The treatment options to restore the smile in cases of long-standing complete facial paralysis are limited. A long-standing complete paralysis is generally felt to be one which is present for greater than 1 year. This definition is clinically useful although somewhat arbitrary.

In such cases, in order to restore a dynamic smile, one may perform a regional muscle transfer or free tissue transfer. Free tissue transfer, such as a gracilis free flap, can be an excellent option for many patients. It does, however, require multiple stages, an extended period of recovery prior to movement and has some morbidity at the donor site.

Regional muscle transfer generally comes down to a choice between the uses of temporalis and masseter muscle. The temporalis muscle tends to be preferred due to the ideal vector of pull. Most surgeons have employed a technique that transfers the muscle origin from the temporal fossa to the oral commissure. This requires passing the muscle over the zygomatic arch. The facial morphology is thus adversely affected by the protrusion of tissue around the arch and the depression created in the temple.

An alternative technique instead uses the insertion of the muscle—the temporalis tendon. The temporalis tendon transfer allows effective elevation of the oral commissure without alteration of the facial morphology. The tendon and coronoid process are released and transferred to the oral commissure. I prefer a minimally invasive temporalis tendon transfer (MIT3), in which a single incision is performed for a 1-hour procedure. I have found this a reliable and simple method or restoring oral symmetry and movement (Fig. 47.1).

The causes of facial paralysis are many and beyond the scope of this chapter. It is important to determine via the history if the facial nerve is intact. The facial nerve is often intact in cases of complete facial paralysis after acoustic neuroma resection. The reconstructive surgeon must communicate with the resection team, as well as the patient, about the options for timing of reconstruction. In cases of an anatomically intact nerve, often, the key distinction is the duration and extent of the paralysis. The temporalis tendon transfer is typically considered an option in the case of long-standing complete paralysis. In such cases, alternatives such as nerve transfers are not considered a viable option due to the facial muscle atrophy and fibrosis.

Advantages of the MIT3 procedure include that it is a relatively simple, one stage, minimally invasive procedure that produces results quickly. This is in contrast to free tissue transfer, which is typically a two-stage operation that requires a significant donor site and extended recovery period prior to any dynamic movement being achieved. Disadvantages include the lack of spontaneous mimetic movement and the relatively reduced excursion of the oral commissure in comparison to successful free tissue transfer with gracilis muscle.

The patient’s age, health status, need for adjunctive treatments such as external beam radiation, and personal preferences for reconstruction all play an important role in the decision-making process. The patient must be provided a realistic portrayal of the available options, which in these cases are limited to free tissue transfer, regional muscle transfer (including the minimally invasive temporalis tendon transfer, or MIT3), or static sling. Each has markedly different expectations and postoperative course, and one must educate the patient fully to help him/her to make the best decision.

It is ideal if the patient can be trained to do the temporalis smile prior to surgery. Most patients have weeks to months to work on the coordination of the temporalis muscle contraction with a contralateral elevation of the oral commissure.

I have the patient stand in front of a mirror, with his/her hand on the temple of the paralyzed side. The teeth are clenched enough to create a palpable bulge of the temporalis muscle as a zygomaticus smile is performed on the contralateral side. The duration is varied, but in each run, the goal is to hold the temporalis in contraction for as long as the contralateral oral commissure is elevated. The patient is advised to perform this in front of the mirror multiple times daily, for as many weeks as possible leading up to the surgical procedure.

The facial anatomy is analyzed carefully to assist in the decision of whether to perform the procedure via a transfacial versus transoral route. It should be noted that I have performed this procedure for over a decade and have found that the melolabial incision is quite favorable if meticulous attention is paid to the tissue handling and closure. I generally prefer to perform the procedure via a transfacial incision when a noticeable crease or fold is present on the contralateral side. If this is not the case, a transoral approach is used.