To learn about trigeminal neuralgia, it helps to know a little about how the affected nerves are laid out.
In your head you have 12 pairs of cranial nerves. The trigeminal nerves are among these pairs, and they let you feel sensations in your face. One nerve runs down each side of your head.
Each trigeminal nerve splits into three branches, controlling the feeling for different parts of your face:
- ophthalmic branch controls your eye, upper eyelid, and forehead
- maxillary branch affects your lower eyelid, cheek, nostril, upper lip, and upper gum
- mandibular branch runs your jaw, lower lip, lower gum, and some muscles you use for chewing
The disorder can affect any of the three nerve branches, meaning you could feel pain from your forehead to your jaw. More than one nerve branch can be affected by the disorder. Usually, you will feel pain on only one side of your face. Some people feel it on both sides. When that happens, it is called bilateral trigeminal neuralgia.