Trigeminal Neuralgia
There's a reason why some people call this the "Suicide" disease.  Periodic episodes of extreme facial pain that can rarely if ever be alleviated through medications would drive even the most sane individual to their potential breaking point.  Essentially, Trigeminal Neuralgia means pain originating from the trigeminal nerve, which is one of a group called the cranial nerves.  The trigeminal nerve supplies sensation to the face and controls the movement of your jaw muscles.  One patient once described the feeling of pain in these areas as being like a "pack of fire ants biting your face while your hands are tied behind your back." 
Upper Cervical care has been very successful in helping people overcome this condition by getting to the root of its origin.  The trigeminal nerve nucleus (the hub of that nerve) is based in the brainstem.  Given that removing irritation to the brainstem is the central premise behind Upper Cervical care and that the blinding pain associated with Trigeminal Neuralgia originates from the Trigeminal nerve based in the brainstem, then it simply makes sense that Upper Cervical care would be able to very likely address the cause of T.N.  If the Trigeminal nerve is being irritated at its hub in the brainstem, then trying to solve the problem by addressing the manifestations of pain in the face and jaw would be like fixing the windows and the roof when its really the foundation of the house that is the root of the problem. 
The forthcoming link will take you to a research study that was recapped on a website dedicated to Upper Cervical care. &con=&key=