BSSRO 后退下颌骨术后的下颌角形态对比研究.

Objective To analyze the changes of morphology of mandibular angle after bilateral sagittal split ramus osteotomy (BSSRO). To study the effect of BSSRO on facial contour of patients. Methods The clinical data of 35 patients with skeletal class Ⅲ malocclusion from June 2018 to June 2020 were retrospectively analyzed. Three-dimensional CT was taken at 1 week before operation (T1) and 8 to 12 months after operation (T2). The Adobe Photoshop CS6 and MaterialiseProPlan CMF 3.0 were used for image processing and measurement. Results Compared with mandibular width before operation, the mandibular width increased 2.47 mm after BSSRO. The paired t-test showed that the difference before and after operation was statistical significant (P<0.01). The mandibular angle decreased, the mandibular plane angle and the angle between mandibular branch plane and Frankfurt horizontal plane (F-H plane) increased. Conclusion For patients with skeletal Class Ⅲ malocclusion, the width of mandibular angle after BSSRO tends to increase. [ABSTRACT FROM AUTHOR]