Orthodontia-Implantology- Prosthodontics in Rare Diseases: the Oligodontia Example

DOI: 10.1051/odfen/2013506 J Dentofacial Anom Orthod 2014;17:204 RODF / EDP Sciences

Orthodontia-implantology- prosthodontics in rare diseases: the oligodontia example

Khanh NHAM, Steve TOUPENAY, Dac Alexandre VUONG, Nadeem SAMEE, Benjamin FOURNIER, Ste´ phane KERNER

ABSTRACT Among rare diseases, a fifth of them are associated with oral manifestations. The most frequent are: enamel dysplasia, cleft lip or palate and oligodontia. Beside the pathology, patients are eager of functional therapeutics which often needs prosthodontics. This oral rehabilitation aims to a better life quality. Teeth absence management in the case of oligodontia necessitates critical analysis of the supporting tissues: the periodontium and the underlying bone. Deciduous teeth with resorbed roots and hypoplasic permanent teeth are often observed. Thus, some questions arise: can we use them as abutments or can we restore them knowing that they present an anomaly in their position and are more fragile? How do we replace many teeth when bone is lacking (clefts, agenesis)? Can we implant on a missing tooth site or can we use autograft? What do we expect for periodontal healing? Adjacent teeth have often migrated, occlusion is unstable due to mixed dentition and patient’s disease. For example, in mandibular incisors agenesis cases, the remaining deciduous teeth are used when consultation happens at adolescence. This results in upper jaw incisors migration toward mandible and thus an anterior overbite. Orthodontic treatments will allow to recreate gap width and a normal occlusion in order to perform prosthodontics treatment in the best possible conditions. Giving the weak dental and periodontal supports, our attention will be focused on choosing the best option between tooth and implant supported prosthodontics. During the mixed dentition, orthodontic treatment and aesthetic rehabilitation have to be planed at the same time and to last until ‘‘definitive’’ implant and periodontal therapies are possible. In this article, we will present one oligodontia case report to illustrate a possible solution.

KEY WORDS

Orthodontics implantology prosthesis oligodontia

Article received: 17-09-2013. Address for correspondence: Accepted for publication: 22-11-2013. Khanh NHAM 3, alle´e Louis Jouvet, 77200 Torcy 1 [email protected]

Article available at http://www.jdao-journal.org or http://dx.doi.org/10.1051/odfen/2013506 K. NHAM, S. TOUPENAY, D. A. VUONG, N. SAMEE, B. FOURNIER, S. KERNER

INTRODUCTION AND DESCRIPTION OF THE REFERENCE CENTER

Since its designation in 2007 as a restoration. But the specificity of Reference Center of Rare Disease for these pathologies comes from the the Face and Oral Cavity (MAFACE), need to time the treatment to the Rothschild Hospital has treated 631 pa- stages of growth, child, adolescent tients including 57% with congenitally and then young adult using the ap- missing teeth23. The annual number of propriate technical as well as psy- new patients is approximately 100, chological approach. Accommodating about half of them present with an ab- patients transitioning into adulthood normality in the number of teeth (inter- in the best way possible during nal data from the MAFACE reference prosthetic restoration and implant center 2012). The management of treatment will help them to accept thesepatientsattheMAFACErefer- the treatment and help the practi- ence center is complex and requires tioner to have the best conditions to multidisciplinary treatment. perform it so that it lasts throughout This article addresses the close the lifetime. cooperation that exists between Coordination within the MAFACE orthodontics and implant-prosthetics reference center requires the inter- and focuses on the therapeutic man- vention of specialists in dento-facial agement of patients presenting with orthopedics, general dentistry and agenesis of multiple teeth, particu- maxillofacial surgeons who adapt larly, oligodontia. This disorder is treatment to the clinical picture and characterized by agenesis of 6 or psychological make-up of these pa- more permanent teeth, excluding tients. Conventional advances in spe- wisdom teeth14. According to differ- cific therapeutic management of ent studies, the prevalence of agen- agenesis of multiple teeth have esis of permanent teeth can vary made it possible to establish a speci- from .09% to .14%2,18. Several rare fic protocol for treatment for children disorders, whether syndromic or not, since 2007, and for adults since include agenesis of multiple teeth in 2012. Therefore, the nomenclature their clinical picture, with ectodermal confers legal recognition to patients dysplasia as the most commonly with oligodontia who then qualify for mentioned11. The early diagnosis and reimbursement of costs for implant therapeutic management of these treatment after the genetic defect rare disorders requires prosthetic and has been confirmed by an expert at orthodontic follow-up care in order to the center for expertise, as re- ensure an ideal clinical situation so quested by the division of rare dis- that when the patient becomes an eases of the National Health adult, it will then be possible to pro- Insurance Fund. The available scienti- vide a reliable restorative treatment. fic literature is limited to the opinions The common objective of any of experts or to case series. This re- treatment is functional and esthetic presents limited scientific proof17.

