Immediate Inferior Alveolar Nerve Reconstruction With Ablative Mandibular Resection Results in Functional Sensory Recovery.

BACKGROUND

Ablative mandibular resection with sacrifice of the inferior alveolar nerve (IAN) results in loss of sensation and decreased quality of life.

PURPOSE

The purpose of this study is to evaluate functional sensory recovery (FSR) of immediate IAN allograft reconstruction performed during ablative mandibular resection at 1 year following surgery.

STUDY DESIGN, SETTING, SAMPLE: This is a single-center retrospective cohort study that included consecutive subjects who underwent mandibular resection with IAN discontinuity and used a nerve allograft of ≥40 mm.

PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE: The primary predictor variable is the use of an immediate nerve allograft in mandibular reconstruction.

MAIN OUTCOME VARIABLE(S): The main outcome variable is FSR at 1 year using the Medical Research Council Scale.

COVARIATES

Covariates include subject age, sex, specific pathology, nerve gap length, and development of neuropathic pain.

ANALYSES

Statistical analysis of comparison of neurosensory outcomes was measured by bivariate statistics, weighted values, repeated measures, analysis of variance, and McNemar test.

RESULTS

The study sample was composed of 164 subjects, of whom 55 (33.5%) underwent nerve allograft reconstruction and 30 (18.3%) did not have nerve reconstruction. Seventy-nine subjects (48.2%) did not meet the inclusion criteria. In the entire nerve allograft group of 55 subjects, FSR was achieved in 80% at 1 year; however, in benign disease alone, 31 of 33 (94%) achieved FSR at 1 year. In the nonallograft group (all benign disease), only 2 of 30 (7%) achieved FSR at 1 year. The significant covariates were age and pathology. Benign pathologic resections were 5.2 times more likely to achieve FSR than malignancies, and all subjects ≤ 18 years of age achieved FSR. After adjusting for age, sex, pathology, nerve gap length, nerve allograft was significantly associated with achieving FSR at 1 year (adjusted odds ratio = 5.52, 95% confidence interval = (1.03, 29.51), P value = .045 < .05).

CONCLUSION AND RELEVANCE

Immediate long-span IAN allograft reconstruction is effective in restoration of sensation with an overall 80% of subjects achieving FSR at 1 year, while benign disease resulted in 94% FSR at 1 year. Immediate IAN reconstruction should be considered with mandibular resection involving the IAN, especially for children and benign disease.