Objective:To correct mandibular prognathism with the technique of sagittal split ramusosteotomy(SSRO) and extraoral vertical ramus osteotomy(EVRO).
目的：应用粗裂钻和薄刃锐利骨凿施下颌骨升支垂直截骨术和矢状劈开截骨术治疗下颌骨前突畸形。
2
Objective To establish the three-finite element models of the mandible before and after Sagittal split ramusosteotomy(SSRO).
目的建立下颌支矢状劈开后退术前后的下颌骨三维有限元模型。
3
Objective: To study the distribution of stress caused by different mastication muscles in mandibular ramus operative area after sagittal split ramus osteotomy (SSRO), so as to guide the clinical work.