Functional Reconstruction of Total Lower Lip Defects with a Radial Forearm Free Flap Combined with a Depressor Anguli Oris Muscle Transfer

Two total lower lip reconstructions were accomplished by combining a radial forearm free flap and a depressor anguli oris muscle transfer. The radial forearm flap was used to reconstruct the inner surface of the lower lip. The bipedicled musculofascial flap, which includes both depressor anguli oris muscles, the depressor labii inferioris muscles, and the mentalis muscles, was elevated onto the chin and sutured superiorly to the modioli to obtain innervated sphincter function. Good results were obtained both aesthetically and functionally. Electromyography revealed almost normal mobility of the depressor anguli oris muscles 6 months after the operation. No drooling was seen during mastication, and no air leakage was observed during puffing of the cheeks. This is an effective procedure for the reconstruction of the sphincter function of the lower lip.