Rapid maxillary expansion assisted by palatal mini-implants in adolescents - preliminary study.

Our preliminary clinical study compares the transverse skeletal and dento-alveolar modifications occurring after rapid maxillary expansion with purely dental anchorage or with dental anchorage assisted by palatal mini-implants, in endognathic adolescents aged 12 to 17. Nine patients were treated by means of tooth- and implant-supported expansion, and 7 others by means of a purely tooth-borne expander. The changes, 4 months after expansion, were measured on impressions and front-view X-rays in the 2 groups, and on three-dimensional X-rays for 6 patients treated by tooth- and implant-supported expansion. In our sample, tooth- and implant-supported expansion preserved the alveolar bone of 14/24 and gave rise to less buccal tipping of 16/26 than purely tooth-borne expansion.

[Occlusal aspects of asymmetry]. / Approche occlusodontique des asymétries.

The dysfunctions of the masticatory apparatus can exhibit many different aspects, and multiple etiologies. If, among those, the occlusal causes are minimized today by a majority of the authors, it is nevertheless recognized that asymmetries represent a risk factor for the appearance and the development of dysfunctional pathologies for the masticatory apparatus. In presence of such dysmorphoses, it is of primary importance to proceed to dysfunction screening, which may be followed by a specialized clinical examination of the masticatory apparatus completed when required, by supplementary investigations. This stage enables both to pose the indispensable diagnosis, to evaluate the capacities for adaptation and suggest a coherent therapeutic approach, always starting with reversible treatments prolonged after re-evaluation and validation of their justification, by the stabilization of the occlusal relationships, a phase in which orthodontics often intervene.

[Orthodontic approach to asymmetry]. / Approche orthodontique des asymétries.

From an orthodontic point of view, asymmetries can be gathered in three great clinical entities: mandibular lateral deviations, dental asymmetries without skeletal involvement, skeletal asymmetries. Once the therapeutic aims and the principles of the orthodontic approach of these dysmorphoses have been recalled, the authors present the various orthodontic means implemented in this type of treatment. Four cases treated illustrate those types of treatment. Vertical non-surgical asymmetry may have an obvious local origin, for instance, a unilateral damage to a nerve. but usually, there is no evident origin. Frequently the occlusal slippage of a severe sagittal or a vertical malformation, which may evolve as a borderline surgery case, is suspected to be the real cause. In these cases, the diagnosis is always late, with the ending growth. The treatment needs peculiar strong asymmetric mechanics and, sometimes, unilateral mixed extractions. The post-treatment occlusion can be unstable; for this reason, the finishing steps must be carefully conducted. Four clinical case reports develop these points ov view. Multidisciplinary treatments prove very useful to solve three types of clinical situations. In the adult patient, facial esthetics are indicated in severe dentofacial asymmetries. Esthetic improvements of dental nature are still required in deviated smiles, or frontal tippings of the occlusal plane. In addition, asymmetrical intermaxillary relationships will lead to functional anomalies: TMJ disorders, dental wear or lingual dysfunctions. Finally, multidisciplinary treatments in the adult concern the occlusal transverse anomalies, the lateral crossbites, the Class II subdivisions, the deviations of the inter-incisor midlines or unilateral edentulousness. The various plans of treatment, as well as the orthodontic mechanics used, are illustrated in the following development by clinical cases.