Of main consideration regarding the optimal management for a person with facial paralysis are the cause and duration of the paralysis. In cases of congenital (present since birth) facial paralysis, the facial nerve and facial muscles may not have developed appropriately or may be absent.Attempting to provide a new nerve source to these muscles, then, is not logical or possible, but other types of reconstruction are possible.nce a muscle has lost its nerve source for any reason, there is a window of opportunity to provide a nerve to those original muscles. After that window has passed, usually about 12-24 months, the original muscles can no longer accept a nerve. In those cases, a nerve supply as well as new muscle must be provided.