Assessment of a neurophysiological model of the mandibular branch of the facial nerve in rats by electromyography.

Objectives: Our objective was to develop an experimental model for the noninvasive and objective evaluation of facial nerve regeneration in rats using a motor nerve conduction test (electromyography).

Methods: Twenty-two rats were submitted to neurophysiological evaluation using motor nerve conduction of the mandibular branch of the facial nerve to obtain the compound muscle action potentials (CMAPs). To record the CMAPs, we used two needle electrodes that were inserted into the lower lip muscle of the rat.