Facial Palsy can have several causes, varying from congenital, idiopathic, traumatic or due to an after-effect of an oncologic surgery and otitis media.
The most frequent one is the idiopathic palsy or else called Bell Palsy. It occurs due to the edema of the facial nerve inside the Facial canal in the Temporal bone.
Bell palsy assaults one in every thirty people during their life-time. There are studies showing that complete recovery happens in most cases. In the remaining ones there is a partial recovery with significant after-effects and the older the patient, the worse improvement can be.
The techniques most used nowadays to refresh the paralyzed face are the cross-face nerve graft and the transposition of the temporalis muscle, the neurorrahphy between the hypoglossal nerve and the damaged facial nerve and the microsurgical transplant of the gracilis muscle.
For recent paralysis, we prefer the cross-face nerve graft with the end-to-side neurorrhaphy. That means to put one or two grafts of the sural nerve connecting the normal facial nerve to the paralyzed one without splitting any of the face nerves up.
In older cases, we use the orthodromic transposition of the temporalis muscle.
Therefore, in order to smile the patient makes a small movement as of biting, contracting the temporalis muscle and so pulling the corner of the mouth up in a smile-like movement. In the same way, in congenital paralysis this orthodromic transposition of the temporalis muscle can also be used.
One of the most serious situations is the Moebius Syndrome, a kind of congenital paralysis that is bilateral. In these cases we have been also using the orthodromic transposition of the temporalis muscle.