Academic year 2014-2015

AESTHETIC OUTCOME OF AUTOTRANSPLANTED

PREMOLARS REPLACING MAXILLARY INCISORS. A RETROSPECTIVE STUDY.

Stéphanie TOURNE

Promotor: Prof. dr. G. De Pauw

In partial fulfillment of the requirements for the degree of master in orthodontics

Faculty of Medicine and Health Sciences, Department of Dentistry

Academic year 2014-2015

AESTHETIC OUTCOME OF AUTOTRANSPLANTED

PREMOLARS REPLACING MAXILLARY INCISORS.

A RETROSPECTIVE STUDY

Stéphanie TOURNE

Promotor: Prof. dr. G. De Pauw

In partial fulfillment of the requirements for the degree of master in orthodontics

Faculty of Medicine and Health Sciences, Department of Dentistry

De auteur(s) en de promotor geven de toelating deze Masterproef voor consultatie

beschikbaar te stellen en delen ervan te kopiëren voor persoonlijk gebruik. Elk ander

gebruik valt onder de beperkingen van het auteursrecht, in het bijzonder met

betrekking tot de verplichting uitdrukkelijk de bron te vermelden bij het aanhalen van

resultaten uit deze Masterproef.

Datum

(handtekening student(en)) (handtekening promotor)

(Naam student) (Naam promotor)

                  Acknowledgements_________________________________________________________________

First and foremost I offer my sincerest gratitude to my supervisor, Dr. L. Temmerman for the

support and correction throughout my thesis.

I would also like to thank Prof. dr. G. De Pauw who has helped me with his patience and

knowledge while allowing me the room to work in my own way. A special thanks goes to Dr.

Barendregt, Prof. dr. C. Politis and Dr. P. Plakwicz for their enthusiasm and data collection.

I also thank everybody else who supported me in any way during the completion of this

project.

Table  of  contents_________________________________________________________________

Introduc)on...............................................................................................................................1

Chapter  1:  General  introduc=on......................................................................................2

I.  Dental  trauma........................................................................................................................3

  1.  Prevalence  and  risk  factors...........................................................................................3

  2.  Psychological  aspects....................................................................................................4

  3.  Impact  on  the  alveolar  process.....................................................................................4

II.  Treatment  op0ons................................................................................................................5

  1.  Orthodon)c  space  closure............................................................................................5

  2.  Prosthe)c  rehabilita)on...............................................................................................7

    2.1  Dental  implants.................................................................................................7

    2.2  Resin  bonded  bridge  (RBB)................................................................................8

  3.  Autotransplanta)on.....................................................................................................9

III.  Autotransplanta0on..........................................................................................................10

  1.  Indica)ons..................................................................................................................10

  2.  GraL  selec)on............................................................................................................11

  3.  Dental  )ssue  reac)ons  aLer  autotransplanta)on.....................................................12

    3.1  Periodontal  healing.........................................................................................12

    3.2  Root  development...........................................................................................13

    3.3  Pulp  healing.....................................................................................................13

  4.  Post  transplanta)on  treatment  and  follow-­‐up………………..........................................14

  5.  Survival-­‐  and  success-­‐rate..........................................................................................16

IV  Smile  aesthe0cs..................................................................................................................18

  1.  Smile  design................................................................................................................18

    1.1  Facial  aesthe)cs..............................................................................................18

    1.2  Gingival  aesthe)cs...........................................................................................18

    1.3  Microaesthe)cs...............................................................................................19

    1.4  Macroaesthe)cs..............................................................................................19

  2.  Assessment  of  the  smile  aesthe)cs............................................................................21

    2.1  Subjec)ve  methods.........................................................................................21

    2.2  Objec)ve  methods..........................................................................................21

Chapter  2:  Aesthe=c  outcome  of  autotransplanted  premolars  replacing  

maxillary  incisors.  A  retrospec=ve  study.....................................................................24

I.  Research  of  the  literature....................................................................................................25

  1.  Medline.......................................................................................................................25

  2.  Web  of  science...........................................................................................................26

  3.  Cochrane  Library.........................................................................................................27

II.  Aim......................................................................................................................................28

III.  Material  and  Methods.......................................................................................................29

  1.  Subjects.......................................................................................................................29

  2.  Data  collec)on............................................................................................................30

    2.1  Intra-­‐oral  pictures............................................................................................30

    2.2  Gingival  thickness............................................................................................30

    2.3  Plaque  and  Ginigival  Index…………………………………………………………..………………31

    2.4  Addi)onal  informa)on....................................................................................31

  3.  Aesthe)c  evalua)on...................................................................................................32

  4.  Pa)ent’s  aesthe)c  sa)sfac)on...................................................................................33

IV.  Sta0s0cal  tests…………………………………………………………………………………………………..………….34

  1.  Error  of  the  method;  Intra-­‐observer  reliability……………………………………………………….34

    1.1  Dahlberg’s  Formula……………………………………………………………………………………..34

    2.1  Intraclass  correla)on…………………………………………………………………………………..34

V. Results……………………………………………………………………………………………………………………………35

  1.  Study  sample..............................................................................................................35

  2.  Aesthe)c  evalua)on...................................................................................................37

  3.  Addi)onal  parameters................................................................................................40

  4.  Pa)ent’s  sa)sfac)on...................................................................................................40

VI.  Discussion………………………………………………………………………………………..……………………………44

  1.  Aesthe)c  evalua)on……………………………………………………………………………………………….44

  2.  Type  of  restora)on………………………………………………………………………………………………...45

  3.  Orthodon)c  treatment…………………………………………………………………………………………..46

  4.  Gingival  thickness…………………………………………………………………………………………………..46

  5.  Gingivi)s  and  Plaque  Index………………………………………………………………………………….…47

  6.  Limita)ons………………………………………………………………………………………..……………………48

VII.  Conclusions………………………………………………………………………………………………..…………………50

VIII.  Bibliography………………………………………………………………………………..………………………………51

IX.  Appendix…………………………………………………………………………………..…………………………………..57

                      Abstract_________________________________________________________________

Purpose: The aim of this study was to evaluate the aesthetic outcome of autotransplanted

premolars to the anterior maxilla.

Materials and Methods: A cross-sectional study including 32 patients who have had an

autotransplantation of a premolar to the maxillary incisor region, was conducted. Different

restorations were chosen for the transplanted premolar: buildup with composite or porcelain

laminate veneer. The mean observation time was 7 years (range: 1-23 years). The aesthetic

outcome was rated using the Pink Esthetic Score (PES) and the White Esthetic Score (WES).

Patients rated aesthetics by means of 100 mm visual analogue scales.

Results: Patients responded very favorably regarding the treatment outcome. According to the

PES and WES, 56% had acceptable aesthetics and 9% had an (almost) perfect outcome.

Thirty-four percent were aesthetic failures (PES and/or WES< 6), mainly due to a low WES.

Patients with a porcelain veneer scored significantly higher for the WES (p=0.026).

Conclusions: Patients responded very favorably regarding the treatment outcome.

The aesthetic outcome was disappointing in 34% of the cases. This result was mainly due to a

low WES. Laminate veneers might be better to provide a more aesthetic result.

                                   Introduc=on_________________________________________________________________

Orthodontic treatment planning may be difficult in patients with missing teeth, especially in

the anterior region. Tooth transplantation in young children and adolescents has become a

valid treatment option. Over the past 20 years the procedure of autotransplantation of teeth

has become very successful. The long-term survival rates are high.

Nowadays, aesthetic appearance has become more important in addition to optimal function.

Hence, clinical success of a transplanted tooth also depends on harmonious integration of the

transplant in the patient’s mouth.

The published literature contains little comprehensive studies concerning the aesthetic results

of premolar autotransplantation. The aim of this study is to evaluate the aesthetic outcome of

transplanted premolars to the maxillary anterior region.

1

                                                         Chapter  I          General  introduc0on  

_________________________________________________________________

2

I.   Dental  trauma

The main cause of tooth absence in the maxillary frontal region is dental trauma. Loss of a

maxillary incisor has a major impact on a patient’s smile.

Trauma can cause direct tooth loss or can weaken a tooth considerably leading to its final loss

after a short or long-term period. Avulsion is a total displacement of the tooth out of its

socket, and occurs in 0.5-3% of traumatic injuries in the permanent dentition (1). The

maxillary incisors are the most frequently affected and it occurs mostly in children from 7 to 9

years old, because the bone around the tooth is not fully mineralised yet (2). An avulsed tooth

should not be replanted if there is advanced periodontal disease, if the alveolar socket is not

intact enough, if the extra-oral time was longer than 1 hour in dry conditions (2).

Reimplantation after a long extra-alveolar period can result in ankylosis and tooth loss (3).

Ankylosis can also appear after an intrusion injury. Other injuries which can cause tooth

extraction after trauma are resorption of the root structure due to periodontal damage, root

fracture and pulp infection. In cases of infection, an endodontic treatment is required.

However, in young children this treatment can weaken the tooth considerably, because of the

rather broad pulp canal (3).

1. Prevalence and risk factors

___________________________________________________________________________

In a review article of Bastone et al., the prevalence of dental trauma in children was ranged

between 6 and 34% (4). The prevalence of dental trauma differs considerably in various

studies due to differences in study design.

The oral factors that influence the risk for Traumatic Dental Injuries are overjet with

protrusion and inadequate lip coverage (5). The amount of overjet that increases the risk for

TDI is still in discussion. Another risk factor for dental trauma is human behaviour.

Hyperactive children, obese children, children with epilepsy etc. would have an increased risk

for TDI (6)(7)(8). Furthermore, one of the main causes for TDI is sports (9). Other causes of

TDI can be inappropriate use of teeth, oral piercings, traffic accidents etc. 3

2. Psychological aspects

__________________________________________________________________________________

In cases of early loss of a central incisor, one should not underestimate the psychological

aspects. Teenagers have various peer relationships, and they interact with many peer groups.

Adolescents go through a period of rapid physical, emotional and social changes (10). They

are very sensitive to impacts (like loss of a central incisor) and this may lead to long-term

psychological effects like depression and anxiety due to teasing (11). Replacing a visible lost

tooth will be important to reduce the negative social and psychological outcome. Oral health

influences people’s quality of life: How people look, speak, smile, chew, taste, and enjoy

food. The goal of treatment is to restore the capacity of people to make social contacts, as

well as restoring the functional aspect of the lost tooth (12).

3. Impact on the alveolar process

__________________________________________________________________________________

Another consequence of the premature loss of teeth is the changes to the alveolar process. The

alveolar process is a tooth-dependent tissue that develops in conjunction with the eruption of

the teeth. The volume as well as the shape of the alveolar process is determined by the form

of the teeth, their axis of eruption and inclination (13). Subsequent to the loss of teeth, the

alveolar process will undergo atrophy (11). The greatest amount of bone loss occurs in the

horizontal dimension, mainly on the facial aspect of the ridge. The vertical loss of ridge

height is most pronounced in the buccal aspect. This resorption results in the relocation of the

ridge to a more palatal/lingual position and a narrower and shorter ridge (14). The size of the

residual ridge is reduced most rapidly in the first 6 months, but bone resorption will continue

throughout life at a slower rate (15). However, sufficient bone volume is essential to obtain

optimal functional and aesthetic prosthetic reconstruction (16).

4

                 II.                      Treatment  op=ons  in  case  of  loss  of  a  maxillary  incisor

When a maxillary incisor is missing, various treatment options are possible. The choice of the

best treatment alternative for a missing maxillary incisor is very individual. The treatment

plan may depend on various factors as occlusion, space conditions, tooth morphology, facial

morphology, etc (17-19).

Possible treatment options for a missing incisor are: orthodontic space closure, prosthetic

rehabilitation, autotransplantation.

