 no4 pp 265ndash271 1993

[44] I Ceylan and H Oktay ldquoA study on the pharyngeal size in dif-ferent skeletal patternsrdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 108 no 1 pp 69ndash75 1995

[45] Y H Kim and J J Vietas ldquoAnteroposterior dysplasia indicatoran adjunct to cephalometric differential diagnosisrdquoThe Ameri-can Journal of Orthodontics vol 73 no 6 pp 619ndash633 1978

[46] W Hussels and R S Nanda ldquoAnalysis of factors affecting angleANBrdquo American Journal of Orthodontics vol 85 no 5 pp 411ndash423 1984

[47] H Oktay ldquoA comparison of ANBWits AF-BF and APDI mea-surementsrdquo American Journal of Orthodontics and DentofacialOrthopedics vol 104 no 2 pp 584ndash591 1991

[48] M M Ozbek and A Koklu ldquoNatural cervical inclination andcraniofacial structurerdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 104 no 6 pp 584ndash591 1993

[49] H Fjellvang and B Solow ldquoCraniocervical postural relationsand craniofacial morphology in 30 blind subjectsrdquo The Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol90 no 4 pp 327ndash334 1986

[50] A M Sahin Saglam and N E Uydas ldquoRelationship betweenhead posture and hyoid position in adult females and malesrdquoJournal of Cranio-Maxillofacial Surgery vol 34 no 2 pp 85ndash92 2006

[51] I Ceylan Degisik ANB Acılarında Dogal BasKonumu ve HyoidKemiginin Konumunun Incelenmesi Ataturk Universitesi SaglıkBilimleri Enstitusu Ortodonti Anabilim Dalı 1990

[52] B Dincer A Erdinc G Oncag and S Dogan ldquoThe investiga-tion of the hyoid bone position in class 1 class 2 division 1 andclass 3 malocclusionrdquo Turkish Journal of Orthodontics vol 13pp 108ndash115 2000

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral OncologyJournal of

DentistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Case Reports in Dentistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral ImplantsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anesthesiology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Radiology Research and Practice

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Dental SurgeryJournal of

Drug DeliveryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral DiseasesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PainResearch and TreatmentHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Preventive MedicineAdvances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OrthopedicsAdvances in

Page 7: Research Article Cephalometric Investigation of First Cervical Vertebrae Morphology ...downloads.hindawi.com/journals/tswj/2014/159784.pdf ·  · 2015-11-22Research Article Cephalometric

The Scientific World Journal 7

in the position or orientation of the hyoid among femalesexhibiting Class I malocclusions versus those with Class IIImalocclusions

5 Conclusions

This study revealed that the hyoid bone is positioned moreinferiorly and anteriorly and is more prominent in malesthan in females regardless of variation in the axial skeletonC1 was also larger along the anterior-posterior axis in malesexhibiting a Class I skeletal pattern compared to females inthe same class However no significant difference in hyoidposition or C1 morphology was observed in relation to theANB in females In the sagittal plane the hyoid bone wassimilar in males with a Class I or Class III skeletal patternbut was positioned more posteriorly based on mandibularbone development in males with Class I skeletal patterns Inaddition the vertical position of C1 varied depending on thesagittal skeletal pattern among male participants

It is especially important among males that the hyoidbone remains in the same position after orthodontic andorthognathic treatment so that the balance of the soft tissuesis not altered thus reducing the chance of relapse Theresults of this study are therefore highly useful for clinicianswho must assess the stability of these structures in patientswho are candidates for orthognathic or orthopedic surgerywhich may help to prevent the obstruction of the upperairway In addition this study helps to identify cephalometricnorms that exist amongmales and females who have differentskeletal sagittal anomalies

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] A G Brodie ldquoEmerging concepts of facial growthrdquo AngleOrthodontist vol 41 no 2 pp 103ndash118 1971

[2] D K Bailey ldquoThenormal cervical spine in infants and childrenrdquoRadiology vol 59 no 5 pp 712ndash719 1952

[3] S W Gray C B Romanie and J E Skandalakis ldquoCongenitalfusion of the cervical vertebraerdquo Surgery Gynecology amp Obstet-rics vol 118 pp 373ndash385 1964

[4] J Huggare ldquoAssociation between morphology of the firstcervical vertebra head posture and craniofacial structuresrdquoEuropean Journal of Orthodontics vol 13 no 6 pp 435ndash4401991

