Factors influencing neurosensory disturbance after bilateral sagittal split osteotomy: retrospective analysis after 6 and 12 months.

Objective The aim of this study was to analyze several factors regarding their possible influence on neurosensory disturbance (NSD) of the inferior alveolar nerve (IAN) after bilateral sagittal split osteotomy (BSSO). Study Design We investigated the possible influence of sex, age at the time of surgery, total operating time, intraoperative nerve encounter, advancement versus setback, fixation method, additional genioplasty, side, and region (lower lip vs. chin) on subjective neurosensory outcome a half-year after surgery. Results of a battery of neurosensory testing methods are also presented; 103 out of the initial 128 patients were available for further follow-up 1 year after surgery. Results Normal subjective sensibility was found in 74.6% and 77.2% of the regions after 6 and 12 months, respectively. Multiple regression models revealed significant effects of age, region, and total operating time after 6 months, and significant effects of age, region, and sex after 12 months. Conclusions NSD of the IAN after BSSO is influenced by age, total operating time (at 6 months), and sex (at 12 months). Significantly higher rates of NSD were found in the chin region.