1. Orthodontic space closure

_____________________________________________________________________________________________________

Orthodontic space closure is one of the treatment options when a maxillary incisor is missing.

In case of a missing central incisor, orthodontic space closure is possible but is not used

frequently, because of the difficulty to obtain a good aesthetic result.

A great advantage of space closure is that the patient will have exclusively natural teeth, and

the gingival tissues and interdental papillae will change in synchrony with the patients age

(20). Also, a permanent result is reached at an early age (20). Disadvantages of space closure

are the need for enameloplasty in order to improve the aesthetic result and the more elaborate

orthodontic treatment (21). Space closure is recommended for 2 malocclusions: Angle class II

malocclusion with no crowding in the mandibular arch, and Angle class I malocclusion with

crowding in the mandibular arch, and where extractions are necessary (19, 22-24).

Not only the type of malocclusion, but also the tooth morphology is of great importance (24,

25). For example, Brough et al. (26) investigated the influence of canine morphology, size and

shape on the smile attractiveness in cases of canine substitution in cases of a missing lateral

incisor. Increasing canine gingival height, canine width, canine tip height and pointed canines

were perceived to be less attractive. Also, facial morphology is of importance. A dished-in

profile is a contra-indication for space closure, to keep the lips as much supported as possible.

5

When a maxillary lateral incisor substitutes a central incisor, or when a maxillary canine is

replacing a lateral incisor, some finishing criteria should be taken into account to perceive an

aesthetic result (20, 22, 25, 27, 28):

1. Taking gingival heights as a guide for tooth positioning

2. Matching the shape of the temporary restoration with the adjacent tooth. This

allows the orthodontist to place the teeth in the correct position

3. Positioning of the canine and first premolar so that the arch form is largely maintained

4. Rotation of the premolar and molar mesially

5. Optimal crown torque for canine, first- and second premolar.

6. Aesthetic recontouring of the canine to lateral incisor with resin build-ups or porcelain

veneers.

7. Bleaching of dark canines

8. Properly finished occlusal contacts and long-term retention to overcome the tendency

of space- reopening.

9. Simple surgical procedures for localised clinical crown lengthening

When taken these criteria into account, a satisfying result can be achieved. Czochrowska and

co-workers (17) evaluated the overall aesthetic appearance of mesialised lateral incisors by

comparing with the contralateral tooth and concluded that space closure can be recommended

if the right indications are present. Robertson et al. (29) concluded that patients, who were

treated with canine substitution when the lateral incisor was missing, are generally more

satisfied than the patients who had a prosthetic replacement of the missing incisor. In general,

opinions about the most aesthetic treatment option depend on personal opinion (21). Patients

with the maxillary incisor spaces closed would be healthier periodontally (24).

6

2. Prosthetic rehabilitation_____________________________________________________________________________________________________

The advantage of replacing maxillary incisors prosthetically includes maintaining the canine

at its natural position within the dental arch and maintaining the morphology of canine and

first premolar (21). Prosthetic rehabilitation of the open space is recommended in class III

cases or class I cases with no space deficiencies (22). This is in contrast with the findings of

Rosa et al. (20, 28) who do not see a class III malocclusion as a contra-indication for

orthodontic space closure.

There are many possible prosthetic options for the replacement of a missing maxillary incisor,

as a dental implant, a resin-bonded bridge, a conventional bridge or a partial denture.

Conventional bridgework and partial dentures are not commonly used treatment options,

because of their invasive nature and lack of comfort in young patients.

2.1 DENTAL IMPLANTS

An option for replacing a missing maxillary incisor is the use of a dental implant. Nowadays,

it is well known that single-tooth implants have very good long-term results regarding

survival-rate and function (19, 30, 31). An advantage of dental implants, comparing to a resin

bonded bridge is the maintenance of the alveolar bone (19).

So far, a considerable number of studies dealing with implant aesthetics have been published

(32). In general, these studies deal with short-term assessment of implant aesthetics and show

good results in well-selected cases. On the other hand, long-term studies on single implants

are scarce. A long-term follow-up study of Dierens et al. (33), demonstrated that peri-implant

soft-tissue remains stable over 16-22 years. However, recession and eruption can be expected

at neighbouring teeth. In a study of Jemt and co-workers (34), it was concluded that single

implants increase the risk of gingival recession at the adjacent teeth. Nevertheless,

comparison of studies dealing with aesthetic assessment of dental implants should be done

with caution, due to differences in study designs (32).

On the other hand, the main disadvantage of dental implants is the time of implant placement.

7

Like an ankylosed tooth, an implant does not have any physiological eruption during growth

and no formation of alveolar bone takes place in synchrony with vertical growth (35). Infra-

occlusion of the implant will occur.

Nivedita et al. (36) reviewed the current literature regarding the use of dental implants in

growing patients, and concluded that one should wait for the completion of dental and skeletal

growth in order to obtain an aesthetically acceptable result, especially in the incisor region

(37). Because of continued facial growth, several years can elapse between the end of

orthodontic treatment and implant placement. During this period, the roots of the adjacent

teeth can reapproximate during retention. Even more, in a study of Olsen and Kokich (38),

11% of patients had enough relapse to prevent implant placement. A 6.3 mm intercoronal

space, 5.7 mm interradicular space and fixed retention were recommended in order to

maintain the space for implant placement later on.

2.2 RESIN BONDED BRIDGE (RBB)

Another treatment option for the replacement of maxillary incisors is the resin-bonded bridge.

According to Barber et al (39), resin bonded bridges (RBB) have several advantages. The

main advantage is the minimal tooth preparation needed for bonding. Therefore, the RBB is

considered to be a very conservative method for tooth replacement. A second advantage is the

easy rebonding, when debonded. A simple cleaning of the bridge-wing and the tooth surface

should be sufficient. Also, the RBB is less expensive compared to implants, fixed bridgework,

or partial dentures.

The main disadvantage of the RBB stated by Barber and coworkers (39) is the relatively high

failure rate (6-7% after 4 years). Although, a general improvement of debonding rate has been

seen over the years. Wyatt et al. (40) reviewed the current literature concerning failure- and

clinical success rates of the RBB. They concluded that the survival rates of the RBB are

between 63% and 85% after 5 years. Also, the debonde rate is higher in the mandible than the

maxilla. The RBB bridge can also be used awaiting future implant placement.

8

3. Autotransplantation_____________________________________________________________________________________________________

Autotransplantation is the non-traumatic transfer of an autogenous tooth from the donor

alveolus to the receptor alveolus. An autograft is a graft from one site to a different site in the

same person. Teeth can also be transplanted from one person to another. This type of

transplantation is called allotransplantation, but has a lower success rate due to

immunological reactions in the host’s body (41). Systemic research on autotransplantation

started in 1771 (Hunter), but failed mostly because of lack of knowledge of root resorption

and the disability to control infection. The last 20 years, autotransplantation has become a

reliable and predictable clinical procedure. The advantage of this kind of replacement is that

the tooth, as well as the bone is replaced without using the adjacent teeth (42). Tooth

transplantation can be used as a definitive treatment option, or as an interim solution before

implant placement.

TRANSPLANT IMPLANT

‘Biologic’ replacement Artificial’ replacement

Creates alveolar bone  

Needs alveolar bone

Normal periodontal membrane   Ankylosed (osseointegrated)

Adjustable position after surgery  

Nonadjustable

Erupts, in synchrony with neighbours during continues growth and eruption

 

Does not erupt

Normal interdental gingival papillae Frequently interdental gingival recession (particularly with 2 neighbouring implants)

Long-term observations (>40 years) Long-term observations lacking (>10-15years)

Table 1. (43) Comparison of outcome between autotransplantation of developing premolars and single-tooth implants after accidental loss of maxillary incisor.

9

                       III.       Autotransplantation

1. Indications__________________________________________________________________________________

The three main indications for autotransplantation of developing premolars are unevenly

distributed agenesis, agenesis of the mandibular second premolars, and accidentally lost or

congenitally missing maxillary central and lateral incisors in children. Also, when a

permanent molar is lost due to decay, it may be indicated to replace this tooth by a developing

third molar. Other indications could be replacement of ectopic teeth, developmental anomalies

of teeth, etc. (44).

Bone inductive properties are particularly useful when there has been traumatic loss of

anterior teeth with concomitant loss of supporting bone. For this reason autotransplantation is

frequently the treatment of choice in a dental patient with loss of a central incisor in whom

orthodontic extractions are indicated for correction of the malocclusion (45, 46). Presently, it

is not recommended to remove premolars where optimal occlusion exists. In normal occlusion

and in cases of class I or class II malocclusion, the adverse effects are more serious when

lower premolars are absent than when upper premolars are absent (46).

Furthermore, the patient has to meet certain criteria, listed by Lownie et al. (47):

1. There should be sufficient space in the arch for the transplanted tooth. If not, minor

orthodontic movements may be necessary.

2. The transplanted tooth should have a better prognosis than the remaining deciduous tooth.

3. The patient’s motivation and oral hygiene should be acceptable.

4. Other possible types of treatment should have been considered.

10

2. Graft selection__________________________________________________________________________________

The selection of the graft depends on crown as well as root anatomy. The dimensions of the

crown of the graft should be compatible with the recipient site. Crown anatomy can then be

modified after transplantation by the use of a porcelain crown or veneer. Also the root

anatomy of the graft should fill the recipient site. It should avoid contact with adjacent bone

and provide at least 1 mm of space to the adjacent roots. It is not exceptional that potential

grafts will exceed existing labio-palatal dimensions, especially if atrophy of the alveolar

process has taken place. In this case, the recipient site can be expanded surgically.

Especially the use of premolars is recommended with exception of the first maxillary

premolar because of its difficult atraumatic removal with double roots. The mandibular

premolars will usually fit into the maxillary anterior region after only minor adjustments,

whereas maxillary premolars will usually require surgical alternations in the socket area

including expansion of the socket. In addition, the dimension at the cervical aspect of the graft

is important. This must be in reasonable harmony with the contralateral tooth. Such harmony

can often be obtained if the graft is rotated 45° or 90° (the socket must be enlarged to

accommodate the root) (48). Mostly however, there is an adequate mesiodistal space created

by orthodontic treatment so that the transplant can be placed in an ideal position, namely 90°

rotated so that less labiopalatal reduction is necessary. In this position, gingivectomy may be

necessary to recreate symmetry (48).

As one can see in figure 1 (42, 49), root development is divided in different stages from 1 to

7. Stage 1 represents 1/4 root formation with open apex and stage 7 is complete root

formation with closed apex.

Kristerson et al. (50) identified the influence of root development on the success of

autotransplantation. In this study, 100 transplanted premolars were divided into different

stages of root development. 12 months after transplantation a clinical and radiographic

examination was performed. Periodontal healing without root resorption was related to the

stage of root development. It was concluded that transplantation of premolars with 1/2-3/4

root development provides a good chance of pulp survival, limited risk of root resorption and

ensures sufficient final root length (figure 2). This statement was confirmed by many authors

(51-54).

11

Figure 1. Seven different stages of root formation according to Moorrees et al.(49), modified by Kristerson et al. (42).

Figure 2 Pulpal and periodontal healing and root growth after transplantation related to stage of root development at the time of grafting (55).

3. Dental tissue reactions after autotransplantation__________________________________________________________________________________

3.1 PERIODONTAL HEALING

The key to a successful clinical outcome of a transplantation is the healing of the

periodontium. It is generally accepted that preservation of the periodontal ligament (PDL) is a

crucial factor for an optimal healing. In a previous transplantation experiment in monkeys by

Andreasen and Kristeron (56), it was postulated that the removal or drying of the PDL leads

12

to ankylosis or a resorption process. Also later, Andreasen et al. (57) showed that trauma to

the PDL of the transplant is the explanatory factor for the development of root resorption. In

the literature, three types of resorption have been described (57):

surface resorption, replacement resorption and inflammatory resorption.

