Trigeminal neuralgia, as the name suggests, is a thick intracranial nerve that comes out of the skull and divides into three branches: the upper branch manages skin sensation around the eyes, the middle branch manages skin sensation in the upper jaw (upper lip, including the teeth of the upper jaw), and the lower branch manages the lower jaw (lower lip, including the teeth of the lower jaw). Trigeminal neuralgia is a painful condition caused by pressure, irritation and pulling of the trigeminal nerve root due to intracranial lesions. Trigeminal neuralgia occurs in middle-aged and elderly people, and its pain is characterized by being located on one side of the face (because both sides are managed by the left and right trigeminal nerves), with sudden onset and sudden cessation of pain. The pain can be pain in one of the three branches of the dominant area, such as simple pain in the lower jaw and lower teeth, or it can be pain in all three branches of the dominant area and pain on the whole side of the face. When the pain attacks, patients dare not chew food or even drink water, so patients often think it is a dental problem and blindly consult a doctor. If they go to an irregular clinic, they cannot distinguish it from trigeminal neuralgia and often treat it according to dental disease, which results in spending unjust money and suffering unjustly, but the disease does not improve. Therefore, if you suffer from pain on one side of the face, especially when it is pressure pain, you should think about whether the trigeminal nerve is to blame? Most of the trigeminal nerve pain is caused by sclerosis and tortuosity of intracranial blood vessels compressing the trigeminal nerve root, and a few patients are caused by intracranial tumor compressing the trigeminal nerve.