angle and chin position can improve the facial esthetics(Reitzik, 1980).

usually have labially inclined maxillary incisors due to dental compensation. In these cases, it is possible to get more esthetic results with posterior impaction of maxilla because it impro ves inclination of upper incisor and increases the amount of setback Pogoion and Menton by allowing the mandible to rotate backward. In addition, alternations of Mandibular plane angle and chin position can improve the facial esthetics(Reitzik, 1980). For these reasons, recent reports indicate that bimaxillary surgeries have become more frequent.
Post-operative relapse of orthognathic surgery can reduce facial esthetics. Some occlusal changes result from relapse can cause functional problems. When the relapse occurs, it could be solved through prolongation of inter-maxillary fixation or post-operative orthodontic treatment. But second surgery would be needed if there are severe skeletal problems. The post-operative relapse can be the measure of success or failure in orthognathic surgery. There are a number of factors associated with post-operative relapse such as surgical method, period and method of inter-maxillary fixation, amount of surgical movement, and tension of soft tissue.(Franco, et al., 1989). Alternation of occlusal plane due to posterior impaction of maxilla also affects the stability of treatment result.
The purpose of this study was to evaluate the effects of posterior impaction of maxilla to post-operative stability in skeletal class III patents. The null hypothesis was that posterior impaction of maxilla
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골격성 제3급 부정교합 환자에서 상악골 posterior impaction에 따른 술후 경조직 안정성에 관한 연구 / 백민정