Factors predicting neurosensory disturbance after bilateral sagittal split ramus osteotomy: a retrospective cohort study.

Neurosensory disturbances (NSD) are the most widely recognized complication of bilateral sagittal split ramus osteotomy (BSSRO), but predictors of NSD remain unclear. The aim of this study was to identify factors predicting NSD following BSSRO. A retrospective cohort study of 129 consecutive patients with dentofacial deformities (median age 24.0 years; 76.0% female), who underwent BSSRO (95 without genioplasty, 34 with genioplasty), was conducted. The presence of NSD was evaluated at 6 months postoperatively and was found in 97 patients (absent in 32 patients). Potential NSD-related factors investigated were age, sex, genioplasty, mandibular canal type, inferior alveolar nerve (IAN) exposure, mandibular movement, and laterality. Multivariate binary logistic regression analysis was conducted to elucidate factors predicting NSD, with calculation of odds ratios (OR) and 95% confidence intervals (CI). The dependent variable was defined as NSD after BSSRO. Independent variables were those with P < 0.100 in the univariate analysis. In the multivariate binary logistic regression analysis, NSD showed a significant association with BSSRO with genioplasty (adjusted OR 3.87, 95% CI 1.21-12.26; P = 0.022) and left IAN exposure (adjusted OR 4.69, 95% CI 1.49-14.73; P = 0.008). The study findings may lead to enhanced clinical outcomes for BSSRO.