Impact of different lingual split patterns on inferior alveolar nerve recovery after bilateral sagittal split osteotomy in patients with skeletal class III malocclusion.

This study investigated the impact of different lingual split patterns on inferior alveolar nerve (IAN) recovery following bilateral sagittal split osteotomy (BSSO). Patients with skeletal class III malocclusion who underwent BSSO between April 2021 and December 2023 were included. Lingual fracture lines were categorized into four types using the Lingual Split Scale (LSS). Nerve recovery in the chin and lower lip was assessed through monofilament detection, and dual logistic regression was used to analyze the relationship between lingual split patterns and IAN recovery. Among the 114 lingual fracture lines, those in the LSS2 group had the highest incidence of neurosensory disturbance (40 %), significantly higher than in the LSS1 (12.82 %) and LSS3 (9.52 %) groups. Regression analysis showed that LSS3 did not impact IAN recovery, while LSS2 was identified as a significant risk factor. The findings suggest that surgeons should aim for an LSS3 pattern, because it does not affect IAN recovery and may reduce postoperative relapse, thereby improving outcomes in orthognathic surgery.