Neurosensory Recovery Following Mental Nerve Skeletonization in Intraoral Open Reduction and Internal Fixation of Mandible Fractures.

PURPOSE: The purpose of this study was to evaluate neurosensory recovery after mental nerve skeletonization in open reduction and internal fixation (ORIF) of mandible fractures.

METHODS

This was a prospective nonrandomized observation study of adult subjects treated at a Level I trauma center between April 1, 2016 and December 31, 2019, with mental nerve skeletonization for ORIF of mandible fractures. Age, sex, and mandibular injury severity score (MISS), and functional sensory recovery (FSR) and subjective neurosensory recovery of skeletonized mental nerve were recorded at preoperative and regularly scheduled follow-up appointments. Uninomial and multinomial logistic regressions were conducted with a significance level of < 0.05.

RESULTS

Twenty-six subjects (all male) completed all the postoperative protocol requirements and were included in this study. All subjects had a loss of FSR (S0) and subjective neurosensation immediately after surgery. Half of the subjects achieved FSR (S3) and subjective neurosensory recovery (VAS < 4) an average of 42 days after surgery. All subjects improved FSR (S4) by 57 days and subjective neurosensory recovery by 90 days after surgery. These were independent of MISS but had decreased recovery time with increased age. No incidences of mental nerve neuropathic pain during the trial period were found.

CONCLUSIONS

FSR and subjective neurosensory recovery from mental nerve skeletonization in intraoral ORIF of mandible fractures was achieved in all subjects by the end of this study. Neurosensory recovery was independent of MISS but decreased with increased age. Initial inverse correlations between objective and subjective neurosensory assessments were insignificant at study completion. No incidences of neuropathic pain were identified during the time of this study. Mental nerve skeletonization in ORIF of mandible fracture may be performed with an anticipated return of functional and subjective neurosensory recovery within 3 months of surgery.