Posttraumatic and postsurgical sensory disturbance is a known complication of almost all zygomaticomaxillary (ZMC) complex fractures involving the infraorbital nerve, for which few treatments are effective. Our study used neurosensory assessments to evaluate the efficacy of melatonin on pain and nerve healing following ZMC surgery. Sixty-four randomly allocated ZMC fracture patients were prophylactically administered either oral melatonin or an identical placebo for 15 consecutive days. Pre- and postsurgical clinical parameters included subjective pain, numbness, and objective neurosensory function. Melatonin significantly reduced subjective pain perception in the early postoperative days, with a significant difference in VAS scores between the groups from postoperative day 3 (p = 0.048) until day 7 (p = 0.002). The VAS assessment of subjective numbness perception showed significantly lower self-perceived neurosensory disturbance for patients in the interventional group from the first month (p = 0.039) until the third month (p = 0.005). Objective neurosensory assessment using the pinprick test and two-point discrimination showed statistically significant improvement to almost normal sensation by the first month (p = 0.014) to fully normal sensation by the third month (p = 0.001). The study findings suggest that the prophylactic administration of melatonin confers significant clinical benefits in terms of reduced postoperative pain and improved sensory recovery.

BACKGROUND: Post-traumatic trigeminal neuropathy (PTN) can have a substantial effect on patient well-being. However, the relation between the neuropathic symptoms and their effect on psychosocial functioning remains a matter of debate. The purpose of this study was to evaluate the association between objective and subjective assessments of neurosensory function in PTN and predict neurosensory outcome using baseline measurements.
METHODS: This prospective observational cohort study included patients diagnosed with PTN at the Department of Oral and Maxillofacial Surgery, University Hospital Leuven, Belgium, between April 2018 and May 2020. Standardized objective and subjective neurosensory examinations were recorded simultaneously on multiple occasions during the follow-up period. Correlation analyses and principal component analysis were conducted, and a prediction model of neurosensory recovery was developed.
RESULTS: Quality of life correlated significantly (P < 0.05) with percentage of affected dermatome (ρ = - 0.35), the presence of brush stroke allodynia (ρ = - 0.24), gain-of-function sensory phenotype (ρ = - 0.41), Medical Research Council Scale (ρ = 0.36), and Sunderland classification (ρ = - 0.21). Quality of life was not significantly correlated (P > 0.05) with directional discrimination, stimulus localization, two-point discrimination, or sensory loss-of-function. The prediction model showed a negative predictive value for neurosensory recovery after 6 months of 87%.
CONCLUSIONS: We found a strong correlation of subjective well-being with the presence of brush stroke allodynia, thermal and/or mechanical hyperesthesia, and the size of the neuropathic area. These results suggest that positive symptoms dominate the effect on affect. In patients reporting poor subjective well-being in the absence of positive symptoms or a large neuropathic area, additional attention towards psychosocial triggers might enhance treatment outcome. The prediction model could contribute to establishing realistic expectations about the likelihood of neurosensory recovery but remains to be validated in future studies.

OBJECTIVE: To investigate the longitudinal resolution of neurosensory deficit (NSD) and the possible risk factors that might contribute to NSD following mandibular orthognathic procedures.
METHODS: A prospective longitudinal observational study on patients who had mandibular orthognathic procedures was performed. Standardized neurosensory assessments were performed. The 2 years longitudinal resolution and risk factors of NSD including patients\' age and gender, specific mandibular procedures and surgeons\' experience were analyzed.
RESULTS: 66 patients (44 females) with 132 sides of mandibular procedures were enrolled in the study. Surgical procedures included mandibular ramus surgery, anterior mandibular surgery, or the combination of the two. The overall occurrences of subjective NSD improved from 78.8% at postoperative 2 weeks to 13.8% at post-operative 2 years. Combinations of ramus surgery and anterior mandibular surgery increased the risk of NSD at the first three post-operative months (p < 0.05). Patients\' age and gender, and surgeons\' experience were not found to be risk factors of NSD after mandibular orthognathic surgery.
CONCLUSIONS: The occurrence of NSD after mandibular orthognathic procedures reduced progressively within the post-operative 2 years. Combination of mandibular ramus surgery and anterior mandibular surgery increased the risk of NSD in the early post-operative period.