3.2 ROOT DEVELOPMENT

The root development of a transplant is a less critical factor in the prognosis of the transplant

(50). Although, Mendes et al. (44) stated that the transplantation is successful if the roots

develop beyond their bifurcation.

Root development is attributed to Hertwig’s epithelial root sheath (HERS). HERS is a

bilayered epithelial sheath, formed by the fusion of inner and outer enamel epithelia below the

level of the crown’s cervical margin during tooth development (58). Findings show that some

of the transplants attain almost their final root length, which shows that HERS can function

normally after transplantation (55). Arrest of root development in other transplants is

attributed to damage of HERS during removal of the transplant (47). The exact role of HERS

in root formation is still unclear, but damage of it by premature occlusal loading can lead to

its breakdown. To attain a good final root length, the tooth germs should be placed in their

original level. Clinical observations indicate that the root growth of a transplant is arrested

when the tooth germ is placed in a functional position.

According to Slagvold and Bjercke, transplanted premolars have 1.3 mm shorter roots (59).

3.3 PULP HEALING

Examination of pulp healing is done clinically with a pulpal sensitivity test and

radiographically for monitoring of root canal obliteration. Most authors agree that pulp

healing is closely related to the stage of root development at the time of transplantation (48,

50, 60). Most immature transplanted teeth show both loss of sensitivity, as root canal

obliteration, due to the damage to vascular and nervous supply of the pulp. It is likely that

obliteration of the pulp is caused by ingrowth of connective tissue from the PDL into the pulp

chamber (52). This tissue stimulates formation of tertiary dentine, which leads to obliteration

of the pulp chamber. The clinical importance of root canal obliteration is the difficulty to

perform endodontic treatment, when necessary. However, pulp canal obliteration is not an

13

indication for endodontic intervention on a routine base, as the frequency of pulp necrosis is

not higher in obliterated teeth compared to intact teeth (61).

After transplantation, a healing process usually restores the content of the pulp canal with the

nervous supply (48, 55). In this point of view, teeth in which the apical diameter is too small

will have a greater risk of necrosis, because post-operative revascularisation is more difficult

(44). According to Andreasen (48), apical diameters above 1 mm have lower risks for pulp

necrosis. On the other hand, Laureys and co-workers (62) concluded that an apical diameter

smaller than 1 mm did not prevent revascularisation and ingrowth of vital tissue.

Unlike immature teeth, teeth with fully developed roots do not undergo pulpal repair (47, 48,

50). There are two explanations for this observation. First of all, the apical opening is too

small for revascularisation, and on the other hand, the longer the tooth, the longer the distance

for revascularisation. Therefore, transplants with closed or partially closed apices should be

treated endodontically after splint removal, as soon as the periodontal tissues have healed

(within 3 weeks after surgery) (50).

4. Post transplantation treatment and follow-up___________________________________________________________________________

One week post-transplantation the sutures can be removed. Most authors recommend clinical

and radiographic control after 4 to 8 weeks. Further clinical and radiographic controls should

be performed at 6 months, 1 year, 2 years and 5 years after transplantation (52, 57). Clinically,

tooth position, mobility, percussion, pocket depth and gingival condition should be checked.

Healing of the PDL starts 1 month after transplantation and is completed after 2 months. This

can be seen by reformation of the lamina dura. The pulp will react positively on sensibility

tests after 4 or 6 months. Most of the time, the response is smaller than before transplantation.

In many cases there is radiographic evidence of pulp revascularisation by obliteration,

whereas no sensibility reaction can be provoked.

The most common complications seen after tooth transplantation are lack of pulp canal

revascularisation and ankylosis or replacement resorption (45). Former is rare when the graft

has an open apex but can be treated by endodontic therapy. The latter is a more severe

complication, as eruption of the transplant is prevented and the root is substituted by bone. In

cases of ankylosis, a gradual resorption can be expected, and no good treatment is available.

14

Pulp necrosis is mostly diagnosed 4-8 weeks after transplantation, whereas root resorption is

diagnosed 1-6 months after transplantation (48, 57).

When reshaping the transplanted tooth, one should be aware of exposing dentine and making

the tooth accessible to bacterial invasion. Therefore, it is recommended to reshape/restore the

transplant before total canal obliteration has occurred. If necessary, endodontic treatment can

be started. Nowadays, composite build-ups and ceramic laminate veneers are most commonly

used for restoration of the graft. Because the root of a transplant develops a normal

periodontal ligament, orthodontic movement can be performed like every other tooth.

In many cases, orthodontic treatment after transplantation is necessary to increase aesthetic

results, or for other reasons. In those cases, pulp necrosis, due to strangulation of the

vascularisation entering the apical foramen, during orthodontic treatment, has to be prevented.

Therefore, orthodontic movement is recommended after periodontal healing and before pulp

canal obliteration. This is normally within 3 to 9 months after transplantation (55). Watanabe

(63) and Zacchrisson (43) recommend starting orthodontic treatment 3 to 5 months after

transplantation.

15

5. Survival and success rate (52, 63-69)__________________________________________________________________________________

Number of teeth

Success rate(%)

Survival rate (%)

Mean observation time

(Year ‘y’ and Months ‘m’)

Andreasen et al. (1990) (48) 370 96  (  C  r.f)

95    (iC  r.f)15  (C  r.f)95  (iC  r.f) 1-13 y

Kristerson  &  Lagerström  (1991)  (42)

50 82 (iC r.f) 92 (iC r.f) 7y,6m

Kugelberg  (1994)  (64) 45 / 82  (C  r.f)

96  (iC  r.f) 1-4 y

Lundberg & Isaksson (1996) (65)

278 84  (C  r.f)94  (iC  r.f)

84  (C  r.f)94  (iC  r.f) 5y, 6m

Czochrowska et al. (2002) (66) 33 79 (iC r.f) 90 (iC r.f) 26,4 y

Jonsson & Sigurdson (2004) (52)

40 92 (C r.f) 97 (C r.f) 10y, 4m

Watanabe et al. (2010) (63) 38 63 (C r.f) 86 (C r.f) 9,2y

Kvint  et  al.(2010)  (67) 269 81 (iC r.f) 90,7  

(iC  r.f) 4,8y

Gonnissen et al. (2010) (68) 73 57 (C r.f) 75 (C r.f) 11y

Plakwicz et al. (2013) (69) 23 100  

(iC  r.f)91,3  (iC  r.f) 2y, 11m

Table 2. Survival and succes rates after tooth transplantation (C r.f = complete root formation / iC r.f= incomplete root formation during transplantation).

16

Several studies have shown autotransplantation to be a reliable treatment alternative,

regarding its long-term survival and success rates (45) (Table 2). The success rate can be

defined as the percentage of transplanted teeth, meeting certain criteria as no ankylosis, pulp

revascularisation etc. The survival rate is defined as the percentage of transplanted teeth, still

present at the time of recall and still functioning in the patient’s mouth, not taking other

parameters into account.

The dissimilarity between studies could be explained by the difference in observation time

(45). It is also important to consider the difference in ‘success-criteria’. There are no fixed

success criteria (68).

The prognosis and success of a transplant depends on a number of influencing factors (54),

like donor tooth type (single rooted teeth have the best prognosis due to less difficult surgical

removal), developmental stage of the donor tooth (Cfr. fig.2), age of the patient (due to

reflection of the relation between age and root development), extraoral storage of the graft

(risk of dehydratation and mechanical damage to the PDL), experience of the surgeon and

oral hygiene.

17

IV.      Smile  aesthe=cs

1. Smile design

___________________________________________________________________________

Periodontal health and aesthetic appearance became more and more emphasized in

orthodontics and other dental disciplines (70). Modern dentistry requires a harmonious

balance between occlusion and soft tissues. The dentist is striving for the most attractive

smile.

Many parameters are involved, creating a beautiful smile. The smile design can be divided in

four parts: facial aesthetics, gingival aesthetics, microaesthetics and macroaesthetics (71).

1.1 FACIAL AESTHETICS

Based on a review of the literature, Frese et al. (72) concluded that symmetry is a very

important factor in facial attractiveness. For the determination of the facial midline, Morley

and co-workers (71) suggested to use two reference points because eyes, nose and chin can be

deceptive: nasion (the midpoint between the eyebrows), and the base of the philtrum. The

facial midline should coincide with the maxillary and mandibular incisor midline as much as

possible. A discrepancy of 1,5 to 2 mm is acceptable, and gives the dentition a natural

appearance (73).

1.2 GINGIVAL AESTHETICS

Gingival aesthetics should not be underestimated in the smile design.

Factors that influence gingival aesthetics are: gingival morphology and spatial conditions,

periodontal biotype, shape, texture and color of the soft tissue (74).

The presence of a papilla between the incisors is a key aesthetic factor as well. Furthermore,

gingival margin discrepancies should be avoided; the gingival margin of the 2 central incisors

should be at the same level. This level should be more apically than the gingival margin of the

lateral incisors and at the same level as the canines (75).

18

1.3 MICROAESTHETICS

Microsaesthetics involves all the elements dealing with the tooth itself. With regard to microaesthetics, the anatomy of the anterior teeth is of great importance. According to Wolfart and colleagues (76), most dentists prefer a width to height ratio of 75 to 80. Also, incisal translucency, lobe development etc. play a role in the aesthetic outcome. In 1978, Levin (77) introduced the golden proportion for the anterior tooth region. Nowadays, authors believe that the golden proportions are not always superior (78). Another key factor in microaesthetics is the tooth position in the dental arch. In a frontal view, axial inclination of anterior teeth is slightly progressive as the teeth progress away from the midline (73)(Fig. 3). Wolfart et al. (76) investigated aesthetics with regard to tooth inclination, and concluded that incisors with ideal tooth axes are rated the most attractive. Mesial or distal angulations of more than 10 degrees are rated least attractive.

Figure 3. (73) Maxillary anterior teeth with adequate axial inclinations.

1.4 MACROAESTHETICS

Macroaesthetics takes groups of teeth and the relationship between previous aspects into

consideration. Concerning macroaesthetics, the smile line is an important factor. The smile

line is the line that connects the incisal margins of the maxillary incisors with the canines or

premolars (73). When the incisal edges of the maxillary central incisors appear below the tips

of the canines, the smile line is convex (Fig. 4,a). When they appear above the tips of the

canines, the smile line is concave. This is called a ‘reverse smile line’ (Fig. 4,b). According to

Morley et al. (71), a convex smile line is in general more aesthetic than a concave smile line.

On the other hand, a straight smile line in males is also acceptable.

A second aspect in the evaluation of macroaesthetics is the presence of buccal corridors.

A buccal corridor is the space between the buccal surface of the posterior teeth and the lip

corners, while smiling. Janson and colleagues (79) concluded in their systematic review that

there is no agreement in the literature concerning buccal corridors. Some found no agreement,

where others concluded that small buccal corridors are more attractive.

19

Also, the size of incisal embrasures can influence the smile aesthetics. The incisal embrasure

can be defined as the space existing on the incisal aspect of the interproximal contact area

between adjacent anterior teeth. In normal dentitions, the size and volume of the incisal

embrasures between teeth increases as the teeth are positioned posteriorly (71)(Fig. 4,c).

A last important factor concerning macroaesthetics, is the tooth and gingival exposure. This is

the amount of tooth structure or gingiva that appears during smile. Too much or too little

exposure can impede a beautiful smile. A normal maxillary central incisor exposure is 3/4 of

the clinical crown to 2 mm of gingival exposure (73). Nevertheless, the maxillary incisal edge

reveal shrinks with age, while mandibular incisor exposure increases (71).

