(Tic Douloureux) Pain in the trigeminal nerve, chief sensory nerve of the face and the motor nerve enabling chewing. A disorder of the trigeminal nerve producing bouts of severe, lancinating pain lasting seconds to minutes in the distribution of one or more of its sensory divisions, most often the mandibular and/or maxillary. The cause is uncertain. Recently, at surgery or autopsy, arterial and ( less often) venous loops have been found compressing the trigeminal nerve root at its entry point into the brainstem, which suggests that tic is essentially a compressive neuropathy. Adults usually are affected, especially later in life. The pain is often set off by touching a trigger point or by activity (e.g. chewing or brushing the teeth). Although each bout of intense pain is brief, successive bouts may incapacitate the patient.