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PPsychologic problems and difficulties related tofunction, health, and stability may occur with
anterior open bite. These difficulties may includediminished dental esthetics during speech andwhen smiling, lack of incisal guidance and caninedisclusion resulting in molar cuspal wear, exacerba-tion of temporomandibular dysfunction, lisping andinvoluntary spitting when speaking, posterior cross-bite with functional shift of the mandible related to aposterior collapse of the maxilla, and maxillaryincisor root resorption.1 If relapse of anterior openbite occurs after orthodontic treatment, the afore-mentioned problems may cause patient dissatisfac-tion and possibly result in litigation.
Orthodontists have long recognized that anterioropen bite is difficult to treat and tends to relapseposttreatment.2,3 These malocclusions do exhibitsignificant relapse posttreatment whether the cor-rection was achieved with conventional orthodontictreatment or with orthodontic treatment combinedwith surgery. Lopez-Gavito et al2 reported that more
than 35% of anterior open bite patients treated withconventional orthodontic appliances relapsed 3 mmor more at 10 years postretention. Lopez-Gavito et alconcluded that neither the magnitude of the pre-treatment open bite, the mandibular plane angle,nor any other single parameter of dentofacial formwas a reliable predictor of posttreatment stability orrelapse.
A 20% to 40% relapse of anterior open bite hasbeen reported with maxillary surgical impaction inhyperdivergent patients.3–6 Hyperdivergency is con-sidered the main risk factor for anterior open bitemalocclusion and for its relapse. However, oncehyperdivergency is successfully eliminated withorthognathic surgery it cannot be postulated as anetiologic factor in open bite relapse. This is particu-larly true for adults because they have minimal sub-sequent growth.7 To further complicate matters,some authors8,9 have shown that most individualswith a high-angle malocclusion have a normal over-bite or a deep bite due to a compensatory eruptionmechanism. Thus, skeletal pattern alone is not suffi-cient to identify those patients with an open bite oropen bite tendency.
Joondeph and Riedel,10 citing various authors,explain that open bite malocclusion may be sec-ondary to mouth breathing resulting from nasophar-ynx obstruction. The obstruction could be due toanatomic blockage, allergic disease, or adenoid
CorCorrrection of Antection of Anterior Open Biterior Open Bite e with Spurs: Long-with Spurs: Long-TTererm Sm Stabilitytability
Roberto Justus, DDS, Fis, MSD1
Aim: To show that the high relapse incidence of malocclusion characterized by anterioropen bite is frequently due to an anterior tongue rest posture, an etiologic factor that hasbeen largely overlooked both in conventional orthodontic treatment and in surgical treat-ment. Method: A maxillary fixed intraoral appliance with spurs was used to modify anteriortongue posture. Results: Research with this appliance in a large sample of anterior openbite patients demonstrated long-term stability postretention. Clinical cases using thismethod are presented. Conclusion: In the overall scheme of open bite treatment, therapywith intraoral spurs for the correction of anterior open bite has a wide range of application.World J Orthod 2001;2:219–231.
1Director of Research, Department of Orthodontics, UniversidadIntercontinental. Mexico City, Mexico and Private Practice ofOrthodontics, Mexico City, Mexico.
REPRINT REQUESTS/CORRESPONDENCEDr Roberto Justus, Ave Ejército Nacional 530-502, Mexico DF,Mexico. E-mail: [email protected]
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hyperplasia; or it could be habitual, which wouldnecessitate a compensatory low anterior tongue pos-ture to be able to breathe. Vig11 stresses that moreobjective tests are required and unambiguous crite-ria need to be established if airway impairment is tobe adequately defined and its etiologic significancein relationship to facial growth determined. She con-cludes that only when this issue is resolved will theclinical impact of respiratory function be clarifiedand the appropriate interventions advocated.
