Do you have any information as to why there is a correlation with facial paralysis and dry mouth? I frequently see it with medications, but am now learning it often occurs in relation to permanent facial paralysis. Can you explain the association?
Facial paralysis affects the cranial nerve VII, also known as the facial nerve. The functions of the facial nerve are very complex; the motor fibers are responsible for innervation of all facial muscles, such as the frontalis, orbicularis oris, and others. It also has a sensory component, which is responsible for taste to the anterior two-thirds of the tongue, as well as tear and saliva production. Particularly, the submandibular and sublingual glands receive their parasympathetic innervation from the facial nerve.
One of the side effects of facial paralysis is dry mouth. This is most likely the result of the affected facial nerve on saliva production, but possibly could be related to drooling because of facial weakness.
Management of dry mouth related to facial paralysis should be treated in a fashion similar to methods of treatment for xerostomia. The general approach would be to offer symptomatic relief, and prevent oral complications as a result of dry mouth. Mechanical stimulation of the salivary glands with sugar-free chewing gum and topical therapy with artificial lubricants and mouth rinses are beneficial. Professional dental care and exposure to topical fluoride products should be utilized in order to prevent dental disease from occurring or progressing.