2 K. Nham, S. Toupenay, D. A. Vuong, N. Samee, B. Fournier, S. Kerner. Orthodontia-implantology- prosthodontics in rare diseases: the oligodontia example ORTHODONTIA-IMPLANTOLOGY-PROSTHODONTICS IN RARE DISEASES: THE OLIGODONTIA EXAMPLE

CHARACTERISTICS OF OLIGODONTIA

Dentoalveolar characteristics relatives of these patients. This abnormality of shape might be A review of the literature shows more marked in the case of some common dento-skeletal charac- oligodontia that shows a notice- teristics in these patients. able difference in tooth dimen- • The developmental defect of the sion for the maxillary lateral dental organ may be linked to a incisors and the mandibular ca- lack of maturation or lack of tooth nines10,24. buds (defect in genetic coding or • In the labial-lingual direction, the embryopathology). dimensions of the alveolar pro- • The most frequently involved cess are reduced in the area of teeth are those at the end of a agenesis, whether or not primary tooth series9. teeth are present. The presence • When they are present, decid- of crowns and dental roots is uous teeth erupt unpredictably. important for the stimulation of They may either persist in a the development and the quality stable manner in the arch with of the alveolar process, since no radicular breakdown or on the their absence can complicate contrary fall out or root resorption implant treatment procedures. may even begin and eventually This is even more flagrant when there will be ankylosed teeth there is an early loss of decid- in the arch12, and this takes uous teeth that leads to a bone place, despite the absence of defect. succedaneous tooth buds. Pri- mary molars may then become Dentofacial characteristics of submerged, and consequently, oligodontia tooth elongation of the opposing dentition occurs16. • On the sagittal plane, several • Structural abnormalities may be studies1,25 suggest that a re- detected such as dysplasia that truded chin and a very open can vary in severity. interincisal angle are present. • The co-existence in the arch of This explains the lingual inclina- such hypotrophic primary and tion of the mandibular incisors permanent teeth is possible, that is often combined with creating interdental gaps that palatal inclination of maxillary are difficult to manage. We can incisors. The profile is therefore observe variations in the mesio- very straight or even concave distal dimensions even though with prognathia. they may not appear significant • The absence of teeth, especially as well as a morphological left- in the lateral sectors, often right asymmetry of teeth in pa- includes a decrease in the height tients with oligodontia20. These of lower third of the face variations may be found in the with significantly more prominent

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nasal and chin furrows as well as – lingual inclination of the incisor in an incisal overjet. It is not unusual both arches with loss of 6 teeth to see even more prominent on average including the maxil- wear facets appear on the inci- lary premolars; sors if primary teeth affected by – absence of 7 teeth or more agenesis are involved. including the molars with re- The research of Marijn Cre´ ton truded chin. et al.8,9 on cases of dental agenesis • A reduction in the length of the indicates that, although bone trabecu- maxillary and mandibular arches lation shows no variations in either respectively of 4.40 mm and healthy or oligodontia patients, there 2.80 mm may also be observed are three interesting discrimatory ce- in patients presenting oligodon- phalometric variables: the sagittal re- tia. The intercanine distance is lationships of the maxilla (SNA, SNB), decreased by 2.82 mm in the the intercisal angle and the height of maxilla and by 2.70 mm in the the lower third of the face (possibly mandible, and the intermolar dis- the relationships of the heights of tance is also decreased by each third as described by the 3.40 mm in the maxilla and Wendell-Willie Equation). Patients 1.80 mm in the mandible6. can be grouped into different cate- These clinical characteristics make gories: orofacial restorations complicated – loss of few teeth with little and compromises are often neces- impact on the face; sary. – loss of 4.3 teeth on average with labial inclination of the mandibular incisors;