PROPOSAL TO MINIMIZE PROPOSAL TO MINIMIZE ANTERIOR OPEN BITE RELAPSEANTERIOR OPEN BITE RELAPSE
The author proposes that anterior tongue rest pos-ture is an etiologic factor that has largely been over-looked both in conventional orthodontic treatmentand in surgical treatment. Failure of tongue postureadaptation subsequent to orthodontic and/or surgi-cal treatment might be the primary reason forrelapse of anterior open bite. Myofunctional therapyis useful for individuals with speech problemsbecause training can modify speech; this is thebasis of “speech therapy.” Speech is constantlymonitored by hearing, which is an important adjunctin modifying this activity. Tongue posture, on theother hand, is not constantly monitored; it is uncon-scious and not easily modified by volition. Sinceanterior tongue rest posture can cause anterior openbite, the author suggests modifying tongue posturewith appliances instead of exercises. The teeth aretogether only 60 to 90 minutes each 24-hour period,so mandibular and tongue rest posture is a domi-nant factor. Delayed deglutitional maturation frominfantile protrusive position to the mature retracted,contained posture can be a factor, according toGraber.12 Nowhere is the Sicher axiom, “Wheneverthere is a struggle between muscle and bone, boneyields,” more true than in open bite malocclusions.
During diagnosis and treatment planning of ante-rior open bite problems, the orthodontist must iden-tify risk factors such as innate growth problems,excessive epipharyngeal lymphoid tissue, respirationproblems, tooth eruption problems, compensatorytongue thrust during swallowing, and/or digit-suck-ing habits. This article will try to increase awarenessthat anterior tongue rest posture is also an impor-tant risk factor for anterior open bite. The author willshow that an effective treatment method can modifyanterior tongue rest posture to avoid relapse of ante-rior open bite. Anterior tongue rest posture is clini-cally significant due to its long duration. An individ-ual who has anterior tongue rest posture interposesthe tongue between the incisors many hours per day.
This posture impedes incisor eruption and maintainsan anterior open bite. Anterior tongue thrust is notas significant clinically because the short duration ofthe thrust (1- to 3-second maximum during swallow-ing12) does not affect tooth position. Moorrees andLear have shown that a person swallows only 1200to 1500 times in a 24-hour period.13
The objective of this paper is to demonstrate thelong-term clinical results of closing anterior open bitewith intraoral spurs. The spurs force a change inanterior tongue rest posture, which in turn allowsincisors to erupt, closing the anterior open bite. Spurwear during orthodontic treatment of anterior openbite improves posttreatment stability.14 This effectmay be due to a permanent modification of anteriortongue rest posture.
Huang et al14 investigated the effect of spur ther-apy on the stability of anterior open bite correction.The anterior open bite sample consisted of 33patients (26 growing, 7 nongrowing) with an averageof 5 years posttreatment. The sample was providedby Drs Justus, Kennedy, Kokich, Little, and Turpin. Toensure that the sample would be representative,treatment success was not a criterion used in sam-ple selection. The results of this study confirmed thatthere was a statistically significant increased long-term stability in corrected anterior open bite treatedwith spur appliances. The patients maintained theircorrection many years out of retention. All patients inthe adult sample had incisor contact. Although 17%of the patients in the growing sample did not haveincisor contact, all of them had a positive overbitepostretention. The study concluded that stability ofanterior open bite correction is apparently related toa modification in anterior tongue rest posture due tothe spurs in both growing and nongrowing patients.
HISTORHISTORY OF ANTERIOR Y OF ANTERIOR OPEN BITE TREAOPEN BITE TREATMENT TMENT USING INTRAORAL SPURSUSING INTRAORAL SPURS
Rogers15 mentioned using intraoral spurs to modifytongue rest posture to close anterior open bite in hispatients. Parker16 used intraoral sharpened spurssoldered to the lingual surface of the maxillary cen-tral incisor bands. He demonstrated dramatic clo-sure of anterior open bite malocclusions usingspurs. The results achieved by Parker were impres-sive. However, this author hesitated to place intrao-ral sharpened spurs on his patients due to fear ofprovoking psychologic problems and alienating par-ents and patients. The author’s concerns about thespur method were alleviated after Haryett et al17
concluded that no psychologic problems arose from
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using any type of appliance, including spurs, toarrest thumb-sucking habits, provided there wasgood rapport between doctor and patient. They alsoconcluded that a spur appliance was more effectivein arresting finger habits and in correcting anterioropen bite than a crib with no spurs.
The author agreed with these conclusionsbecause a crib without spurs simply restrains, anddoes not retrain, the tongue, while spurs discouragethe tongue from resting against them. This can beobserved clinically because the tongue is scored bythe crib appliance, while no marks or bruises can beseen on the tongue when using spurs. This indicatesthe establishment of a new tongue posture probablydue to a nociceptive or proprioceptive reflex. More-over, tongue pressure on a crib appliance could drivethe supporting molars mesially, creating a Class IImolar relationship or aggravating an already presentClass II malocclusion.