Figure 4 (73) a. Convex smile line b. Reverse smile line c. Incisal embrasures

One can conclude that smile design is a gathering of various factors. Although there is an

agreement between authors concerning which characteristics create the most perfect smiles, it

should not be forgotten that each patient is unique, with their own age characteristics,

personality, specificity and expectations. Furthermore, lay people can have different

preferences regarding frontal dentofacial aesthetics compared to their clinician (80).

20

2. Assessment of the smile aesthetics

__________________________________________________________________________

In modern dentistry focus has shifted from survival of tooth restorations, dental implants,... to

the quality of restoration/implant survival. Nowadays, dentists are more and more concerned

with the aesthetic outcome of their restorations. For the evaluation of dental aesthetics, a

distinction must be made between subjective and objective methods.

2.1 SUBJECTIVE METHODS

The opinion of the patient is very important in determining the treatment success. Subjective

rating methods, for example questionnaires, were developed to rate the satisfaction of the

patients.

2.2 OBJECTIVE METHODS

However, subjective assessment can’t evaluate any potential errors in restorations. As a

consequence, objective methods by professional examiners based on fixed criteria were

necessary. In the last 30 years, various articles, introducing objective rating systems were

published (81-84). Within the context of a rise in aesthetic awareness, not only

prosthodontists, but also periodontists searched for a good scoring index for objective implant

assessment. In 2005, Meijer and colleagues (85) published a new rating system for the

assessment of the crown on single-tooth implants: the Implant Crown Aesthetic index (ICA).

This new index drew attention of many researches and practitioners, as the index takes not

only parameters evaluating the implant crown, but also the peri-implant mucosa into account.

Later on, however, Gehrke et al. (74) found the validity and reproducibility of the ICA index

to be defective.

In the same year, Testori and colleagues (86) proposed a new index of aesthetic assessment.

Points up to 9 are given to parameters as: presence and stability of the mesiodistal papilla,

buccopalatal alveolar ridge stability, structure and color of peri-implant mucosa and gingival

contour.

Fürhauser et al. (87) presented a rating system for the aesthetic evaluation of the soft tissue

around single-implant restorations: The Pink Esthetic Score (PES).

21

1. Mesial Papilla

2. Distal papilla

3. Midfacial level

4. Midfacial contour

5. Alveolar process deficiency

6. Soft tissue colour

7. Soft tissue texture

Figure 5. (87) Pink Esthetic Score by Fürhauser et al.

This index includes 7 variables (Fig. 5). The contralateral tooth is used as a reference, and

points are given to each item respectively. On each item 0, 1 or 2 points can be assigned,

representing major, minor or no discrepancies compared to the contralateral tooth. The highest

score for the PES is 14. Nowadays, the PES is considered a useful and objective rating

method. However, the assessment of the implant crown is not included in this index (74).

In 2009, Belser et al. (88) defined a new index for objective outcome assessment. In this

index, the author modified the PES and completed it with an implant restoration index: the

WES (White Esthetic Score). In contrast to the proposal of Fürhauser in 2005, Belser only

included 5 of the 7 parameters of the PES: mesial papilla, distal papilla, curvature of the facial

mucosa, level of the facial mucosa and root convexity / soft tissue colour and texture at the

facial aspect of the implant site. These 5 items are also given a score of 0, 1, or 2, taking the

contralateral tooth as a reference. 0 representing major discrepancies, 1 minor, and 2 no

discrepancies.

The WES focuses on the implant restoration itself, and is also based on 5 parameters: tooth

form, outline/volume of the crown, colour, surface texture, translucency / characterization.

Scoring of the WES is comparable to the PES; where the contralateral tooth is also used as a

reference. On each item 0, 1 or 2 points can be assigned representing major, minor or no

discrepancies. The highest score for the WES is 10.

22

Figure 6. (88) White Esthetic Score (left) and Pink Esthetic Score (right) by Belser et al.

23

                                                                                                                                                                                                                                                                                                                                                                         

                               

                                       Chapter  II  

     Aesthe0c  outcome  of  autotransplanted  premolars  replacing                                      maxillary  incisors.  A  retrospec0ve  study

________________________________________________________

24

                     

                                                                                                                                                   I.     Research  of  the  literature

The same filters, publication date from 1990/01/01 to 2015/02/31 and English literature were

used in all the databases.

A first selection was made, based on the elimination of case reports, animal- and in-vitro

studies. Furthermore, after reading the abstracts, a second selection was made. This selection

was based on the presence of a subjective or objective rating method of the aesthetics of the

transplants, or the presence of succes-criteria concerning the aesthetic result of the

transplantations.

1. Medline___________________________________________________________________________

Results Selection 1 selection 2

#1

#2

#3

#4

#5

#6

#7

#8

#9

#10

“Tooth transplantation” [Mesh] 0 / /

“Tooth transpl*” OR “transpl* of teeth” 3076 2135 /

“Esthetic*” OR “Aesthetic*” 23339 18705 /

“Success” OR “Success rate” 155451 150563 /

“Tooth survival” OR “Survival rate” OR “life*” 924256 891454 /

#2 AND #3 360 168 1

#2 AND #4 267 203 2

#2 AND #5 179 158 2

#2 AND #3 AND #4 41 23 0

#2 AND #3 AND #5 12 9 0

Table 3. Search results, Medline.

After discarding all the duplicates, three articles were finally selected in Medline:

Czowhrowska E, Stenvik A, Zachrisson B. The esthetic outcome of autotransplanted

premolars replacing maxillary incisors. Dent Traumatol. 2002; 18: 237-245. (89)

25

Czowhrowska E, Stenvik A, Bjercke B, Zachrisson B. Outcome of tooth transplantation:

Survival and success rates 17-41 years posttreatment. Am J Orthod Dentofacial Orthoped.

2002;121:110-9. (66)

Plakwicz P, Woitowicz A, Czochrowska E. Survival and success rates of autotransplanted

premolars: A prospective study of the protocol of developing teeth. Am J Orthod Dentofacial

Orthop. 2013; 44:229-37 (69)

2. Web of Science

___________________________________________________________________________

Results Selection 1 Selection 2

#1 Topic=(Tooth Transplantation) refined by: Web of science categories= (Dentistry

Oral Surgery Medicine)

51 39 1

#2 Topic=(Aesthetic) OR Topic=(Esthet*) refined by: Web of science categories= (Dentistry Oral

Surgery Medicine)

665 551 /

#3 Topic=(Succes rate) OR Topic=(Succes)refined by: Web of science categories= (Dentistry Oral

Surgery Medicine)

520 465 /

#4 #1 AND #2 20 11 1#5 #1 AND #3 22 15 /

Table 4. Search results ,Web of science.

The final selection in the Web of science consisted of two articles:

Czowhrowska E, Stenvik A, Zachrisson B. The esthetic outcome of autotransplanted

premolars replacing maxillary incisors. Dent Traumatol. 2002; 18: 237-245.(89)

Plakwicz P, Woitowicz A, Czochrowska E. Survival and success rates of autotransplanted

premolars: A prospective study of the protocol of developing teeth. Am J Orthod Dentofacial

Orthop. 2013; 44:229-37 (69)

26

3. Cochrane Library

___________________________________________________________________________

Cochrane Reviews

Selection 1 Selection 2

#1 “Tooth Transplantation” 4 4 0#2 Aesthetic* OR esthetic* AND Dental 24 24 0

Table 5. Search results, Cochrane Library.

In the Cochrane Library, no systematic reviews were selected.

All references of the selected articles were checked, and based on the criteria, some extra

articles were included:

Zachrisson B, Stenvik A, Haanaes H. Management of missing maxillary anterior teeth with

emphasis on autotransplantation. Am J Orthod Dentofacial Orthop. 2004;126:284-8 (43)

Czochrowska E, Stenvik A, Album B, Zachrisson B. Autotransplantation of premolars to

replace maxillary incisors: A comparison with natural incisors. Am J Orthod Dentofacial

Orthop. 2000; 118: 592-600 (90)

Table 6 summarizes the selected articles:

# pt # transplteeth

observation time

survival rate%

succes rate%

professional aesthetic

assesment

scoring pt satisfaction

1. Czochrowska et al. 2002 (89)

22 22 3y, 11m 100 95 Yes Yes

2. Czochrowska et al. 2002 (66)

25 30 26y, 4m 90 79 / Yes

3. Czochrowska et al. 2000 (91)

40 45 4,0y 100 / only soft tissue /

4. Plakwicz et al. 2013 (69)

19 23 2y, 11m 100 91,3 / Yes

5. Zachrisson et al 2004 (43)

/ / / / / / /

Table 6. Summary of the selected articles (pt= patient; y= years; m=months; transpl= transplanted).

27

From the selected articles, only the first (89) and the third (91) one have used some kind of

objective method to rate the transplant’s aesthetics. Hence, the third article only scores the

soft tissue without assessing the hard tissue. The first article by Czochrowska et al (2002) (89)

evaluates both tissues by assessing 8 features. The features variate from colour of the tooth,

soft tissue surrounding the tooth to tooth morphology and position. All measurements were

given numerical scores by defining cut-off points. The sum of the scores was transformed to

an aesthetic category.

One can conclude that the current litterature contains little evidence concerning the aesthetic

outcome of premolar transplantations to the incisor region, especially using an objective

scoring system. The objectives of this study were, therefore, to evaluate the aesthetic outcome

of transplanted premolars to the incisor region with both an objective scoring method with

well defined criteria, as well as an subjective scoring method, rating the patient’s opinion

about the results.

                                            II.   Aim

The literature contains little comprehensive studies concerning the aesthetic results of

premolar autotransplantation. The aim of this study was to evaluate the aesthetic outcome of

transplanted premolars to the maxillary anterior region. The null hypothesis stated that there

was no difference between the aesthetic outcome of transplanted premolars and their

contralateral tooth, using an objective scoring system. The satisfaction of the patient regarding

tooth transplantation was also rated.

28

                                                        III.    Material  and  Methods

1. Subjects_____________________________________________________________________________________________________

The sample of this study consisted of a group of patients, who have had a premolar

transplantation to the maxillary anterior region. Material was obtained from 4 centres:

University hospital of Ghent (Belgium), ZOL hospital in Genk (Belgium), Clinic for

Periodontics Rotterdam (The Netherlands) and University of Warsaw (Poland).

The inclusion criteria for the transplantation patients are:

- One premolar transplant to the maxillary incisor region (12-22)

- Non-restored contralateral tooth

- Natural teeth present both mesial and distal to the transplant

- Restorative procedure: All transplanted teeth are restored to maxillary central or lateral

incisor morphology by a composite resin or laminate veneer build-up.

- No orthodontic appliance present on the transplanted tooth, neighbouring and

contralateral teeth

The subjects fulfilling the criteria were contacted by email and phone. The material was

collected in the clinic where the patient was treated. All patients were asked to sign an

informed consent. An approval was given for this project by the ethical committee of Ghent

and Genk (B670201316476) (see appendix I) and the Medical University of Warsaw (AKBE/

85/14).

29

2. Data collection

___________________________________________________________________________

2.1 INTRA-ORAL PICTURES

Intra-oral pictures (frontal and occlusal photograph) were taken from all patients, using a

black contrast plate (Fig. 7). The photographs show only the maxillary arch and the

surrounding gums as much as possible.

Figure 7. Frontal and occlusal photograph of the dental arch.

2.2 GINGIVAL THICKNESS

The gingival thickness was evaluated by placing a periodontal probe into the labial buccal

sulcus of the contralateral incisor. Each patient was categorised into a ‘thick’, ‘thin’ or

‘doubt’ group. The ginigva was categorised as thin if the outline of the periodontal probe

could be seen through the gingiva, thick if the outline could not be seen, and doubt if it was

unclear, as described by De Rouck and colleagues (92).

Figure 8. Evaluation of gingival thickness by placing a periodontal probe.

