The fifth cranial nerve is one of the most important nerves in your body. It carries all of the sensations from your face, including pain and temperature. Because it passes through the middle ear, it also carries sound information from your eardrum to your brain.
Trigeminal neuralgia is a disorder of the fifth cranial nerve. It causes extreme pain in one part of the face, typically on one side of the jaw or cheekbone. The pain can last for hours at a time and comes in waves, with periods where you feel fine between episodes. The pain can be accompanied by changes in sensation, such as tingling or numbness; facial muscle twitching; or even drooping or paralysis on one side of your face if the nerve is damaged enough to lose its connection to the brainstem and spinal cord.