Clinical study on the efficacy of BSSRO combined with mandibular angle contouring surgery in the correction of facial asymmetry

WANG Lei; LIN Yangyang; WANG Mingzhe; YE Weilong; HOU Min

doi:10.3969/j.issn.1673-7040.2025.12.002

Abstract：Objective To evaluate the clinical efficacy of bilateral sagittal split ramus osteotomy(BSSRO)combined with mandibular angle contouring surgery performed simultaneously during bimaxillary orthognathic surgery for the correction of facial asymme-try.Methods A retrospective analysis was conducted on 15 patients with facial asymmetry treated between December 2023 and August 2024.All patients underwent bimaxillary orthognathic surgery,and the mandibular procedure invariably combined BSSRO with mandibular angle contouring surgery.For height asymmetry,mandibular angle osteotomy is recommended.Post-operative follow-up lasted 1 year.Pre-operative and 3-month postoperative CT data were collected,and three-dimensional reconstruction was performed using the digital soft-ware ProPlan 3.0(Materialise Medical,Belgium).Symmetry improvement was analyzed through measurements of bony landmarks,and clini-cal efficacy was comprehensively evaluated.Results All surgeries were successful,with primary healing achieved upon discharge.No cases exhibited injury to the inferior alveolar nerve and vessels,unexpected fractures,or required secondary surgery.No serious complications oc-curred,and all patients were satisfied with the treatment outcomes.Measurements indicated significant improvement in facial symmetry a-mong all 15 patients,with statistically significant differences between preoperative and postoperative values(P＜0.01).Conclusion For pa-tients with facial asymmetry,combining BSSRO with mandibular angle contouring surgery effectively improves symmetry in the mandibular angle region,demonstrating favorable clinical outcomes.In cases of mandibular angle width asymmetry,partial outer-cortex resection or interpositional bone grafting between the inner and outer cortices may be considered.This one-stage strategy enhances corrective efficacy while avoiding secondary adjustments,providing an improved design strategy for treating facial asymmetry.