A new experimental model for studying peripheral nerve regeneration in dual innervated facial reanimation

Abstract

Background: Donor nerve selection is a crucial factor in determining clinical outcomes of facial reanimation. Although dual innervation approaches using two neurotizers have shown promise, there is a lack of evidence-based comparison in the literature. Furthermore, no animal model of dual reinnervation has yet been published. This study aimed to establish such a model and verify its technical and anatomical feasibility by performing dual-innervated reanimation approaches in Wistar rats.

Methods: Fifteen Wistar rats were divided into four experimental groups and one control group. The sural nerve was exposed and used as a cross-face nerve graft (CFNG), which was then anastomosed to the contralateral buccal branch of the facial nerve through a subcutaneous tunnel on the forehead. The CFNG, the masseteric nerve (MN), and the recipient nerve were coapted in one or two stages. The length and width of the utilized structures were measured under an operating microscope. Return of whisker motion was visually confirmed.

Results: Nine out of the eleven rats that underwent surgery survived the procedure. Whisker motion was observed in all experimental animals, indicating successful reinnervation. The mean duration of the surgical procedures did not differ significantly between the experimental groups, ensuring similar conditions for all groups.

Conclusions: Our experimental study confirmed that the proposed reanimation model in Wistar rats is anatomically and technically feasible, with a high success rate, and shows good prospects for future experiments.

Keywords

axonal regeneration / cross facial nerve graft / dual innervation / facial palsy / facial reanimation / neurotization

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2025 The Author(s). Animal Models and Experimental Medicine published by John Wiley & Sons Australia, Ltd on behalf of The Chinese Association for Laboratory Animal Sciences.