[5] M Sandikcioglu S Skov and B Solow ldquoAtlas morphologyin relation to craniofacial morphology and head posturerdquoEuropean Journal ofOrthodontics vol 16 no 2 pp 96ndash103 1994

[6] E Hellsing J McWilliam T Reigo and E Spangfort ldquoTherelationship between craniofacial morphology head postureand spinal curvature in 8 11 and 15-year-old childrenrdquo EuropeanJournal of Orthodontics vol 9 no 4 pp 254ndash264 1987

[7] J Huggare ldquoA cross-sectional study of head posture andcraniofacial growth in children from the north of Finlandrdquo

Proceedings of the Finnish Dental Society vol 83 no 1 pp 5ndash15 1987

[8] J Huggare and P Houghton ldquoAssociations between atlantoaxialand craniomandibular anatomyrdquo Growth Development andAging vol 60 no 1 pp 21ndash30 1996

[9] A Wenzel E Hojensgaard and J M Henriksen ldquoCraniofacialmorphology and head posture in children with asthma andperennial rhinitisrdquo European Journal of Orthodontics vol 7 no2 pp 83ndash92 1985

[10] L Sonnesen M Bakke and B Solow ldquoTemporomandibulardisorders in relation to craniofacial dimensions head postureand bite force in children selected for orthodontic treatmentrdquoEuropean Journal of Orthodontics vol 23 no 2 pp 179ndash1922001

[11] C M Visscher W De Boer F Lobbezoo L L M H HabetsandMNaeije ldquoIs there a relationship between head posture andcraniomandibular painrdquo Journal of Oral Rehabilitation vol 29no 11 pp 1030ndash1036 2002

[12] H Treuenfels ldquoDie Relation von Atlasposition prognather undprogener Kieferanomalierdquo Fortschritte der Kieferorthopadie vol43 no 1 p 82 1982

[13] U Gustavsson G Hansson A Holmqvist and M LundbergldquoHyoid bone position in relation to head posturerdquo SwedishDental Journal vol 65 no 8 pp 423ndash430 1972

[14] J W Pim Valk A J J Zonnenberg C J van Maanen and OG T van Wonderen ldquoThe biomechanical effects of a sagittalsplit ramus osteotomy on the relationship of the mandible thehyoid bone and the cervical spinerdquo The American Journal ofOrthodontics and Dentofacial Orthopedics vol 102 no 2 pp99ndash108 1992

[15] A Tallgren and B Solow ldquoHyoid bone position facial mor-phology and head posture in adultsrdquo European Journal ofOrthodontics vol 9 no 1 pp 1ndash8 1987

[16] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo AmericanJournal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[17] G J Romanes Cunninghamrsquos Manual of Practical Anatomy vol3 Oxford University Press New York NY USA 14th edition1983

[18] L W Graber ldquoHyoid changes following orthopedic treatmentof mandibular prognathismrdquo Angle Orthodontist vol 48 no 1pp 33ndash38 1978

[19] KMHiiemae SMHayenga andA Reese ldquoPatterns of tongueand jawmovement in a cinefluorographic study of feeding in themacaquerdquo Archives of Oral Biology vol 40 no 3 pp 229ndash2461995

[20] J Spiro J K Rendell and T Gay ldquoActivation and coordinationpatterns of the suprahyoid muscles during swallowingrdquo Laryn-goscope vol 104 no 11 I pp 1376ndash1382 1994

[21] H Tsai ldquoThe positional changes of hyoid bone in childrenrdquoTheJournal of Clinical Pediatric Dentistry vol 27 no 1 pp 29ndash342002

[22] B Fromm and M Lundberg ldquoPostural behaviour of the hyoidbone in normal occlusion and before and after surgical correc-tion of mandibular protrusionrdquo Swedish Dental Journal vol 63no 6 pp 425ndash433 1970

[23] H Opdebeeck W H Bell J Eisenfeld and D MishelevichldquoComparative study between the SFS and LFS rotation as apossible morphogenic mechanismrdquo The American Journal ofOrthodontics vol 74 no 5 pp 509ndash521 1978

8 The Scientific World Journal

[24] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in Class I and Class III malocclusionsrdquo Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol101 no 4 pp 308ndash312 1992

[25] S Carlsoo and G Leijon ldquoA radiographic study of the positionof the hyo-Iaryngeal complex in relation to the skull and thecervical column in manrdquo Transactions Royal Schools DentistryStockholm and Umeft vol 5 pp 13ndash34 1960

