Comparison of neurosensory disturbance after using preoperative cone-beam computed tomography and panoramic radiography to locate the inferior alveolar nerve in bilateral sagittal split ramus osteotomy.

Inferior alveolar nerve (IAN) injury is the most common side effect of bilateral sagittal split ramus osteotomy (BSSRO), often caused by anatomical variability and the proximity of the nerve to the buccal cortex. This study was performed to compare functional sensory recovery (FSR) times when using cone-beam computed tomography (CBCT) vs panoramic radiographs (OPG) preoperatively to locate the IAN in patients undergoing BSSRO. A split-mouth randomized design was used. Twenty patients who underwent BSSRO in the Faculty of Dentistry, Mahidol University, between January 2023 and July 2024 were included. CBCT and OPG images were obtained preoperatively. Subjective and objective neurosensory evaluations were performed preoperatively, immediately postoperative, and at 1, 3, 6, and 9 months postoperative. The median time to FSR in the lip area was 2 days in the CBCT group and 35 days in the OPG group (P = 0.050; borderline significant difference), while in the chin area it was significantly shorter in the CBCT group (CBCT 2 days vs OPG 63 days; P = 0.026). Patients subjectively reported more neurosensory disturbances when compared to the FSR results (lip and chin region, both P < 0.001). Neither the IAN-to-buccal cortex distance nor the magnitude of the mandibular movement was significantly associated with time to FSR in either the lip or chin area (all P > 0.05). CBCT appears to be a useful modality to support safer surgical approaches, promote faster sensory recovery, and enhance patient satisfaction following BSSRO.