ORTHODONTIC TREATMENT

Orthodontic treatment manage- will take place in concert with a ment in cases of oligodontia may be periodontal-prosthetic restoration with comprised of two phases: the man- a choice between a bridge or an im- agement of edentulous spaces and a plant, closure or reopening of the more comprehensive dentofacial re- spaces as in this case, may cause a di- storation. vergence of the roots in the collateral In the first case, the number of teeth. The occlusal scheme may show missing teeth is relatively reduced a discrepancy in the normal sagittal re- and involves the end of series teeth lationships of the teeth if there are a (classically second premolars and limited number of teeth that will be re- maxillary lateral incisors). The reper- placed (for example: Class II therapy cussions on the support tissue are with agenesis of the lateral incisors). not as great. The management of the Of course, the practitioner must take space beyond a possible arch length into consideration potential abnormal- discrepancy due to excess space ities of shape or structure when

4 K. Nham, S. Toupenay, D. A. Vuong, N. Samee, B. Fournier, S. Kerner. Orthodontia-implantology- prosthodontics in rare diseases: the oligodontia example ORTHODONTIA-IMPLANTOLOGY-PROSTHODONTICS IN RARE DISEASES: THE OLIGODONTIA EXAMPLE

deciding on treatment. The principal It is often necessary to perform difficulty of orthodontic treatment for coronal reconstruction beforehand, patients with oligodontia will be the with either pediatric crowns for the anchorage system and the quality of molars or micro-filled composite ve- the supporting bone. The permanent neers for the anterior zone. The re- and primary teeth present in the construction contributes substantially mouth are often distant from one to the reliability of the placement of another that subsequently creates dia- orthodontic brackets and to their dur- stemas. In addition, they may present ability throughout treatment that al- with reduced coronal volume. It is of- lows for better control. ten necessary to divide the mouth into In cases of more extensive miss- different zones for procedures in order ing teeth, the facial repercussions on to create more solid supports and an- the support tissues often initially re- chorage devices such as miniscrews quire the fabrication of occlusal are an indispensable tool. However, in splints in order to confirm the rehabi- the previously edentulous areas, the litation of the height of the lower weakness of the bone support, both third of the face and as well as the in the buccal-lingual direction as well restoration of the support for the de- as in the coronal-apical direction, re- sired labial and cheek-side structures. quires that the orthodontist takes The participation of the patient in the every precaution during dental move- process of indicating satisfaction with ments by using gentle and continuous the sequential outcomes is essential force to avoid the risk of exposing the to the acceptance of achieved re- roots. This is especially true when sults. A profile cephalometric Xray congenitally missing teeth occur as will help to confirm the correct incli- part of a syndrome such as cleft of lip nation of the condylar heads and will and palate with regard to the closure be reconfirmed by a new height that of surgical margins. Sometimes, the is symptom free. decision is made to preserve the pri- Of course, this is just an example mary teeth, either to prevent loss of of treatment management for iso- the support until the patient is old en- lated oligodontia, the treatment plan ough to insert the implants or to mask becomes more complicated in cases them with composite or resin ve- of associated sagittal imbalance and neers. In this case, during orthodontic the practitioner and patient may opt movement every precaution should for a traditional orthognathic surgery be taken given that root resorption treatment plan. may occur.