[26] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo TheAmerican Journal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[27] K J Showfety P S Vig and S Matteson ldquoA simple method fortaking natural-head-position cephalogramsrdquo American Journalof Orthodontics vol 83 no 6 pp 495ndash500 1983

[28] C C Steiner ldquoCephalometrics for you and merdquo The AmericanJournal of Orthodontics vol 39 no 10 pp 729ndash755 1953

[29] C C Steiner ldquoCephalometrics in clinical practicerdquo The AngleOrthodontist vol 29 no 1 pp 8ndash29 1959

[30] C C Steiner ldquoThe use of cephalometrics as an aid to planningand assessing orthodontic treatment Report of a caserdquo TheAmerican Journal of Orthodontics vol 46 no 10 pp 721ndash7351960

[31] I Ceylan ldquoFarklı Iskelet yapılarında dik yon kranyo-fasiyalmorfoloji hyoid kemigin konumu ve birinci servikal verte-branın morfolojisinin incelenmesirdquo Turk Ortodonti Dernegivol 8 no 1 pp 20ndash29 1995

[32] A G Brodie ldquoAnatomy and physiology of head and neckmusculaturerdquoTheAmerican Journal of Orthodontics vol 36 no11 pp 831ndash844 1950

[33] E Atik and I Kocadereli ldquoCraniofacial morphology head pos-ture and hyoid bone positionrdquo Turkish Journal of Orthodonticsvol 24 no 3 pp 237ndash246 2011

[34] J A Ogden ldquoRadiology of postnatal skeletal development XIThe first cervical vertebrardquo Skeletal Radiology vol 12 no 1 pp12ndash20 1984

[35] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in class I and class III malocclusionsrdquo TheAmerican Journal of Orthodontics and Dentofacial Orthopedicsvol 101 no 4 pp 308ndash312 1992

[36] B Solow S Siersbaek-Nielsen and E Greve ldquoAirway adequacyhead posture and craniofacial morphologyrdquo American Journalof Orthodontics vol 86 no 3 pp 214ndash223 1984

[37] S Valenzuela R Miralles M J Ravera et al ldquoDoes headposture have a significant effect on the hyoid bone positionand sternocleidomastoid electromyographic activity in youngadultsrdquo Journal of Craniomandibular Practice vol 23 no 3 pp204ndash211 2005

[38] R Surucu S Aras and A Soytarhan ldquoCephalometric evalua-tion of the immediate changes in cervical structures after theapplication of the activatorrdquo Turkish Journal of Orthodonticsvol 3 no 2 pp 44ndash49 1990

[39] N EggenspergerW Smolka and T Iizuka ldquoLong-term changesof hyoid bone position and pharyngeal airway size followingmandibular setback by sagittal split ramus osteotomyrdquo Journalof Cranio-Maxillofacial Surgery vol 33 no 2 pp 111ndash117 2005

[40] G Marsan E Oztas N Cura S Vasfi Kuvat and U EmeklildquoChanges in head posture and hyoid bone position in Turkishclass III patients after mandibular setback surgeryrdquo Journal ofCranio-Maxillofacial Surgery vol 38 no 2 pp 113ndash121 2010

[41] A Gale P V J Kilpelainen andM T Laine-Alava ldquoHyoid boneposition after surgical mandibular advancementrdquo EuropeanJournal of Orthodontics vol 23 no 6 pp 695ndash701 2001

[42] B Solow and A Tallgren ldquoHead posture and craniofacialmorphologyrdquo The American Journal of Physical Anthropologyvol 44 no 3 pp 417ndash435 1976

[43] N B Haralabakis NM Toutountzakis and S C Yiagtzis ldquoThehyoid bone position in adult individuals with open bite andnormal occlusionrdquoEuropean Journal of Orthodontics vol 15 no4 pp 265ndash271 1993

[44] I Ceylan and H Oktay ldquoA study on the pharyngeal size in dif-ferent skeletal patternsrdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 108 no 1 pp 69ndash75 1995

[45] Y H Kim and J J Vietas ldquoAnteroposterior dysplasia indicatoran adjunct to cephalometric differential diagnosisrdquoThe Ameri-can Journal of Orthodontics vol 73 no 6 pp 619ndash633 1978

[46] W Hussels and R S Nanda ldquoAnalysis of factors affecting angleANBrdquo American Journal of Orthodontics vol 85 no 5 pp 411ndash423 1984

[47] H Oktay ldquoA comparison of ANBWits AF-BF and APDI mea-surementsrdquo American Journal of Orthodontics and DentofacialOrthopedics vol 104 no 2 pp 584ndash591 1991

