Chronic/Persistent Idiopathic Facial Pain. 
Persistent or chronic idiopathic facial pain, often called atypical facial pain, is often used as a diagnosis of exclusion.  It is chronic pain in a nonanatomically distributed area of the face and mouth that can be episodic or continuous and described as a nagging dull pain that at times is severe.  It is associated with other chronic pain conditions, psychological abnormalities, and significant life events.  Investigations are all normal and early treatment can prevent chronicity.  A multidisciplinary biopsychosocial approach with the use of antidepressants and cognitive behavior therapy provides the best chance of pain relief and improved quality of life.