30

2.3 PLAQUE AND GINGIVAL INDEX

The presence of inflammation in the marginal portion of the gingiva is usually assessed using

a periodontal probe, according to the principles of Loë et al. (93). In this study a symplified

variant of the Gingival bleeding Index (94) and the Plaque Index (95) was used. Bleeding

from the gingival margin within 15 sec after probing and the presence of visible plaque was

scored as ‘1’. Absence of bleeding of visible plaque scored ‘0’. The Plaque and Gingivitis

index was measured at the labial side of the transplants.

2.4 ADDITIONAL INFORMATION

Following data were additionally collected, because they could influence the aesthetic result:

- Age of the patient

- Age at the time of transplantation

- Type of restoration (laminate veneer or resin build-up)

- Gender

- Donor tooth

- Position of the donor tooth in the recipient area (rotated or not rotated)

- Orthodontic treatment after transplantation

- Surgeon (By whom/where was the transplantation performed)

- Lifespan of the restoration

- Soft tissue manipulation

- Position of the transplant (central or lateral incisor)

- Mesio-distal width: the mesio-distal width of the contralateral incisor was measured,

in order to calibrate the pictures on the computer.

31

3. Aesthetic evaluation

__________________________________________________________________________

Figure  9. Guide for the use of PES and WES (88).

The Pink Esthetic Score (PES) by Fürhauser et al. (87) and the White Esthetic Score (WES)

by Belser and colleagues (88) were used to evaluate the aesthetic outcome of the transplants

on the intra-oral pictures. These scoring systems are frequently used in the aesthetic

evaluation of dental implants. (See figure 9) In this rating method, the transplanted tooth is

compared to its contralateral tooth.

The scoring was done twice by the same observer to measure the intra-observer reliability.

The overall aesthetic outcome was assessed by combining the PES and WES. As described by

Cosyn et al. (96), cases can be considered as an aesthetic failure when PES and/or WES <6,

aesthetically acceptable when PES or WES are ≥6 and <9, and as an (almost) perfect result if

PES and WES were ≥9.

32

4. Patient’s aesthetic satisfaction__________________________________________________________________________________

The patients were asked to express their perception regarding tooth transplantation using a

questionnaire with a visual analogue scale, adapted from Czochrowska et al. (66). Two

additional questions were added (Question 9 and 10) (See appendix II).

33

                       IV  Sta=s=cal  tests

To determine which statistical tests had to be performed, all parameters were put to a test of

normality: The Shapiro-Wilk test. If the parameters scored lower than 0.05, the values were

not distributed according to the Gaussian ‘bell curve’. In that case, a non-parametric test

should be used. To find differences in the outcome (PES and WES), the non-parametric

Mann-Whitney U test and the Kruskal-Wallis test were used. The Spearman test was used for

evaluation of a possible correlation between two variables. The significance level was set to

0.005 (5%).

1. Error of method; Intra-observer reliability

___________________________________________________________________________

For analyzing intra-observer reliability 15 patients were rescored 4 weeks after the first

recording by the same clinician (ST).

1.1 DAHLBERG’S FORMULA

Dahlberg’s formula was used to determine the random error (RE) of scoring the PES and

WES. The Dahlberg formula is defined as:

√  (Σd2/2n)       d= the difference between the first and the second scoring

n= the sample size which was re-measuredThe RE for the WES= 1.32The RE for the PES= 0.75

1.2 INTRACLASS CORRELATION

The intraclass Correlation Coefficient (ICC) reflects the degree of reproducibility or

consistency of the measurements. The ICC was measured for PES and WES:

ICC for PES= 0.93ICC for WES=0.85

According to Fleis et al. (97), it can be concluded that both PES and WES have excellent

reliability.

34

                      V.  Results

1. Study Sample

_________________________________________________________________

After searching the databases of the different centres, 45 patients met the selection criteria and

were contacted. Two patients lost the transplanted tooth in the past. Eleven patients could not

be contacted or motivated for participation. The remaining 32 patients came in for clinical

examination and data collection. (17 patients from University Hospital Ghent, 3 patients from

ZOL (Ziekenhuis Oost-Limburg) hospital in Genk, 8 patients from University of Warsaw and

4 patients from a private dental practice in Rotterdam (Figure 10). The mean age of the

patients was 19 years (range 11-36). The mean observation time was 7 years (range 1-23).

The mean age of the restoration was 4.7 years (range 1-12) (Table 7).

Figure  10. Distribu(on  of  included  pa(ents.

35

TABLE  1:  DEMOGRAPHICS

PATIENTS Number %Total

Ghent Genk Rotterdam Warsaw

32

17348

Female/Male 13/19 40.6/59.3TRANSPLANTS

Donor tooth 15 25 45 35 14 44 24 34

149521100

43.728.115.66.23.13.10.00.0

Rotation Yes No

275

84.315.6

Site Central incisor Lateral incisor

293

90.69.3

Orthodontic treatment Yes No

275

84.315.6

Restoration Resin build-up Veneer

293

90.69.4

Biotype Thick Thin Doubt

2372

71.821.86.9

Plaque Index No Plaque Plaque

2111

65.634.3

Gingival Bleeding Index No bleeding bleeding

1913

59.340.6

Table  7.  Demographics.

36

2. Aesthetic evaluation

___________________________________________________________________________

Thirty-four per cent (n=11) were aesthetic failures (PES and/or WES < 6). Eighty-one per

cent of these failures was considered unfavourable because of a WES < 6 (n=9), whereas only

two cases showed a disappointing PES (PES < 6). The remainder (56%, 18 cases)

demonstrated acceptable aesthetics. Three cases (9%) showed a (almost) perfect outcome

(PES and WES ≥ 9) (Tables 8,9 / Figures 11,12). The presence of a mesial and distal papilla

(PES) was overall most easy to satisfy, whereas tooth colour, translucency/characterization

and surface texture (WES) were most difficult. A statistically significant difference was found

between patients with a porcelain veneer and the WES. Patients with a veneer scored

significantly higher for the WES (p=0.026). However, the clinical significance of this

outcome should be handled with caution, because of the very small number of transplants

with veneers in this study population (Table 7).

A.

B.

C.

Figure  11.  Examples  of  unfavorable  aesthe(cs  (A),  acceptable  aesthe(cs  (B)  and  an  almost  perfect  result  (C).

37

Figure  12.  Outcome  of  PES  and  WES.

PES  <6 PES  ≥  6  and  <9 PES  ≥9 WES  <6 WES  ≥  6  and  <9 WES  ≥9

Number  of  patients

2 18 12 9 19 4

 %    6.2 56.2 37.5 28.1 59.3 12.5Table  8.  Overall  aesthe(c  outcome.

38

PATIENT          

           PEStotal          

         WEStotal1   3 72 8 73 6 54 7 75 7 46 9 77 9 58 8 69 9 410 6 611 8 412 8 313 10 614 8 415 10 816 6 617 6 518 9 719 6 720 6 821 9 622 7 623 9 724 8 625 9 926 9 927 5 628 8 429 9 630 7 931 6 632 9 9

Table  9.  Results  for  PES  and  WES  (≥ 9:  green  /  <6:  red).

39

3. Additional parameters

___________________________________________________________________________

No statistically significant difference was found between the presence of plaque or bleeding

by probing and the PES or WES score. There was no difference in PES and WES when the

donor tooth came from the upper jaw, compared with the lower jaw. The statistical tests were

conducted for all donor teeth separately and for the upper teeth together compared to the

lower teeth together. No significant difference was found for PES and WES between the

different gingival biotypes, whether the patient had orthodontic treatment or whether the

transplant was rotated in the alveolar recipient site (Table 10). No statistically significant

difference was found for the plaque Index and the WES, but the difference was small. (p=

0.055).

Parameter Statistical test P value (PES) P-value (WES)

Biotype Kruskal- wallis 0.44 0.61

Donor tooth Kruskal-Wallis 0.52 0.97

rotation Mann-Withney U 0.136 0.122

Orthodontic treatment Mann-Withney U 0.67 0.200

Plaque Index Mann-Withney U 0.81 0.055

bleeding Index Mann –Withney U 0.40 0.102

Table  10.  P-­‐values  of  the  different  parameters  for  PES  and  WES.

4. Patient’s satisfaction

___________________________________________________________________________

Figure 13 shows the results with means and ranges of the 100 mm visual analogue scale. A

threshold was set on 25%: When the mean was less than 2.5, the treatment and results were

assumed to be good. Most patients found it rather easy to decide to do the autotransplantation

(Question 3) (mean 1.7). In general, the patients experienced the transplantation as a quite

40

uncomfortable procedure. (Question 1 and 2) (mean 4.2 and 3.5), and they tended to know

which tooth was moved to which position (Question 4 and 5) ( mean 1.4 and 2.1). For most

patients, it did not take extra effort to maintain the transplanted tooth (Question 8) (mean 1.5).

In general, the aesthetic outcome of the transplant was found to be a bit different as the other

teeth (Question 6) (mean 4.8). Although, most patients where rather satisfied with the

aesthetic outcome of the surrounding gums and crown (Question 9 and 10) (means 1.8). Also,

in the majority of the cases, patients were satisfied with the position of the transplanted tooth

in the dental arch (Question 7) (mean 1.4).

The spearman test was used to find a correlation between the answers (Table 11). A

statistically significant correlation was found between the answers to question 2 and question

6 (rs=0.47, p=0.008) and question 8 and question 6 (rs= 0.71, p=0.001). In other words,

patients who experienced more pain and discomfort during the transplantation found the

aesthetic outcome of the transplanted tooth quite different compared with the rest of their

teeth. This feeling was also present for patients for whom the transplanted tooth required

more effort to maintain compared with the other teeth. A signifiant correlation was found

between the answers to question 9 and 6 (rs= 0.68, p<0.001) and question 10 and 6 (rs= 0.80,

p<0.001). Summarized, patients who were less satisfied with the aesthetic outcome of the

crown or the gums surrounding the transplant were less satisfied with the aesthetic outcome of

the transplanted tooth compared with the other teeth. Even more, a statistically significant

correlation was found between question 9 and 10 (rs=0.70, p<0.001). Patients who did not like

the aesthetics of the crown, were not satisfied with the results of the soft tissue either. On the

contrary, no correlation was found between question 9 (satisfaction of the gums) and PES and

question 10 (satisfaction of the crown) and WES.

Question 6 Question 10 PES WES

Question 2rs= 0.47p= 0.008

Question 8rs= 0.71p= 0.001

Question 9rs= 0.68p< 0.001

rs= 0.70p<0.001

rs= -0.16p= 0.413

Question 10rs= 0.80p<0.001

rs=-0.20p= 0.311

Table 11. Correlations found in the Questionnaire with their p-value (p) and correlation coefficient (rs).

41

42

Figure  13.  Pa(ent's   response   to  the  100  mm  visual  analogue  scale.  The  values  represent  the  means  

and  ranges.

                       

43

                          VI.    Discussion

The survival rate in the present study was high (95%) (The transplanted tooth was lost in 2

out of 45 cases), and comparable with other studies (48, 50, 52, 54, 66). In the past, tooth

survival was the main focus in literature. The survival rate is defined as the percentage of

transplanted teeth still present at the time of recall and still functioning in the patients mouth,

not taking other parameters into account.

Nevertheless, also the success rate of the transplantations is of importance. The success rate

can be defined as the percentage of transplanted teeth, meeting certain criteria. Many success

criteria have been described: (root length, absence of resorption, periodontally healthy

situation,...) (54, 68). However, the aesthetic outcome of the transplantation was not often

included. Although, creating an optimal aesthetic result is equally important in contemporary

dentistry. Therefore, the aim of the present study was to evaluate the aesthetic outcome of

transplanted premolars to the maxillary anterior region.