[48] M M Ozbek and A Koklu ldquoNatural cervical inclination andcraniofacial structurerdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 104 no 6 pp 584ndash591 1993

[49] H Fjellvang and B Solow ldquoCraniocervical postural relationsand craniofacial morphology in 30 blind subjectsrdquo The Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol90 no 4 pp 327ndash334 1986

[50] A M Sahin Saglam and N E Uydas ldquoRelationship betweenhead posture and hyoid position in adult females and malesrdquoJournal of Cranio-Maxillofacial Surgery vol 34 no 2 pp 85ndash92 2006

[51] I Ceylan Degisik ANB Acılarında Dogal BasKonumu ve HyoidKemiginin Konumunun Incelenmesi Ataturk Universitesi SaglıkBilimleri Enstitusu Ortodonti Anabilim Dalı 1990

[52] B Dincer A Erdinc G Oncag and S Dogan ldquoThe investiga-tion of the hyoid bone position in class 1 class 2 division 1 andclass 3 malocclusionrdquo Turkish Journal of Orthodontics vol 13pp 108ndash115 2000

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral OncologyJournal of

DentistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Case Reports in Dentistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral ImplantsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anesthesiology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Radiology Research and Practice

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Dental SurgeryJournal of

Drug DeliveryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral DiseasesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PainResearch and TreatmentHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Preventive MedicineAdvances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OrthopedicsAdvances in

Page 8: Research Article Cephalometric Investigation of First Cervical Vertebrae Morphology ...downloads.hindawi.com/journals/tswj/2014/159784.pdf ·  · 2015-11-22Research Article Cephalometric

8 The Scientific World Journal

[24] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in Class I and Class III malocclusionsrdquo Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol101 no 4 pp 308ndash312 1992

[25] S Carlsoo and G Leijon ldquoA radiographic study of the positionof the hyo-Iaryngeal complex in relation to the skull and thecervical column in manrdquo Transactions Royal Schools DentistryStockholm and Umeft vol 5 pp 13ndash34 1960

[26] R E Bibby and C B Preston ldquoThe hyoid trianglerdquo TheAmerican Journal of Orthodontics vol 80 no 1 pp 92ndash97 1981

[27] K J Showfety P S Vig and S Matteson ldquoA simple method fortaking natural-head-position cephalogramsrdquo American Journalof Orthodontics vol 83 no 6 pp 495ndash500 1983

[28] C C Steiner ldquoCephalometrics for you and merdquo The AmericanJournal of Orthodontics vol 39 no 10 pp 729ndash755 1953

[29] C C Steiner ldquoCephalometrics in clinical practicerdquo The AngleOrthodontist vol 29 no 1 pp 8ndash29 1959

[30] C C Steiner ldquoThe use of cephalometrics as an aid to planningand assessing orthodontic treatment Report of a caserdquo TheAmerican Journal of Orthodontics vol 46 no 10 pp 721ndash7351960

[31] I Ceylan ldquoFarklı Iskelet yapılarında dik yon kranyo-fasiyalmorfoloji hyoid kemigin konumu ve birinci servikal verte-branın morfolojisinin incelenmesirdquo Turk Ortodonti Dernegivol 8 no 1 pp 20ndash29 1995

[32] A G Brodie ldquoAnatomy and physiology of head and neckmusculaturerdquoTheAmerican Journal of Orthodontics vol 36 no11 pp 831ndash844 1950

[33] E Atik and I Kocadereli ldquoCraniofacial morphology head pos-ture and hyoid bone positionrdquo Turkish Journal of Orthodonticsvol 24 no 3 pp 237ndash246 2011

[34] J A Ogden ldquoRadiology of postnatal skeletal development XIThe first cervical vertebrardquo Skeletal Radiology vol 12 no 1 pp12ndash20 1984

[35] I P Adamidis and M N Spyropoulos ldquoHyoid bone positionand orientation in class I and class III malocclusionsrdquo TheAmerican Journal of Orthodontics and Dentofacial Orthopedicsvol 101 no 4 pp 308ndash312 1992

[36] B Solow S Siersbaek-Nielsen and E Greve ldquoAirway adequacyhead posture and craniofacial morphologyrdquo American Journalof Orthodontics vol 86 no 3 pp 214ndash223 1984

[37] S Valenzuela R Miralles M J Ravera et al ldquoDoes headposture have a significant effect on the hyoid bone positionand sternocleidomastoid electromyographic activity in youngadultsrdquo Journal of Craniomandibular Practice vol 23 no 3 pp204ndash211 2005