Convinced that spur therapy had a place in ortho-dontics and that patients’ mental health would notbe damaged, the author decided to try this methodof closing anterior open bite. He gave a copy ofParker’s article to all his patients in orthodontictreatment during the early 1970s whose open biteswould either not close or failed to remain closed.Having convinced them that the method might work,he cemented an intraoral spur appliance in each ofthese patients. Six years later, after achieving thesame successful results as reported by Parker andby Haryett et al, the author published a paper18 oncorrection of anterior open bite with spurs. Nearly 20years later, Huang et al14 confirmed that long-termstability could be achieved with this method.
DESCRIPTION OF INTRAORALDESCRIPTION OF INTRAORALSPUR APPLIANCESPUR APPLIANCE
The intraoral spur appliance the author uses is dif-ferent than that used by Parker. The maxillary lingualarch with spurs used by the author is a more versa-tile appliance for modifying anterior tongue rest pos-ture than spurs on incisor bands for the followingreasons:
1. It allows expansion or reduction in intermolarwidth.
2. It inhibits molar eruption.3. Spurs can be placed anywhere along the arch
(which allows correction of both anterior and pos-terior open bites).
4. It permits headgear wear by welding buccal tubeson the molar bands to which the lingual arch issoldered.
5. It can arrest finger habits.6. It is inexpensive.7. It is easy to construct in the office.
The spur appliance recommended by the author(Fig 1) is constructed from 0.045-inch stainless steelwire (similar to a mandibular lingual arch) to whicheight short, sharpened 0.026-inch spurs, 3 mm inlength, are soldered to the anterior part. The spursare positioned 3 mm away from the cingulae of themaxillary incisors and are directed at an angle(downward and backward) to encourage correcttongue posture, with the tip of the tongue behind themaxillary central incisor papilla. The spur applianceis soldered to maxillary molar bands and cemented.The anterior open bite usually takes 6 to 8 monthsto close after appliance cementation, but may takelonger in some patients.
The following patient illustrates the typical correc-tion of anterior open bite achieved with spurs.
Patient A
Patient A is a boy 9 years of age with a Class I ante-rior open bite malocclusion with a symmetric 6-mmdental open bite extending from lateral incisor to lat-eral incisor (Figs 2a and 2b). The crowns of the max-illary lateral incisors had a distal inclination, due to amesial eruption path of the permanent caninesagainst the roots of the lateral canines, and the max-illary left deciduous canine was in lingual crossbite(Fig 2b). An anterior tongue rest posture was noted(Fig 2c). There was no history of a digit-sucking habit,no respiration problems were noted, the patient hadnormal skeletal cephalometric values, and there wasno family history of hyperdivergency. The patient andhis parents were shown the abnormal anterior
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Fig 1 Recommended intraoral spur appli-ance. Spurs are invisible when viewed fromthe front.
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Fig 2 Patient A. (a,b) A 9-year-old boy with an anterior open bite. Initial facial and intraoral photograph. Note distalinclination of the maxillary lateral incisor crowns. (c) Anterior tongue rest posture. (d) Occipital traction facebow. (e)Intraoral photograph 6 months into headgear treatment. There has been no improvement in the anterior open bite.(f,g) Intraoral spur appliance. (h) Intraoral photograph of spurs and tongue taken 1 month after spur appliancecementation. There are no bruises on the tongue, which is probably due to a protective reflex. (i to k) Intraoral pho-tographs taken 12, 24, and 30 months after cementing the spur appliance. There has been closure of the anterioropen bite, probably due to the establishment of a new tongue rest posture encouraged by the spurs.
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tongue resting posture of the patient and also cor-rect tongue rest posture. They were informed of thepossibility that the open bite might not self-correctwith orthodontic treatment due to the abnormaltongue rest posture. In the event the open bite didnot self-correct, spur therapy was presented as analternative. The treatment plan included extractionof deciduous maxillary canines (to help redirect theeruption path of the permanent canines), wearing ofoccipital pull headgear (to inhibit maxillary molareruption and maxillary vertical posterior growth), andallowing the anterior open bite to self-correct. After 6months of headgear treatment (Fig 2d), good rapportwas established with the patient and his parents.Since the anterior open bite had not improved bythis time (Fig 2e), patient and parents consented tothe spur method. A lingual arch with spurs (Figs 2fand 2g) was soldered to the maxillary molar bandsand cemented. The patient adapted well to the spurs(Fig 2h). The incisors erupted in the followingmonths, closing the anterior open bite (Figs 2i to 2k).Note that the maxillary permanent canines wereable to erupt uneventfully and that the axial inclina-tion of the lateral incisors autocorrected.
Since patient A had an anterior open bite of 6 mmfrom canine to canine, his open bite was considered“simple” and therefore had a high probability, accord-ing to Worms et al,19 of self-correction. (Worms etal19 investigated the incidence of anterior open bitein a population of 1500 Navajo children, 7 to 21years of age. They classified the severity of open biteas pseudo, simple, or compound, following Moyers’classification.20 The investigators drew longitudinalinferences from the cross-sectional data. They sug-gested that 80% of pseudo and simple open bitesprobably have spontaneous self-correction. They alsospeculated that compound open bites are probablynot self-correcting; the incidence of these increasedfrom 2% at 7 years of age to 10% at 21 years of age.)However, since patient A did not have any lymphoidtissue problem or any noticeable respiration problemand had normal vertical skeletal parameters with lipcompetency (anterior oral seal), it was believed thatthis open bite would not self-correct. If this open bitehad not been treated while the author and patientwaited for a self-correction that did not occur, manyproblems could have developed. These include anincreased probability of incisor root resorption,1
molar wear due to the lack of a mutually protectedocclusion, posterior crossbite due to a low tongueposture, and emotional problems due to diminisheddental esthetics during speech and smiling. In addi-tion, the probability of having to resort to more com-plicated orthodontic mechanics (and even surgicalcorrection) in later life also would have increased.
LONG-TERM RESULLONG-TERM RESULTS WITH TS WITH INTRAORAL SPUR APPLIANCEINTRAORAL SPUR APPLIANCE
The author has treated many dental and skeletalanterior open bite malocclusions using the methoddescribed for patient A. The following case reportsillustrate the typical long-term results with the lingualspur appliance.
Patient B
Patient B is a girl 8 years 1 month of age (Fig 3a)with a Class I anterior open bite malocclusion and asymmetric 3-mm dental open bite extending fromlateral incisor to lateral incisor. A complete posteriorright lingual crossbite (molar to canine) was present,due to a narrow maxilla (Fig 3c). A nocturnal thumb-sucking habit was present and anterior tongue restposture was noted. The patient had normal verticalskeletal cephalometric values (Fig 3b), no respira-tion problems were noted, and there was no familyhistory of hyperdivergency. The patient and her par-ents were shown the abnormal anterior tongue restposture and also the correct tongue rest posture.They were informed that due to her abnormaltongue rest posture, the open bite might not self-cor-rect despite eliminating the posterior crossbite andarresting the thumb-sucking habit. In the event theopen bite did not self-correct, spur therapy was pre-sented as an alternative. The treatment planincluded rapid maxillary expansion (RME), convinc-ing the patient to stop the sucking habit, and allow-ing the anterior open bite to self-correct. The RMEtreatment was instituted with successful results (Fig3d). During the RME treatment, good rapport wasestablished with the patient and her parents. In thisperiod, the patient was unable to stop her thumb-sucking habit and the anterior open bite had notimproved (Fig 3d). The patient was anxious for helpin arresting this habit, so she and her parents con-sented to the spur method. A lingual arch with spurswas soldered to maxi l lary molar bands andcemented (Fig 3e). The patient adapted well to thespurs, and the incisors erupted during the followingmonths, closing the anterior open bite (Figs 3f to3h). The posttreatment facial photograph shows apleasing upper-lip smile line (Fig 3i). The posttreat-ment radiograph demonstrates a positive incisoroverbite (Fig 3j). Seventeen years later (Figs 3k to3n), both the corrected posterior crossbite and thecorrected anterior open bite seem stable (Fig 3l) inspite of a vertical growth pattern (Fig 3o). This stabil-ity is probably due to the establishment of a normaltongue rest posture.
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a
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Fig 3 Patient B. The patient is a girl, 8 years 1 month of age. (a) Initial facial photograph. (b) Initial radiograph,which demonstrates the anterior open bite. (c) Initial intraoral photograph. Note the anterior open bite and posteriorright crossbite. (d) Post–rapid maxillary expansion intraoral photograph taken 3 months after the start of treatment.There has been no improvement in the anterior open bite. (e) Intraoral photograph taken at spur appliance cementa-tion. Patient is 8 years 4 months of age. (f to h) Intraoral photographs taken at 8 years 4 months, at 8 years 7months, and at 9 years 9 months of age. The appliance was removed when the patient was 9 years 9 months ofage, 6 months after the anterior open bite had closed. (i,j) Posttreatment facial photograph and radiograph taken at13 years 10 months of age. A pleasing upper-lip smile line and a positive overbite with incisal contact were estab-lished. (k to n) Photographs and radiograph taken at 26 years 11 months of age, 17 years posttreatment withoutretention. Note the stability of the corrected anterior open bite and the posterior crossbite. A positive overbite with-out incisal contact is evident. (o) Superimposition of radiographic tracings at 8 years 1 month of age, 13 years 10months of age, and 26 years 11 months of age. A vertical growth pattern is demonstrated.
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Patient C
Patient C is a woman 34 years 7 months of age (Fig4a) with a Class II, Division 1 skeletal anterior openbite malocclusion with a symmetric 5-mm open biteextending from lateral incisor to lateral incisor (Fig4c). Her mandibular first molars were missing. Ahyperdivergent cephalometric pattern was present(Fig 4b) and an anterior tongue rest posture wasnoted (Fig 4d). In addition, the patient had a protru-sive profile (Fig 4e). No respiration problems werenoted. The patient was shown her abnormal tonguerest posture and also the correct tongue rest pos-ture. She was informed that due to her abnormaltongue rest posture, the open bite might not self-cor-rect even with orthodontic treatment. In the eventthe open bite did not self-correct, spur therapy waspresented as an alternative. The treatment plan
included retraction of maxillary and mandibularincisors by closure of the mandibular molar spacesand extraction of two maxillary first premolars, use ofoccipital traction headgear and full appliances, andallowing the anterior open bite to self-correct. After 2years of headgear treatment and orthodontic ther-apy, the open bite had not closed, even though thepatient was now able to close her lips with no strain.Good rapport had been established with the patientand she consented to the spur method. A lingualarch with spurs was soldered to maxillary molarbands and cemented. The patient adapted well tothe spurs. The incisors erupted in the followingmonths, closing the anterior open bite (Fig 4f). Sevenyears later (Figs 4g to 4i), the corrected anterior openbite seems stable (Fig 4j) in spite of a hyperdivergentpattern (Fig 4k). This stability is probably due to theestablishment of a normal tongue rest posture.
Fig 4 Patient C. The patient is a woman 34 years 3 months of age. (a) Initial facial photograph. Note the anterioropen bite. (b) Initial radiograph, which demonstrates the anterior open bite with skeletal hyperdivergency. (c) Initialintraoral photograph. (d) Close-up of the initial facial photograph, which shows an unconscious anterior tongue restposture. (e) Initial facial profile photograph, which demonstrates lip protrusion. (f) Radiograph taken immediatelybefore debonding when patient was 38 years 5 months of age. The anterior open bite has closed after 22 months ofspur appliance wear. (g to i) Photographs taken when patient was 45 years 10 months of age, 7 years posttreat-ment. Note the stability of the corrected anterior open bite, the pleasing upper-lip smile line, and the improved facialprofile. (j) Radiograph taken when patient was 45 years 10 months of age. Note the positive overbite with incisalcontact. (k) Superimposition of radiographic tracings when patient was 34 years 3 months of age, 38 years 5months of age, and 45 years 10 months of age.
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The etiologic factor for anterior open bite in theclinical cases described above was probably an ante-rior tongue rest posture, because the open bitesclosed and remained closed many years postreten-tion following the use of spurs. This occurred despitethe vertical growth pattern observed in two of thesecases. Supported by the research carried out byHuang et al,14 the author concluded that anteriortongue rest posture is a frequent risk factor for ante-rior open bite.
In growing Class II patients with anterior openbite, the author recommends simultaneous use ofoccipital high-pull facebow headgear with the spurappliance. This type of headgear helps to inhibitboth vertical and horizontal maxillary growth. Inpatients with a Class I malocclusion with anterioropen bite, parietomandibular vertical pull gear (Fig5) is recommended to intrude both maxillary andmandibular molars. The parietomandibular gear,constructed in-office, consists of a circumferentialheadcap to which a vertical elastic strap is hookedanterior to the ear lobes. The elastic strap, which isidentical to that used for cervical facebow traction, ispositioned under the mandible behind the chin. Thistype of extraoral gear provides a true vertical force. Itis important to remember that for every millimeter of
molar intrusion, or noneruption, there is a 2- to 3-mm closure of the anterior open bite. Thus, it isadvantageous to inhibit molar eruption with thisextraoral appliance while simultaneously allowingincisor eruption by not allowing the tongue to pos-ture between maxillary and mandibular incisors. Theauthor recommends posttreatment nighttime wearof the parietomandibular gear to reduce the possibil-ity of open bite relapse.
NEUROPHYSIOLOGY OF NEUROPHYSIOLOGY OF INTRAORAL SPURSINTRAORAL SPURS
The case reports that the author has shown andthe research by Huang et al14 demonstrate thatanterior open bite malocclusions corrected withspurs have long-term postretention stability. If theetiologic factor was not anterior tongue rest pos-ture, it would be difficult to explain why the anterioropen bite closed with spur wear and experiencedno relapse. The author proposes that this is due toa modified tongue rest posture. The neurophysio-logic basis for using the spur appliance involves theform-function concept. The neural pathways thatallow a change in anterior tongue rest posture are
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a b c
Fig 5 Three designs of the parietomandibular traction appliance to intrude both maxillary and mandibular molars.This appliance provides a true vertical force.
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the lingual nerve, which is afferent or sensory, andthe hypoglossal nerve, which is efferent or motor.The spurs alter orofacial function, resulting in achange in form. In other words, the sensory input tothe brain is modified by the spurs. This propriocep-tive change leads to an altered motor response,resulting in a new normal tongue rest posture(change in function) that allows the incisors toerupt (change in form).
To avoid relapse of a corrected anterior open bite,the changed motor response, a nociceptive reflex,has to be permanently imprinted in the brain(learned). The learning process occurs because amovement that has been elicited repeatedly by suc-cessive stimuli may, after a while, be evoked withoutthe need of the conditioning stimulus, since it hasbeen imprinted in the cerebral cortex (Fig 6).
Haryett et al,21 in a 3-year follow-up study, found a91% success rate in arresting thumb-sucking habitswhen a cemented intraoral spur appliance was wornfor 10 months compared to a 64% success ratewhen the appliance was worn for only 3 months. Tak-ing these results into account, the author suggeststhat the spur appliance be nonremovable andremain in the mouth for at least 6 months after theopen bite has closed.
CLINICAL RECOMMENDACLINICAL RECOMMENDATIONS TIONS AND DISCUSSIONAND DISCUSSION
At the end of active orthodontic treatment, somepatients, particularly those who have had an anterioropen bite corrected with a spur appliance, want theirmaxillary removable retainer to have spurs to pre-vent relapse. The author believes that this is a goodidea if the patient so desires. However, if the patientdid not have a cemented spur appliance duringorthodontic treatment and the open bite relapsed, aremovable appliance with spurs will not be success-ful because it would probably not be worn full-time.Part-time wear of a removable spur appliance is noteffective in closing open bites; this is analogous tosomebody who wishes to quit smoking but avoidssmoking only part of each day.
Many patients are not willing to comply with full-time removable spur wear and, consequently, theretainer might not be worn at all. This places maxil-lary incisor alignment in jeopardy. It takes 2 to 3weeks for patients to adapt to speaking, swallowing,and eating with cemented spurs. Therefore, it is notreasonable to expect patients who have never usedfixed spurs to wear a removable spur appliance full-time until the bite closes.
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Spurs (on a maxillary lingual arch)
Stop the sucking habit
Encourage mature tongue rest posture
Allow incisors to erupt closing the anterior open bite
Establish new neuromuscular pattern (given enough time)
Diminish the probability of relapse
Inhibit maxillary molar eruption
Fig 6 Flowchart of the neurophysi-ologic basis for changing anteriortongue rest posture.
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When an orthodontist is faced with an anterioropen bite relapse, the author recommends the following:
1. Explain to the family the possibility that therelapse is due to an anterior tongue rest postureproblem.
2. Determine whether orthognathic surgery is indi-cated.
3. If surgery is not advisable, recommend acemented reminding appliance with spurs andthe use of parietomandibular extraoral gear,which would be worn at night.