1. Aesthetic evaluation

___________________________________________________________________________

An aesthetic scoring system for single tooth implants was used in the current study. The

question rises if this aesthetic scale is well applicable for transplanted teeth. No well-defined

and satisfying aesthetic scoring systems for autotransplantations have been described in the

past. Therefore, a more extensive search was necessary in a broader part of dentistry to find a

well applicable scoring system. The PES and WES were chosen. The major advantage of this

aesthetic scoring system is the evaluation of both the crown of the tooth and the surrounding

soft tissues. Both are equally important in evaluating aesthetics of a transplanted tooth. In

both PES and WES different parameters are taken into account which might influence the

aesthetic outcome. These parameters are no different for transplants as they are for dental

implants.

Patients responded favourably regarding the treatment outcome. Kallu et al. (53) investigated

the aesthetic outcome of autotransplanted teeth with resin build-ups and found an overall

44

satisfaction of the patients as well.

These results were confirmed in the studies of Czochroswka et al. (66) and Plakwicz et al.

(69): most patients were satisfied with the outcome of the transplant and the opinion of the

patients matched the professional scoring for most parameters. In this study, a statistically

significant correlation was found between question 9 and question 10. Patients who did not

like the results of the crown, did not like the results of the soft tissue as well. One could ask if

these patients were just more critical towards the treatment outcome.

In another study of Czochrowska et al. (89), 22 autotransplanted premolars were compared

with their contralateral, natural incisor. Tooth colour, soft tissue appearance and tooth

morphology and position were evaluated. Only a minor part of the cases (25%) were

considered as aesthetically unacceptable. Colour and gingival width were the parameters with

the highest disparity with the contralateral incisors. There was a tendency to have better

aesthetic results with lower premolars as donor teeth, compared with upper premolars, but this

was not statistically significant. Compared to Czochrowska et al., our results were less

optimistic (34% were aesthetic failures). Especially, tooth colour, translucency/

characterisation and surface texture showed disappointing results. Another article of

Czochrowska et al. (91), published in 2000, compared the transplanted teeth with natural

incisors within the same patient. Clinical parameters as tooth moblity, plaque, gingivitis,

pocket depth and percussion were evaluated, as well as radiographic parameters as pulp

obliteration, root length and crown-root ratio. For the assessment of the interproximal

papillae, a scoring system for dental implants was used. This index measures the papilla from

a reference line through the highest curvature of the buccal gingiva of the transplant and the

adjacent tooth. Comparable with the current study, Czochrowska et al. found well preserved

interproximal gingival papillae. They also found increased mobility and more plaque in some

of the transplanted premolars.

2. Type of restoration

___________________________________________________________________________

In this study, a statistically significant difference was found between WES and laminate

veneer. Patients with laminate veneers tend to have higher WES scores. Nevertheless the

clinical significance of this outcome should be handled with caution, because of the very

small amount of veneers in this study population. In most cases, the transplanted tooth was

45

build-up with a composite resin. With this restorative material, it was difficult to achieve

enough width along the gingival margin. In these cases, the build-up often had a triangular

shape. This can be avoided by rotating the transplanted tooth during surgery or by placing a

laminate veneer (43). Another disadvantage of a resin build-up is discolouration of the

composite after some time. This problem could also be avoided with a laminate veneer. As the

results for the WES were lower than those for the PES, a careful conclusion can be made that

resin-build ups of the premolar transplants to maxillary incisor morphology are a temporary

solution. Laminate veneers might be better to provide a more aesthetic result regarding tooth

form and colour. However, the skills of the treating dentist are of great importance. Also,

attention should be brought on the fact that laminate veneers can not be placed in a young

child, because of gradual eruption of the transplant during growth. Hence, a resin-build up can

be placed as a temporary solution, in anticipation of further growth. On the other hand,

laminate veneers are much more expensive than the resin alternative and therefore not an

option for every patient. Moreover, most patients were satisfied with the composite build-up.

3. Orthodontic treatment

___________________________________________________________________________

Most of the patients in the current study underwent an orthodontic treatment. The orthodontic

treatment could have influenced the aesthetic outcome in some way, because the transplant is

not always placed in the best position during surgery. The surgeon tries to find the best fit of

the tooth in the alveolus for optimal healing. However, this position is not always the best one

to have a good aesthetic result. The orthodontist can replace the transplant afterwards in a

position for an optimal build-up of the transplanted tooth. In this study no statistically

significant difference was found between orthodontic treatment and the aesthetic outcome of

the transplant. This is probably due to the small number of patients (15.6%) who did not have

any orthodontic treatment.

46

4. Gingival thickness

___________________________________________________________________________

It has been described in the literature, that gingival thickness or biotype plays an important

role in soft tissue aesthetics (98). In the past, gingival biotype has been characterised by

different factors; gingival width, gingival thickness, width of keratinzed gingiva, crown

dimensions, presence of papillae,...(99) .

Two types of gingival biotypes have been defined; A thick periodontal biotype is attributed to

a flat and firm mucogingival appearance. Also, these patients would have squarer teeth and

better interproximal papillae (99). On the other hand, a thin periodontal biotype is described

as a thin, scalloped mucogingival appearance with more triangular shaped teeth. These

patients would have a higher incidence of black triangles, recession and bone dehiscences

(99).

Several methods to define the gingival biotype of the patient have been described.

Most clinicians use visual assessment of the gingival biotype (98, 100). However, it has been

described that this visual subjective assessment is not always sufficiently reliable (100, 101).

Kan et al. (101), investigated 48 patients with a lost maxillary incisor. Before this tooth was

extracted, the gingival thickness was identified with visual assessment and with the

periodontal probe. After extraction of the incisor the gingival thickness was measured using a

calliper. The biotype was considered thin if it was ≤  1.0 mm and thick if it was > 1.0 mm. Kan

et al. concluded that assessment of the gingival biotype by using an periodontal probe was

more reliable compared to the visual assessment.

Recently, new methods for measuring soft tissue thickness have been described. One of these

methods is the ultrasonic determination of the thickness of mucosa. This device uses the pulse

echo principle: ultrasonic pulses are transmitted through the mucosa and the thickness of the

mucosa is determined by the timing of the echo received. This method produces valid and

reproducible results (102, 103). One could expect that patients categorised as ‘thin gingival

thickness’ would tend to have a lower PES. However, no statistically significant difference

was found between PES and gingival biotype in the current study.

47

5. Gingivitis and Plaque Index

___________________________________________________________________________

The presence of plaque has a direct influence on the presence of gingivitis. In most of these

patients, presence of gingivitis was due to a lack of oral hygiene. Another cause of gingivitis

were restorations with a bad fit of the resin-enamel border. In these cases, revision of the

restoration is necessary to obtain a healthy environment. Because of gingival swelling and

redness in cases of gingivitis, one could expect lower PES for parameters as ‘soft tissue

colour and texture’. However no significant difference between PES and gingival index was

found. On the other hand, Czochrowska et al. (91) found more plaque and bleeding in a few

transplanted premolars. Also, in the former study, a slightly increased pocket depth was seen,

probably due to gingivitis.

6. Limitations

___________________________________________________________________________

The current study showed limitations regarding the variability within the sample. Few patients

had porcelain veneers or did not undergo orthodontic treatment. Therefore, it is difficult to

make conclusions regarding these variables. Moreover, the sample size within each dental

centre is very small, so a comparison between these groups could not be made. In this sample,

not a single patient underwent a soft tissue manipulation. (e.g. gingivectomy). However, the

PES was quite good, so this might not be necessary in the future either. Additionally, all

patients were treated by different oral surgeons in all dental centres. However, all surgeons

were experienced with autotransplantation of premolars to the maxillary anterior region. Also,

all restorations were placed by different general dentists. Especially for anterior restorations,

experience and insight of the dentist is crucial for the final aesthetic result.

Attention should be brought upon the fact that the scoring was done twice by the same

observer and no extra observers were included. Also, the scoring was done by an orthodontist

and different outcomes could be expected by other dental groups. A periodontist might have

the tendency to score lower for the PES, because they are more critical regarding periodontal

health. A prosthetic dentist on the other hand might be more strict for the WES, and a layman 48

might be more forgiving for the different parameters.

Even though the aesthetic result of the transplants shows some drawbacks, one should

remember that the transplant preserves the alveolar bone in a young patient unlike a resin

bonded bridge. On the other hand, with the recent attention for the use of TAD’s (Temporary

Anchorage Device) in orthodontic treatment, orthodontic space closure is applicable in more

cases than it used to be. Czochrowska et al.(17) investigated the outcome of orthodontic space

closure with a missing maxillary central incisor. She found that certain aspects of the

recontoured incisor crown mismatched the control teeth. In these cases tooth morphology is

important to define the treatment of choice. However most patients were satisfied with the

treatment results. So, different aspects as malocclusion, tooth morphology, facial morphology,

etc. should be considered for making most the adequate treatment plan.

49

                          VII.    Conclusions

-­‐  Most transplanted premolars to the maxillary anterior region have acceptable aesthetics.

-­‐ A low WES was the main cause for transplants defined as ‘aesthetic failures’.

-­‐ A significantly higher WES was found for patients with porcelain veneers.

-­‐ Most of the patients were satisfied regarding the treatment outcome.

-­‐ Patients who did not like the results of the crown, did not like the results of the soft tissue

either, and may be more critical.

-­‐ Type of donor tooth, rotation of the transplant, orthodontic treatment and gingival thickness

did not influence the aesthetic outcome.

-­‐ These results should be handled with caution because of the small sample size of the

different groups.

The aesthetic outcome was in some way disappointing. This result was mainly due to a low

WES. Laminate veneers might be better to provide a more aesthetic result.

On the other hand, patients responded favourably regarding the treatment outcome.

                                         

50

                                                                      VIII.      Bibliography

1. Hedegard B, Stälhane I. A study of traumatized permanent teeth in children aged 7-15 years. Part 1. Swed Dent J. 1973;66:431-50.

2. Trope M. Clinical management of the avulsed tooth. Dent Clin North Am. 1995;39:93-112.

3. Emerich K, Wyszkowski J. Clinical practice. Dental trauma. Eur J Pediatr. 2010;169:1045-50.

4. Bastone E, Freer T, McNamara J. Epidemiology of dental trauma; A review of the literature. Australian Dental Journal. 2000;45(1):2-9.

5. Burden D. An investigation of the association between overjet size, lip coverage, and traumatic injury to maxillary incisors. Eur J Orthodont. 1995;17(5):13-7.

6. Besserman K. Frequency of maxillo-facial injuries in an hospital population of patients with epilepsy. Bull Nord Soc Dent Handicap. 1978;5(2-26).

7. Lalloo R. Risk factors for major injuries to the face and teeth. Dent traumatol. 2003;19:12-4.

8. Sabuncuoglu O, Taser H, Berkem M. Relationship between traumatic dental injuries and attention-deficit/hyperactivity disorder in children and adolescents: proposal of an explanatory model. Dent traumatol. 2005;21:249-53.

9. Tuli T, Hachl O, Rasse M, Kloss F, Gassner R. Dentoalveolar trauma. Analysis of 4763 patients with 6237 injuries in 10 years. Mund Kiefer Gesichtschir. 2005;9:324-9.

10. Farell A, Albert D, Kamila S. Peer influences and drug use among urban adolescents: Family structure and parent-adolescent relationship as protective factors. J of Consulting and Clinical Psychology. 1998;66:248-58.

11. Tallgren A. The continuing reduction of the residual alveolar ridges in complete denture wearers. A mixed longitudinal study covering 25 years. J of Prothetic Dentistry. 1972;27:120-32.

12. Gift H, Atchinson K. Oral health, health and health-related quality of life. Med Care. 1995;33:57-77.

13. Schroeder H. Handbook of Microscopic anatomy: The periodontium. Berlin: Springer Verlag; 1986.

14. Van der Weijden F, Dell'Acque F, Slot D. Alveolar bone dimensional changes of post extraction sockets in humans: a systematic review. J Clin Periodontol. 2009;36:1048-58.