[38] R Surucu S Aras and A Soytarhan ldquoCephalometric evalua-tion of the immediate changes in cervical structures after theapplication of the activatorrdquo Turkish Journal of Orthodonticsvol 3 no 2 pp 44ndash49 1990

[39] N EggenspergerW Smolka and T Iizuka ldquoLong-term changesof hyoid bone position and pharyngeal airway size followingmandibular setback by sagittal split ramus osteotomyrdquo Journalof Cranio-Maxillofacial Surgery vol 33 no 2 pp 111ndash117 2005

[40] G Marsan E Oztas N Cura S Vasfi Kuvat and U EmeklildquoChanges in head posture and hyoid bone position in Turkishclass III patients after mandibular setback surgeryrdquo Journal ofCranio-Maxillofacial Surgery vol 38 no 2 pp 113ndash121 2010

[41] A Gale P V J Kilpelainen andM T Laine-Alava ldquoHyoid boneposition after surgical mandibular advancementrdquo EuropeanJournal of Orthodontics vol 23 no 6 pp 695ndash701 2001

[42] B Solow and A Tallgren ldquoHead posture and craniofacialmorphologyrdquo The American Journal of Physical Anthropologyvol 44 no 3 pp 417ndash435 1976

[43] N B Haralabakis NM Toutountzakis and S C Yiagtzis ldquoThehyoid bone position in adult individuals with open bite andnormal occlusionrdquoEuropean Journal of Orthodontics vol 15 no4 pp 265ndash271 1993

[44] I Ceylan and H Oktay ldquoA study on the pharyngeal size in dif-ferent skeletal patternsrdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 108 no 1 pp 69ndash75 1995

[45] Y H Kim and J J Vietas ldquoAnteroposterior dysplasia indicatoran adjunct to cephalometric differential diagnosisrdquoThe Ameri-can Journal of Orthodontics vol 73 no 6 pp 619ndash633 1978

[46] W Hussels and R S Nanda ldquoAnalysis of factors affecting angleANBrdquo American Journal of Orthodontics vol 85 no 5 pp 411ndash423 1984

[47] H Oktay ldquoA comparison of ANBWits AF-BF and APDI mea-surementsrdquo American Journal of Orthodontics and DentofacialOrthopedics vol 104 no 2 pp 584ndash591 1991

[48] M M Ozbek and A Koklu ldquoNatural cervical inclination andcraniofacial structurerdquo The American Journal of Orthodonticsand Dentofacial Orthopedics vol 104 no 6 pp 584ndash591 1993

[49] H Fjellvang and B Solow ldquoCraniocervical postural relationsand craniofacial morphology in 30 blind subjectsrdquo The Amer-ican Journal of Orthodontics and Dentofacial Orthopedics vol90 no 4 pp 327ndash334 1986

[50] A M Sahin Saglam and N E Uydas ldquoRelationship betweenhead posture and hyoid position in adult females and malesrdquoJournal of Cranio-Maxillofacial Surgery vol 34 no 2 pp 85ndash92 2006

[51] I Ceylan Degisik ANB Acılarında Dogal BasKonumu ve HyoidKemiginin Konumunun Incelenmesi Ataturk Universitesi SaglıkBilimleri Enstitusu Ortodonti Anabilim Dalı 1990

[52] B Dincer A Erdinc G Oncag and S Dogan ldquoThe investiga-tion of the hyoid bone position in class 1 class 2 division 1 andclass 3 malocclusionrdquo Turkish Journal of Orthodontics vol 13pp 108ndash115 2000

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral OncologyJournal of

DentistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Case Reports in Dentistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral ImplantsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anesthesiology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Radiology Research and Practice

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Dental SurgeryJournal of

Drug DeliveryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral DiseasesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PainResearch and TreatmentHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Preventive MedicineAdvances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OrthopedicsAdvances in

Page 9: Research Article Cephalometric Investigation of First Cervical Vertebrae Morphology ...downloads.hindawi.com/journals/tswj/2014/159784.pdf ·  · 2015-11-22Research Article Cephalometric

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral OncologyJournal of

DentistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Case Reports in Dentistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral ImplantsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anesthesiology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Radiology Research and Practice

Environmental and Public Health

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Dental SurgeryJournal of

Drug DeliveryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oral DiseasesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PainResearch and TreatmentHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Preventive MedicineAdvances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OrthopedicsAdvances in