[Orthodontics, orthognatic surgery and their functional environment].

Dento-dental and dento-maxillary dysharmonies and maxillo-mandibular dysmorphologies are impairments that can be treated either by orthodontics and surgery, or with a combination of orthodontics and orthognatic surgery. Respiration, deglutition, phonation and succion play a predominant role in the occurrence of maxillofacial dysmorphologies. Contributing factors to such impairments include upper airway function disorders such as respiration, deglutition, phonation, sucking. Abnormal functions must be extensively studied in management of maxillofacial patients in order to achieve stable results and to avoid relapses.