Neurosensory Recovery Following Skeletonization of Mental Nerve During Open Reduction & Internal Fixation for Mandibular Fractures

Abstract

Background: Intraoral open reduction and internal fixation (ORIF) procedures used to treat mandibular fractures can result in neurosensory abnormalities due to soft tissue and nerve manipulation. While treating fractures located in the parasymphysis and anterior body regions, where the inferior alveolar and mental nerves are located, there is limited access which can impede correct reduction and hinder the use of optimal fixation. To counter these problems, better access can be gained through skeletonization of the mental nerve, which is known to result in neurosensory disturbances. However, the extent of neurosensory deficits that may result from these procedures and the degree of their recovery remain unknown in current literature. Objective: The primary purpose of our study was to evaluate and correlate the objective and subjective neurosensory recovery of the mental nerve following skeletonization during Open Reduction and Internal Fixation of mandibular fractures. Study Design: This was a prospective observational study. Settings: The adult subjects having mandibular fractures treated at Jinnah Hospital, Lahore Pakistan, a level III tertiary care hospital. Duration: The study duration was from July 1, 2022 and December 31, 2022. Methods: Demographic details were taken and preoperative objective and subjective neurosensory assessment was performed. Following surgery, postoperative objective and subjective neurosensory assessment was performed on post op day 1, after 1 and 6 weeks. Collected data was analysed with significance level of <0.05. Results: Twenty four subjects who completed regular follow-up visits for 6 weeks were included in this study. All subjects had objective or subjective neurosensory deficit preoperatively. Following surgery, all the subjects had FSR grade S0 and subjective loss of sensation at immediate postoperative assessment after surgery. 87.5% of the subjects had complete objective and subjective neurosensory recovery at the end of 6 weeks. There was a significant negative correlation between objective and subjective neurosensory recovery during the initial stages of the study, which became non-significant by the end of 6 weeks. Conclusion: Following mental nerve skeletonization during ORIF of subjects with mandibular fractures having some degree of preoperative paraesthesia, a majority of subjects achieved complete neurosensory recovery 6 weeks postoperatively. Therefore, it is expected for a skeletonized mental nerve to return to normal function within 2 months after ORIF for mandibular fractures.