4. Encourage the family by giving them a copy of anarticle that shows cases successfully treated withthe spur appliance.
5. When cementing the reminding appliance, besure to have a holding appliance on the mandibu-lar arch to avoid incisor crowding, which can read-ily occur because the tongue will not be there tosupport the mandibular incisors. A mandibularfixed canine-to-canine retainer or a removableretainer worn during the night is adequate.
6. Bond a maxillary canine-to-canine retainer whilethe spurs are in the maxillary arch to ensure thatmaxillary incisor alignment is maintained.
7. Allow the spur appliance to remain in the mouthfor at least 1 year, even though the bite may haveclosed in 6 to 8 months. This is the length of timeit normally takes to close an open bite with a spurappliance.
8. Keep reminding the family that the appliance isnot just to arrest a digit-sucking habit but also tocorrect abnormal tongue rest posture.
9. Do not expect the bite to close immediately.
To avoid alienating patients or parents, the authorrecommends referring to the maxillary lingual archwith spurs as “the reminding appliance” instead of“the sharpened spur appliance.” A mandibular lin-gual arch with spurs is probably as useful as a maxil-lary one, except that it is visible and patients mightfind it objectionable since they would be continu-ously asked about the appliance.
Contraindications to the spur appliance are as follows:
1. Diminished muscular control.2. Abnormally large tongue.3. Maxillary lateral incisors have not yet erupted
(indicating that the central incisors might still beerupting; ie, closing a transitional anterior openbite).
4. Good rapport has not been established.5. Stressful periods in patient/parents lives (ill-
ness, divorce, school exams, etc).6. No desire to quit digit-sucking habit.7. Immaturity (lack of understanding treatment
goals).8. Increased nasal resistance, allergic rhinitis, or
enlarged tonsils and/or adenoids (particularlyduring an acute episode).
9. Ongoing speech therapy. (If indicated, speechtherapy should preferably be instituted after thebite has closed because the speech therapistcan work more effectively with a child who doesnot have an anterior open bite.)
10. Bad oral hygiene.11. Severe skeletal dysplasia (including lip incompe-
tency) where orthognathic surgery is part of thetreatment plan. Spur therapy for patients whowill require orthognathic surgery should be con-sidered postsurgically and only if an open bitebegins to reappear.
It is critical that parents and patients be madeaware of why the individual has an anterior openbite. Remember that good rapport must be estab-lished before cementing the appliance. Therefore,conventional or thodontic treatment can beattempted for a few months before cementing thespur appliance. This allows the orthodontist toobserve whether the bite is closing without a spurappliance and also provides sufficient time for theorthodontist to establish the necessary rapport withthe patient. One can additionally earn the family’strust by introducing other patients presently in spurtreatment.
When cementing the spur appliance, the familyshould be informed that there will be some initial dif-ficulty speaking, eating, and swallowing. All of theseproblems will be resolved in 2 to 3 weeks. Duringthis period, patients are asked to cover their spurswith cotton. The tongue is thus protected and cangradually adapt to the spurs. The patients shouldalso be advised to pay particular attention tohygiene on the lingual aspect of the maxillaryincisors because the spur appliance makes brushingthis area more difficult. During the subsequentmonthly appointments, it will be necessary to bendthe lingual arch downward, with a three-prong pliers,to prevent the lingual arch from impinging on thepalatal tissue as the erupting maxillary incisorsdescend. One must not overdo the bends, thus pre-venting the mandibular incisors from touching thelingual spur appliance.
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CONCLUSIONSCONCLUSIONS
1. The selection of myofunctional therapy with intra-oral spurs for correction of anterior open bite hasa wide range of applications in the overallscheme of open bite treatment.
2. The effectiveness of the spur appliance, both inclosing anterior open bite and in achieving long-term stabil ity, has been validated throughresearch.
3. Although dental and skeletal malrelationshipscan be corrected, the stability of anterior openbite treatment will improve if etiologic factors forthe open bite are eliminated.
4. Since anterior tongue posture and the orofacialmusculature might play primary roles, not justadaptive ones, they must be addressed in ortho-dontic therapy to minimize relapse.
5. The etiology of anterior open bite is complex andmultifactorial. Thus, it behooves the clinician tofind out the etiologic factors for the open bite ineach patient under his/her care to thus deter-mine treatment that will not result in relapse.
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