Bell's palsy

Bell's palsy is a form of facial paralysis resulting from a dysfunction of the cranial nerve VII (the facial nerve) causing an inability to control facial muscles on the affected side. Often the eye in the affected side cannot be closed. The eye must be protected from drying up, or the cornea may be permanently damaged, resulting in impaired vision. In some cases denture wearers experience some discomfort. The common presentation of this condition is a rapid onset of partial or complete paralysis that often occurs overnight. In rare cases (<1%), it can occur on both sides resulting in total facial paralysis.