V to VII Nerve Transfer for Smile Reanimation.

Using the wording "facial reanimation," surgeons mean restoring movements to the paralyzed face. According to the condition of mimic muscle, facial palsy can be classified as recent (mimic muscle still alive) and chronic (atrophy of mimic muscle) palsy. The treatment is quite different because in the former group the mimic muscles can be still used so long as a new motor source would be connected to the damaged facial nerve. In the latter group, muscular transplantation is needed to substitute the atrophied mimic muscles of the middle part of the face. In both cases, the neural impulse that makes the muscles (mimic muscle in the former, transplanted muscle in the latter) move come from a new motor nerve. Nowadays, the masseteric nerve is widely used as a new motor source in recent facial reanimation; the same nerve has also a main role in the treatment of both chronic facial palsy where it is used as the new nervous stimulus for the new transplanted muscle and facial paresis where the nervous stimulus coming from the masseteric nerve is used to empower the stimulus coming from the injured facial nerve. The masseteric nerve can be usually connected directly to the facial nerve without the interposition of a nerve graft, with a faster reinnervation. Moreover, the use of the masseteric nerve gives no morbidity to the masticatory functions.