Inferior alveolar nerve transection (IANT) is a severe complication of sagittal split osteotomy (SSO). This study aimed to retrospectively evaluate the long-term sensory recovery in patients who experienced intraoperative IANT compared to those who did not.

This retrospective cohort study reviewed patients who underwent SSO from 2016 to 2022. Patients were divided into Group A (with IANT, 11 sides) and Group B (without IANT, 151 sides). Sensory perception was assessed using the Semmes-Weinstein (SW) test, static two-point discrimination (s-2PD) test, and a Numerical Rating Scale (NRS) at preoperative baseline and at 1, 3, 6, and 12 months postoperatively. Mann-Whitney U and Dunnett’s tests were used for statistical analysis (p < .05).

Group A demonstrated significantly worse sensory outcomes than Group B on all tests at all postoperative time points (p < .01). In Group B, SW and s-2PD values were significantly worse than baseline at 1 and 3 months but showed no significant difference at 6 and 12 months. In contrast, Group A outcomes remained significantly impaired compared to their own preoperative baseline throughout the 12-month follow-up.

Complete IANT during SSO, even with immediate nerve repair, results in a substantial and long-term persistent neurosensory deficit. While patients without nerve transection typically recover baseline sensory perception by 6 months, those with IANT experience only minimal improvement and remain significantly impaired at a year post-surgery.