(usually the masseteric nerve) in an end-to-end fashion. through an incision in front of the ear, the cheek flap is elevated below the underlying layer of fat. here the nerve stimulator can be used in identifying the donor motor nerve to the masseter muscle. once the nerve is identified, it is dissected from its connections and traced into the muscle to free as much length as possible. results all procedures in general show an improvement of symmetry of smile and patient satisfaction, although time of recovery differs between different approaches. primary neurorrhaphy provides the best possible outcome, as the anatomy and function of the damaged facial nerve is restored. after primary neurorrhaphy of the facial nerve mean recovery time typically is 6 to 12 months. the contraction amplitude after using a cfng is usually not very powerful, but it results in a relatively spontaneous smile because the contralateral healthy facial nucleus controls the movements. after a cfng procedure the first signs of reinnervation usually occur between 4 and 12 months. the use of the masseteric nerve provides an amount of movement that is within the normal range, resulting in a more symmetrical but not completely emotional smile. nerve transfers using the hypoglossal or masseteric nerves and the "babysitter" procedure result in first contractions of the mimic muscles after approximately 4 to 6 months. however, after the use of the hypoglossal nerve control of facial movements is hard to obtain by the patient and a spontaneous smile may not occur at all. true spontaneity of a smile will not occur at the same rate in all dynamic smile reconstructions. a spontaneous smile is smiling without consciously thinking about it. the primary neurorrhaphy and free muscle transfer are the only options to restore a true spontaneous smile. although the masseteric nerve transfer provides a strong smile within the range of normal, it never becomes truly spontaneous and emotional. but with practice, the majority of patients can provide a spontaneous smile some of the time due to the plasticity of the cerebral cortex. effective rehabilitation can also prevent biting whilst smiling, when using the masseteric nerve as nerve transfer. complications there are several complications, however, most patients find them less invalidating than the inability to smile. general postoperative complications are infection of the muscle donor site, facial abscess, hypertrophic scars, hematoma, and swelling of the face or muscle donor site. in some cases of incomplete facial paralysis, the procedure had a decline in function as a result. however, this improved after only a few months. almost all procedures show synkinesis, meaning involuntary movements appear during the voluntary movements. in primary neurorrhapy, with or without an interposition graft, perineural fibrosis is a common complication. with the use of the cfng there is a risk of sensory deficits in the lower part of the leg, due to the sural or sapheneous nerve graft. a complication seen with the use of the masseteric nerve is the inability to chew without the appearance of a smile. the hypoglossal nerve as a donor nerve can induce tongue atrophy due to denervation.