IMPLANT PROSTHETIC TREATMENT

As in any complicated situation along with a CT-scan in order to vi- and based on the principle that im- sualize bone volume and to plan for a plants guide surgery, making a diag- bone graft if needed. The bone graft nostic wax up on study models and a may be accomplished with onlay radiographic guide are indispensable autogenous grafting or with a bone

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substitute material. They may come In the vertical direction, the lack of from mandibular, coxal or parietal dental development can lead to a sig- bones. nificant deficiency of the height of In the buccal-lingual and mesial- the alveolar bone and therefore it be- distal direction, choosing narrow- comes impossible to have the stan- diameter implants is an alternative7. dard 8 to 10 mm total length used This requires that the dental abut- for an implant, with a higher risk of ment be customized in relation to the damaging structures such as the low- desired emergence profile of the er alveolar vascular nerve plexus or teeth. If an insufficient alveolar ridge the maxillary sinus membrane. In this in the mesial-distal plane can be case, inserting short implants (less managed by orthodontic opening of than 8 mm) may be an alternative to the space, the buccal-lingual plane vertical bone grafting and the place- 19 need only be treated surgically by in- ment of standard sized implants . creasing the bone volume.

IMPACT OF GROWTH ON REHABILITATION

The prosthetic treatment repre- then three different age categories for sents the final phase of oral rehabili- prosthetic rehabilitation: adolescents, tation. There is a whole therapeutic young adults and adults. Although arsenal available for restoring the treatment plans are individualized, it is function and esthetics of the patient best to treat patients as soon as possi- centered around either fixed prosthe- ble. tic restorative solutions or with remo- Treatment for adolescents consists vable solutions with or without the in preparing the dental arch for a use of retention devices. prosthetic rehabilitation at the end of With regard to prosthetics, the the growth period. The treating prac- practitioner will have to take into ac- titioner, in collaboration with the count two fundamental criteria: the orthodontist, plans for the replace- age of the patient as well as his den- ment of missing teeth. Based on the tal and skeletal structure, as deter- prosthetic procedure, the dentist de- mined by the intrinsic and extrinsic cides to maintain, to close or to open value of each tooth. the space. In cases of a single miss- These patients, once they learn ing tooth in one quadrant in adoles- about the existence of new legal provi- cents, an adhesive technique with a sions concerning treatment for agen- bonded prosthesis is preferable. On esis of multiple teeth, come in at any the one hand, this make it possible age for consultation. Since real age is to avoid removable appliances and not the main criterion to consider but their disadvantages, and on the other rather the dental and skeletal matura- to maintain the interdental space, tion according to Thilander22, there are whether or not it was created by

6 K. Nham, S. Toupenay, D. A. Vuong, N. Samee, B. Fournier, S. Kerner. Orthodontia-implantology- prosthodontics in rare diseases: the oligodontia example ORTHODONTIA-IMPLANTOLOGY-PROSTHODONTICS IN RARE DISEASES: THE OLIGODONTIA EXAMPLE

the orthodontist, for implant treat- on the eruption of the permanent ment when growth has definitively teeth and on the mobility of the adja- stopped. cent teeth during orthodontic treat- In severe cases of oligodontia, or ment. The other short-term solutions anodontia, inserting implants before may be fixed using temporary de- the end of skeletal development is vices attached to adjacent teeth by not recommended, except in the bonded wires, or temporary teeth in- symphyseal region. It is only advisa- tegrated in the orthodontic arc. The ble to place from two to four sym- case of Mrs. M. (Figs. 1 to 11) illus- physeal implants in children ages 6 trates perfectly how orthodontics, im- to 18 in cases where the practitioner plantology and prosthetics had to be is planning a rehabilitation with an im- coordinated in this case of agenesis plant-supported removable complete where the decision was made to dentures, if wearing a single implant conserve the maximum number of overdenture has proved unsuccess- primary teeth in the mandible and to ful11,13. reopen the spaces of the lateral incisors and canines in preparation for an The comprehensive strategy for implant-supported replacement. treating a young adult with oligodontia, is to suggest replacement Implant-prosthesis rehabilitation for therapy, while at the same time young adults is possible at the end respecting the craniofacial develop- of puberty, but according to a study 4 ment of the patient. Bio-adaptable carried out by Bernard , the coronal partial implants, guidance for the reconstruction is at risk of developing eruption of permanent teeth, and an infraclusion in the long term. Ther- closing or opening spaces between apy initiated too early can also have the permanent teeth for a per- an impact on the development of the manent fixed solution at the end of arches, and on the eruption and posi- 15 the growth period, prevents any tion of adjacent toothbuds . The risk iatrogenic damage to the residual of periodontal recession on the cervi- teeth. If spacing has to be main- cal edge of an anterior prosthesis in tained, it will generally be done a young adult forces us to position by removable and bio-adaptable pros- the implants more distally and to opt theses that should be monitored and for masking the natural teeth with es- reassessed at regular intervals, based thetic cosmetics and a coronoplasty

Figure 1 Figure 2 Clinical view during the course of DFO treatment Occlusal view. (DFO treatment performed by Dr. Reveret).

