Bilateral sagittal split osteotomy (BSSO) is a widely used surgical technique that is used to treat mandibular deformity. This thesis investigated BSSO with splitter and separators. The... Show moreBilateral sagittal split osteotomy (BSSO) is a widely used surgical technique that is used to treat mandibular deformity. This thesis investigated BSSO with splitter and separators. The occurrences of common complications and their risk factors are assessed. BSSO was performed according to the Hunsuck modification with splitter and separator without the use of chisels. Retrospective analysis of more than 250 patients was performed. BSSO performed with the splitter-separator technique was found to be associated with a low mean incidence of permanent hypoaesthesia of 9.9% per patient. Age was a significant risk factor for hypoaesthesia with marked differences between age groups (<19 years: 4.8%; 19-30 years: 7.9%; >30 years 15.2%). The incidence of bad split was 4.0% per patient. The intra-operative presence of third molars significantly increased the risk of bad split. Infection occurred in 15.1% of patients. Removal of bicortical screw osteosynthesis material because of symptoms was indicated in 4.9% of patients. Relevant risk factors for complications are age (hypoaesthesia) and the presence of third molars during surgery (bad split). Show less