15. Jahangivi L, Devlin H, Ting K, Niskimure I. Current perspectives in residual remodeling and its clinical implication: a review. J of Prothetic Dentistry. 1998;80:224-37.

16. Bartee B. Extraction site reconstruction for alveolar ridge preservation. Part II: Rationale and material selection. J of Oral Implantology. 2001;27:187-93.

17. Czochrowska E, Skaare AB, Stenvik A, Zacchrisson B. Outcome of orthodontic space closure with a missing maxillary central incisor. Am J orthod Denofacial Orthop. 2003;123:597-603.

18. Stenvik A, Zacchrisson B. Orthodontic closure and transplantation in the treatment of missing anterir teeth. An overview. J Endod Dent Traumatol. 1993;9:45-52.

51

19. Krassnig M, Fickl S. Congenitally missing lateral incisors- A Comparison Between Restorative, Implant, and orthodontic approaches. Dent Clin North Am. 2011;55:283-99.

20. Rosa M, Zacchrisson B. Integrating space closure and esthetic dentistry in patients with missing maxillary lateral incisors. JCO. 2007;16(9):563-73.

21. Armbruster P, Gardiner D, Whitley J, Flerra J. The congenitally missing maxillary lateral incisor. Part 1: Esthetic judgment of treatment options. World J Orthod. 2005;2005(6):369-75.

22. Zacchrisson B. Improving orthodontic results in cases with maxillary incisors missing. Am J orthod. 1978;73(3):274-89.

23. Armbruster P, Gardiner D, Whitley J, Flerra J. The congenitally missing maxillary lateral incisor. Part 2: Assessing Dentists' preferences for treatment. World J Orthod. 2005;6:376-81.

24. Nordquist G, McNeill W. Orthodontic vs. Restorative treatment of the congenitally absent lateral incisor - Longterm periodontal and occlusal evaluation. J Periodont. 1975;46(3):139-43.

25. Zacchrisson B, Rosa M, Toreskog S. Congenitally missing maxillary lateral incisors: Canine substitution. Point. Am J orthod Denofacial Orthop. 2011;139(4):434-45.

26. Brough E, Donaldson AN, Naini F. Canine substitution for missing maxillary lateral incisors: The influence of canine morphology, size, and shape on perceptions of smile attractiveness. Am J orthod Denofacial Orthop. 2012;138(705):705.e1-.e9.

27. Kokich V, Crabill K. Managing the patient with missing or malformed maxillary central incisors. Am J orthod Denofacial Orthop. 2006;129:55-63.

28. Rosa M, Zacchrisson B. The space-closure alternative for missing maxillary lateral incisors: An update. JCO. 2010;44(9):540-9.

29. Robertson S, Mohlin B. The congenitally missing upper lateral incisor. A retrospective study of orthodontic space closure versus restaurative treatment. Eur J Orthodont. 2000;22:697-710.

30. Priest G. Single-tooth implants and their role in preserving remaining teeth: a 10-year survival study. Int J Oral Maxillofac Impl. 1999;14(2):181-8.

31. Thilander B, Odman J, Jemt T. Single implants in the upper incisor region and their relationship te the adjacent teeth. An 8-year follow-up study. Clin Oral Implants Res. 1999;10:346)55.

32. Benic G, Wolleb K, Sancho-puchades M, Hämmerle C. Systematic review of parameters and methods for the professional assessment of aesthetics in dental implant research. J Clin Periodontol. 2012;39(12):160-92.

33. Dierens M, De Bruecker E, Vandeweghe S, Kisch J, De Bruyn H, Cosyn J. Alteration in soft tissue levels and aesthetics over a 16-22 year period following single implant treatment in periodontally-healthy patients: a retrospective case series. J Clin Periodontol. 2013;40:311-8.

34. Jemt T, Ahlberg G, Bondevik O. Changes of anterior clinical crown height in patients provided with single-implant restorations after more than 15 years of follow-up. Int J Prosthodont. 2006;19:455-61.

35. Oesterle L, Cronin R, Ranly M. Maxillary implants and the growing patient. Int J Oral Maxillofac Impl. 1993;8:377-87.

36. Nivedita M, Ramesh C, Brajesh PA, Nagaraj E, Poornima M. Dental implants in children and adolescents: A literature review. J Oral Implantol. 2012:ahead of print.

52

37. Thilander B, Ödman J, Lekholm U. Orthodontic aspects of the use of oral implants in adolescents: a 10 year follow-up study. Eur J Orthodont. 2001;23:715-31.

38. Olsen T, Kokich V. Postorthodontic root approximation after opening space for maxillary lateral incisor implants. Am J orthod Denofacial Orthop. 2010;137:158.e1-.e8.

39. Barber M, Preston A. An Update on Resin-Bonded Bridges. Eur J Prothodont Rest Dent. 2008;16(1):2-9.

40. Wyatt CCL. Resin-Bonded Fixed Partial Dentures: What's New? JCDA. 2007;73(10):933-8.

41. atkinson K. Histopathological and immunological aspects of tooth transplantation. J of oral Pathology. 1978;7:43-61.

42. kristerson L, Lagerström L. Autotransplantation of teeth in cases with agenesis or traumatic loss of maxillary incisors. Eur J Orthodont. 1991;13:486-92.

43. Zacchrisson B, Stenvik A, Haanaes H. Managment of missing maxillary anterior teeth with emphasis on autotransplantation. Am J orthod Dentofacial Orthop. 2004;126:284-8.

44. Mendes RA, Roncha G. Mandibular third molar autotransplantation-literature review with clinical cases. J Can Dent Assoc. 2004;70:761-6.

45. Andreasen J, Schwartz O, Kofoed T, Daugaard-Jensen J. Transplantation of premolars as an approach for replacing avulsed teeth. Pediatr Dent. 2009;31:129-32.

46. Slagvolds O, Bjercke B. Indications for autotransplantation in cases of missing premolars. Am J orthod. 1978;74(3):241-57.

47. Lownie J. Autotrasplantation of teeth; A review of current thoughts. Int J Orthod. 1987;25(3-4):4-7.

48. Andreasen J, Paulsen H, Yu Z, Bayer T, Schwartz O. A long-term study of 370 autotransplanted premolars. Part II. Tooth survival and pulp healing subsequent to transplantation. Eur J Orthodont. 1990;12:14-24.

49. Moorrees C, Fanning E, Hunt E. Age Variation of Formation Stages for Ten Permanent Teeth. J Dent Res. 1963;42:1490-502.

50. kristerson L. Autotransplantation of human premolars, a clinical and radiographical study of 100 teeth. Int J Oral Surg. 1985;14:200-13.

51. Thomas S, Turner S, Sandy J. Autotransplantation of teeth: Is there a role? British journal of orthodontics. 1998;25:275-82.

52. jonsson S, Sigurdsson T. Autotransplantation of premolars to premolar sites. A long-term follow-up study of 40 consecutive patients. Am J orthod Dentofacial Orthop. 2004;125:668-75.

53. Kallu R, Vinckier F, Politis C, S M, G W. Tooth transplantations: a retrospective study. Int J Oral Maxillofac surg. 2005;34:745-55.

54. Schwartz O, Bergmann P, Klausen B. Autotransplantation of human teeth. A life-table analysis of prognostic factors. Int J Oral Surg. 1985;14:245-58.

55. Paulsen H, Andreasen J, Schwartz O. Pulp and periodontal healing, root development and root resorption subsequent to transplantation and orthodontic rotation: A long-term study of autotransplanted premolars. Am J orthod Dentofacial Orthop. 1995;108:630-40.

56. Andreasen J, kristerson L. The effect of limited drying or removal of the periodontal ligament. Acta Odontol Scand. 1981;39:1-13.

53

57. Andreasen J, Paulsen H, Yu Z, Schwartz O. A long-term study of 370 autotransplanted premolars. Part III. Periodontal healing subsequent to transplantation. Eur J Orthodont. 1990;12:25-37.

58. Zeichner-David M, Oishi K, Su Z, Zakartchenko V, Chen L, Arzate H, et al. Role of Hertwig's Epithelial root Sheath Cells in Tooth Root Development. Developmental Dynamics. 2003;228(651):651-63.

59. Slagvolds O, Bjercke B. Autotransplantation of premolars with partly formed roots. A radiographic study of root grwoth. Am J orthod. 1974;66(4):355-66.

60. Kristerson L, Andreasen J. Influence of root development on periodontal and pulpal healing after replantation of incisors in monkeys. Int J Oral Surg. 1984;13(4):313-23.

61. Robertson A, Andreasen F, Bergenholtz G, Andreasen J, Norén J. Incidence of Pulp Necrosis Subsequent to Pulp Canal Obliteration from trauma of Permanent Incisors. J Endod. 1996;22(10):557-60.

62. Laureys W, Cuvelier C, Dermaut L, De Pauw G. The critical apical diameter to obtain regeneration of the pulp tissue after tooth transplantation, replantation or regenerative endodontic treatment. Journal of Endodontics. 2013;39(6):759-63.

63. Watanabe Y, Tamaki M, Takeyama M, Okiji T, Saito C, Saito I. Long-term observation of autotransplanted teeth with complete root formation in orthodontic patients. Am J orthod Dentofacial Orthop. 2010;138:720-6.

64. Kugelberg R, Tegsjö U, Malmgren O. Autotransplantation of 45 teeth to the upper incisor region in adolescents. Swed Dent J. 1994;18(5):165-72.

65. Lundberg T, Isaksson S. A clinical follow-up study of 278 autotransplanted teeth. British Journal of Oral and Maxillofacial Surgery. 1996;34:181-5.

66. Czochrowska E, Stenvik A, Bjercke B, Zacchrisson B. Outcome of tooth transplantation: Survival and success rates 17-41 years posttreatment. Am J orthod Dentofacial Orthop. 2002;121:110-9.

67. kvint S, Lindsten R, Magnusson A, Nilsson P, Bjerklin K. Autotransplantation of Teeth in 215 Patients. Angle Orthod. 2010;80:446-51.

68. Gonnissen H, Politis C, Schepers S, Lambrichts I, Vrielinck L, Sun Y, et al. Long-term success and survival rates of autogenously transplanted canines. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010;110:570-8.

69. Plakwicz P, Wojtowicz A, Czochrowska E. Survival and success rates of autotransplanted premolars: A prospective study of the protocol for developing teeth. Am J orthod Denofacial Orthop. 2013;144:229-37.

70. Isiksal E, Hazar S, Akyalcin S. Smile esthetics: perception and comparison of treated and untreated smiles. Am J orthod Denofacial Orthop. 2006;129:8-16.

71. Morley J, Eubank J. Macroesthetic elements of smile design. JADA. 2001;132:39-45.72. Frese C, Staehle H, Wolff D. The assessment of dentofacial esthetics in restorative

dentistry. JADA. 2012;143(5):461-6.73. Ritter D, Gandini L, Pinto A, Ravelli D, Locks A. Analysis of the smile photograph.

World J Orthod. 2006;7:279-85.74. Gehrke P, Degidi M, Lulay-Saad Z, Dhom G. Reproducibility of the Implant Crown

Aesthetic Index- Rating aesthetics of single-implant crowns and adjacent soft tissue with regard to dental specialization. Clinical Implant Dentistry and Related Research. 2009;11(3):201-13.

75. Kokich V. Esthetics: the Orthodontic- Periodontic Restorative Connection. Semin Orthod. 1996;2:21-30.

54

76. Wolfart S, Thormann H, Freitag S, Kern M. Assessement of dental appearance following changes in incisor proportions. Eur J Oral Sci. 2005;113(2):159-65.