Rev Orthop Dento Faciale 2014;17:204 7 K. NHAM, S. TOUPENAY, D. A. VUONG, N. SAMEE, B. FOURNIER, S. KERNER

Figure 3 Panoramic xray at the end of orthodontic treatment.

Figure 4 Figure 5 Insertion of implants in tooth positions 22 23. Insertion of implants in tooth positions 12 13.

Figure 6 Sutured flaps with positioning of Figure 7 Figure 8 buried connective tissue grafts in a Sutured flaps with positioning of Placement of impression copings frontal view. buried connective tissue grafts in a and protecting the brackets with palatal view. wax.

8 K. Nham, S. Toupenay, D. A. Vuong, N. Samee, B. Fournier, S. Kerner. Orthodontia-implantology- prosthodontics in rare diseases: the oligodontia example ORTHODONTIA-IMPLANTOLOGY-PROSTHODONTICS IN RARE DISEASES: THE OLIGODONTIA EXAMPLE

Figure 9 Figure 10 Prosthesis used in a frontal view. Prosthesis used in a palatal view.

Figure 11 Panoramic xray of the teeth at the end of comprehensive treatment.

to ensure better matching with the In cases where an orthodontic replaced tooth. treatment is planned, treatment man- In the adult patient, depending on agement is more comprehensive and the diagnosis, his complaints and his long. The majority of patients with motivation, the potential solutions oligodontia present with a combina- may involve an orthodontic procedure tion of primary and permanent teeth prior to the oral rehabilitation. If there in the arches, and the question of is no preprosthetic orthodontic treat- conserving the primary teeth in pre- ment, the practitioner must strive to paration for a prosthetic rehabilitation be as uninvasive as possible and to must be considered. The extraction adapt treatment to the existing occlu- of primary teeth is not systematically sion, by looking for the best esthetic performed. If the primary second mo- and functional compromise for the lars are present at 20 years of age, patient. In addition to the conven- their prognosis for survival in the long 5 tional therapeutic arsenal, patients term is improved . Studies show with oligodontia can take advantage then the possibility of maintaining the of special financing for implant ther- primary molars in adults, especially apy as well as a screw retained over- primary second molars that subse- denture prosthesis that is a less quently makes it possible to delay 21 expensive rehabilitation for a patient implant therapy . If, in spite of with oligodontia. everything, they must be extracted

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and implant-supported solution is for young adults, an orthodontic treat- elected, the orthodontic and prosthe- ment, as decribed above, will pro- tic plan will be a preparation for the mote the integration of the implant insertion3. Since adult pros- suggested prosthetic elements. thetic solutions are identical to those

CONCLUSION

The various forms of oligodontia in- and functional needs, can easily an- cluded in the category of agenesis of ticipate the various phases and ac- multiple teeth consist of several clini- cept the need to cooperate as well cal manifestations. Depending on the as the outcome of treatment. Re- number of missing teeth, their distri- viewing the oral rehabilitation plan on bution in the arches, the occlusal pic- mock-ups may be a means of win- ture may be disrupted to varying ning the support and cooperation of degrees (extrusion, linguoversion) the patient, and in the same way and the affected support tissue (re- may help the medical team clearly ceded chin, reduction of the peri- understand the desired results. The meter of the arch, collapsed labial need for cooperation between dento- and cheek tissues). facial orthopedics and prosthodontics Clinical therapeutic management is of the utmost importance to en- must necessarily be comprehensive sure the reliability of the rehabilita- and planned in several phases over tion, performed according to the time based on the age of the patient. latest scientific data available, in or- The management must also have a der to therefore avoid the inherent psychological component so that the medical-legal implications of ‘‘lost op- patient, who has so many esthetic portunity’’ for these young patients.

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