Hi! Welcome to HCM! The path of facial nerve is long and complex,so there are many causes that may result in facial nerve paralysis.The most common is Bell s palsy, the exact cause is unknown most probably due to viral infection. Bell s palsy causes sudden weakness in your facial muscles. This makes half of your face appear to droop. Your smile is one-sided, and your eye on that side resists closing. Although for most people, Bell s palsy is temporary. Symptoms usually start to improve within a few weeks, with complete recovery in about six months however as the symptoms are aggravating my advice is that you should get your wife examined by a neurologist. During the physical examination, a distinction will be made between paralysis and paresis (incomplete paralysis). paralysis is far more serious and requires immediate treatment. It must also be determined whether other nerves are involved in the motor defect or not. I sincerely hope this will help!