Prevalence of Dentinogenesis Imperfecta in a French Population.

BACKGROUND: Dentinogenesis imperfecta is a genetic disorder of the dentin occurring during the tooth development. It leads to many structural changes that can be identified clinically (brownish colored teeth, cracked enamel) and radiologically (globular crown, cervical constriction, short roots, and obliterated pulp chamber and/or root canals). The aim of this study was to determine by panoramic radiographs assessment the incidence of dentinogenesis imperfecta in a group of patients attending a specialized maxillofacial imaging center in Paris, France. MATERIAL AND METHODS: A retrospective observational study was conducted using panoramic radiographs of 8830 patients (3723 males and 5107 females), which were used to search the radiological criteria of dentinogenesis imperfecta. RESULTS: In our sample, the prevalence of dentinogenesis imperfecta was 0.057%. Out of the 8830 subjects, 0.080% of the males presented the radiological signs of the dentinogenesis imperfecta against 0.039% of the females. CONCLUSION: In our study, we found that dentinogenesis imperfecta is a relatively rare dental anomaly in France, with a rate different from the rates reported in other studies and with no disparity in prevalence among genders.

Efficacy of bone substitute material in preserving volume when placing a maxillary immediate complete denture: study protocol for the PANORAMIX randomized controlled trial.

BACKGROUND: Bone preservation is an essential issue in the context of last teeth extraction and complete edentulism. The intended treatment, whether a complete denture or an implant placement, is facilitated with a voluminous residual ridge. Bone resorption after multiple extractions has not been as well studied as the bone resorption that occurs after the extraction of a single tooth. Recent advances in bone substitute materials have revived this issue. The purpose of this study is to evaluate the interest in using bone substitute material to fill the socket after last teeth extraction in a maxillary immediate complete denture procedure compared with the conventional protocol without socket filling. METHODS/DESIGN: A randomized, controlled, clinical trial was designed. The 34 participants eligible for maxillary immediate complete denture were divided into two groups. Complete dentures were prepared despite persistence of the last anterior teeth. The control group received a conventional treatment including denture placement immediately after extractions. In the experimental group, in addition to the immediate denture placement, a xenograft bone-substitute material (Bio-Oss Collagen®) was placed in the fresh sockets. The primary outcome of the study is to compare mean bone ridge height loss 1 year after maxillary immediate complete denture placement, with or without bone-substitute material, in incisor and canine sockets. The secondary outcomes are to compare the average bone ridge height and width loss for each extraction site. An original quantitative evaluation method using cone beam computed tomography was designed for reproducible measurements, with a radio-opaque denture duplicate. Two independent operators perform the radiologic measurements. DISCUSSION: The immediate complete denture technique limits bone resorption in multiple extraction situations and thus allows better denture retention and better options for implant placement. To compare the benefit of using any bone socket-filling material, we proposed a quantitative evaluation protocol of resorption in the specific case of the last anterior maxillary teeth extraction with immediate denture placement. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02120053 . Registered on 18 April 2014.

[Imagery and orthodontics: trends, present and future]. / Imagerie et orthopédie dento-faciale: évolution, présent et avenir.

From the first dental image in 1895 and the first image of the head in 1896 by Otto Walkhoff to 3D modern cephalic assessment there has been a continuous evolution in imaging techniques. Digital cephalic volume data processing allows 2D and 3D reformations in accordance with morphologic, topographic and biodimensional anatomic needs. In France, Jacques Treil demonstrated its application in cephalometry through his CT scan research. The transcription of European Directives to national laws leads to rigorous radioprotection measures. The worldwide spread of cone beam technique devoted specifically to dentomaxillofacial imaging should now reduce the reluctance of orthodontists to provide radiological examinations to children by significantly reducing radiation exposure. This is certainly the technique of the future.