77. Levin E. Dental esthetics and the golden proportion. J Prosthet Dent. 1978;40(3):244-52.

78. Rosenstiel S, Ward D, Rashid R. Dentists' preferences of anterior tooth proportion: a web based study. J Prosthodont. 2000;9(3):123-36.

79. Janson G, Branco N, Fernandes T, Sathler R, Garib D, Lauris J. Influence of orthodontic treatment, midline position, buccal corridor and smile arc on smile attractiveness. A systematic review. Angle Orthod. 2011;81:153-61.

80. Witt M, Flores-mir C. Laypeople's preferences regarding frontal dentofacial esthetics. Tooth-related factors. JADA. 2011;142(6):635-45.

81. Ryge G, Snyder M. Evaluation of the clinical quality of restorations. J Am Dent Assoc. 1973;87:369-77.

82. Engel E, Gomez R, Axmann K. Ästhetikbewertung von implantologischen einzelzahnersatz. Z Zahnärztl Implantol. 2001;17:148-53.

83. Jemt T. Regeneration of gingival papillae after single-implant treatment. Int J Periodontics Restorative Dent. 1997;17:326-33.

84. Jemt T. Restoring the gingival contour by means of provisional resin crowns after single-implant treatment. Int J Periodontics Restorative Dent. 1999;19:20-9.

85. Meijer H, Stellingsma K, Meijndert L, Raghoebar G. A new index for rating aesthetics of implant-supported single crowns and adjancent sof tissues- The Implant Crown Aesthetic Index. Clin Oral Implants Res. 2005;16:645-9.

86. Testori T, Bianchi F, Del Fabbro M. Implant aesthetic score for evaluating the outcome: immediate loading in the aesthetic zone. Pract Proced Aesthet Dent. 2005;17:123-30.

87. Fürhauser R, Benesch T, Haas R, Mailath G, Watzek G. Evaluation of the soft tissue around single-tooth implant crowns: the pink esthetic score. Clin Oral Implants Res. 2005;16:639-44.

88. Belser C, Vailati F, Bornstein M, Weber H, Buser D. Outcome Evaluation of Early Placed Maxillary Anterior Single-Tooth Implants Using Objective Esthetic Criteria: A Cross-Sectional, Retrospective Study in 45 Patients with a 2- to 4-Year Follow-Up Using Pink and White Esthetic scores. J Periodontol. 2009;80:140-51.

89. Czochrowska E, Stenvik A, Zacchrisson B. The esthetic outcome of autotransplanted premolars replacing maxillary incisors. Dent traumatol. 2002;18:237-45.

90. Czochrowska E. Autotransplantation of premolars to replace maxillary incisors: A comparison, with natural incisors. Am J orthod Dentofacial Orthop. 2000;118:592-600.

91. Czochrowska E, Stenvik A, Album B, Zachrisson B. Autotransplantation of premolars to replace maxillary incisors: A comparison with natural incisors. Am J orthod Denofacial Orthop. 2000;118:592-600.

92. De Rouck T, Eghbali A, Collys K, De Bruyn H, Cosyn J. The gingival biotype revisited: transparency of the periodontal probe through the gingival margin as a method to discriminate thin from thick gingiva. J Clin Periodontol. 2009;36:428-33.

93. Loë H. The Gingival Index, The Plaque Index and the Retention Index systems. Journal of Periodontology. 1967;38(6):610-6.

94. Ainamo J, Bay I. Problems and proposals for recording gingivitis and plaque. International dental journal. 1975;24(4):229-35.

55

95. Muhlemann H. Gingival sulcus bleeding-aleading symptom in intial gingivitis. Helv Odontol Acta. 1971;15:107-13.

96. Cosyn J, Eghbali A, De Bruyn H, Dierens M, De Rouck T. Single Implant Treatment in Healing Versus Healed Sites of the Anterior Maxilla: An Aesthetic Evaluation. Clinical Implant Dentistry and Related Research. 2012;14(4):517-26.

97. Fleiss J, Cohen J. The equivalence of weighted kappa and the intraclass correlation coefficient as measures of reliability. Educational and Psychological Measurement. 1973;33(3):613-9.

98. Melsen B, Allais D. Factors of importance for the development of dehiscences during labial movement of mandibular incisors: a retrospective study of adult orthodontic patients. Am J Orthod Dentofacial Orthop. 2005;127(552-561).

99. Olsson M, Lindhe J. Periodontal characteristics in individuals with varying form of the upper central incisors. . J Clin Periodontol. 1991;18:78-82.

100. Patil R, Van Brakel R, Mahesh K, De Putter C, Cune M. An Explatory Study on Assessment of Gingival Biotype and Crown Demensions as Predictors for Implant Esthetics Comparing Caucasian and Indian Subjects. J of Oral Implantology. 2013:308-13.

101. Kan J, Morimoto T, Rungcharassaeng K, Roe P, Smith D. Gingival biotype assessment in the esthetic zone: visula versus direct measurement. Int J Periodontics Restorative Dent. 2010;30(3):237-43.

102. Müller H, Schaller N, Eger T. Ultrasonic determination of thickness of masticatory mucosa. A methodological study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1999;88:248-53.

103. Eghbali A, De Bruyn H, Cosyn J, Kerkaert I, Van hoof T. Ultrasonic assessment of mucosal thickness around implants: validity, reproducibility and stability of connective tissue grafts at the buccal aspect. Clin Implant Dent Relat Res. 2014;Epub a head of print.

56

                  IX.    Appendix

APPENDIX  I

57

APPENDIX  II

      Questionnaire                        

About  the  treatment

1.  Do  you  remember  the  surgical  operation?

Very  well   not  at  all  

 

2.  What  was  your  experience  of  pain/discomfort  in  relation  to  the  operation?

Very  little  pain   very  painful  

3.  Was  the  decision  to  do  the  transplantation  to  solve  your  dental  problem  easy  or  difDicult  for  you/your  parents?

easy   dif3icult  

   

About  the  result

4.  Do  you  know  today  which  teeth  was  transplanted?

Know  for  sure   do  not  know  

     

58

5.  Do  you  know  the  original  position  in  the  mounth  of  the  transplanted  tooth?

Know  for  sure   do  not  know  

       

6.  How  do  you  perceive  the  aesthetic  outcome  the  transplanted  tooth  compared  with  the  rest  of  your  teeth?

         the  same  as  others   quite  different

   

7.  What  is  your  opinion  about  the  position  of  the  transplanted  tooth  in  the  dental  arch?

Fits  nicely  in   totally  wrong  position  

     

8.  What  effort  does  it  take  to  maintain  the  transplanted  tooth  compared  with  the  other  teeth?

The  same  as  others   takes  extra  effort  

   

9.  How  satisDied  are  you  with  the  aesthetic  outcome  of  the  gums  surrounding  the  crown?

Excellent  aesthetics   very  poor  aesthetics  

10.  How  satisDied  are  you  with  the  aesthetic  outcome  of  the  crown?

Excellent  aesthetics   very  poor  aesthetics  

       

59

APPENDIX  III        

Informed  consent  form  for  patients  and  parents  of  patientsEsthetiek van autotransplantatie van een premolaar als vervanging van een bovenincisief, een retrospectieve studie

Hierbij bevestig ik, ondergetekende (naam & voornaam) ____________________________________dat ik over de studie ben ingelicht en een kopie van de “Patiënteninformatie” en het “Toestemmingsformulier” ontvangen heb. Ik heb de informatie gelezen en begrepen. Mijn tandarts heeft mij voldoende informatie gegeven met betrekking tot de voorwaarden en de duur van de studie. Bovendien werd mij voldoende tijd gegeven om de informatie te overwegen en om vragen te stellen, waarop ik bevredigende antwoorden gekregen heb.

–Ik heb begrepen dat ik mijn deelname aan deze studie op elk ogenblik mag stopzetten nadat ik mijn arts hierover heb ingelicht, zonder dat dit mij enig nadeel kan berokkenen.Ik geef toestemming aan de verantwoordelijken van de opdrachtgever (naam invullen) en aan regulerende overheden om inzage te hebben in mijn patiëntendossier. Mijn medische gegevens zullen strikt vertrouwelijk behandeld worden. Ik ben mij bewust van het doel waarvoor deze gegevens verzameld, verwerkt en gebruikt worden in het kader van deze studie.Ik ga akkoord met de verzameling, de verwerking en het gebruik van deze medische gegevens, zoals beschreven in het informatieblad voor de patiënt. Ik ga eveneens akkoord met de overdracht en de verwerking van deze gegevens in andere landen dan België.Ik ga akkoord met het gebruik door de opdrachtgever van deze gecodeerde medische gegevens voor andere onderzoeksdoeleinden.Ik stem geheel vrijwillig toe om deel te nemen aan deze studie en om mee te werken aan alle gevraagde onderzoeken. Ik ben bereid informatie te verstrekken i.v.m. mijn medische geschiedenis, mijn geneesmiddelengebruik en eventuele deelname aan andere studies.Ik ga ermee akkoord dat mijn huisarts/specialist en andere zorgverleners die bij mijn behandeling betrokken zijn, op de hoogte worden gebracht van mijn deelname aan dit onderzoek.

Datum: ____________________

Handtekening patiënt(e) (of wettelijk vertegenwoordig(st)er):_____________________________

Deel enkel bestemd voor het onderzoeksteam Ik, ondergetekende, __________________, bevestig hierbij dat ik, ________________________ (naam van de patiën(e) voluit) of zijn wettelijke gegevens vertegenwoordig(st)er) heb ingelicht en dat hij (zij) zijn (haar) toestemming heeft gegeven om deel te nemen aan de studie.

Datum: ____________

Handtekening: __________________

                             

60

APPENDIX  IV.

Patients  information  form

Esthetiek van autotransplantatie van een premolaar als vervanging van een bovenincisief, een retrospectieve studie

Beste Mevrouw/ MeneerBeste Juffrouw/ Jongeheer

Tegenwoordig worden er regelmatig tanden getransplanteerd van 1 plaats in de mond naar een andere plaats in de mond. Deze transplantaties hebben een hoog slaagpercentage.Wij vragen ons af of het esthetisch resultaat van deze transplantaties na enkele jaren nog steeds bevredigend is.

Wat is het doel van het onderzoek?We willen te weten komen of het esthetisch resultaat van een tandtransplantatie nog steeds bevredigend is na enkele jaren?

Hoe gaan we dit onderzoeken?Patienten die vroeger een tandtransplantatie hebben gehad van een kleine kies naar het bovenfront worden opnieuw gecontacteerd. Er wordt een klinische foto genomen van de getransplanteerde tand. Op deze foto zal de onderzoeker verschillende aspecten van het tandvlees en de kroon scoren. Vervolgens wordt er ook aan de patient gevraagd een vragenlijst in te vullen, waaruit we de tevredenheid van de patient over het esthetisch resultaat van de transplantatie kunnen peilen.

Als u akkoord gaat om aan deze studie deel te nemen, zullen uw persoonlijke en klinische gegevens tijdens deze studie worden geanonimiseerd (hierbij is er totaal geen terugkoppeling meer mogelijk naar uw persoonlijke dossier) In overeenstemming met de Belgische wet van 8 december 1992 en de Belgische wet van 22 augustus 2002, zal uw persoonlijke levenssfeer worden gerespecteerd. Als de resultaten van de studie worden gepubliceerd, zal uw anonimiteit aldus verzekerd zijn. De experimentenwet van 7/05/2004 verplicht ons om deelnemers aan wetenschappelijke projecten te verzekeren voor de deelname en het risico (hoe klein ook) dat men loopt. De waarschijnlijkheid dat u door deelname aan deze studie enige schade ondervindt, is extreem laag. Indien dit toch zou voorkomen, wat echter zeer zeldzaam is, werd er een verzekering afgesloten conform de Belgische wet van 7 mei 2004, die deze mogelijkheid dekt.

61

APPENDIX  V.

62

63