Feasibility of a cross-face reconstruction of the mental nerve-A cadaveric simulation study with histomorphometric analysis.

Introduction: The inevitable sacrifice of the inferior alveolar nerve during oncologic resections results in substantial sensory impairment, impacting crucial functions such as speech, saliva retention, and mastication. This study investigated the feasibility of sensory restoration through cross-face reconstruction of the mental nerve via a contralateral mental nerve branch.

Methods: The cross-face reconstruction procedure was simulated in five formalin-fixed cadavers in both sides to evaluate the anatomic fundamentals and the nerve gap between the mental nerve main trunk and transferred contralateral mental nerve branch. Furthermore, a histomorphometric analysis was performed to assess the cross-sectional area and axon counts.

Results: The mean gap distance between the main mental nerve trunk and transferred contralateral branch was 15.3 mm. End-to-end coaptation was achieved in nine out of ten simulations. The mean cross-sectional area was 0.996 mm at the main mental nerve trunk and 0.253 mm at the coaptation site of the nerve branch. The mean donor-to-recipient axon ratio was found to be 0.3:1.

Conclusion: The cadaveric simulation demonstrates the feasibility of a cross-face reconstruction of the mental nerve with only minimal gapping. Advantages of the proposed technique include the use of shorter nerve grafts, to minimize donor site morbidity and enable fast reinnervation. This technique may offer a promising method to enhance the quality of life in patients by increasing survival rates and life expectancy.