The trigeminal nerve is a branch of the cranial nerve. There are 12 pairs of cranial nerves, the fifth of which is called the trigeminal nerve. The trigeminal nerve originates from the pontine part of the brainstem and emanates from the pontine brain and is located in the frontal part of the face, as well as in the maxilla and mandible. Trigeminal nerve innervates facial sensation, and disorders of the trigeminal nerve can lead to facial pain, sensory sensitivity, and hyperalgesia. Trigeminal neuralgia is commonly associated with burning and irritation-like pain, and can also be associated with hyperalgesia and dullness of sensation throughout the face, forehead, maxilla and mandible. Causes include inflammation of the trigeminal nerve, such as brainstem lesions affecting the part of the trigeminal nerve that initiates it, which can cause trigeminal nerve damage. Clinically, trigeminal nerve disorder is first examined for brainstem lesions, and if there are no lesions, it is simply peripheral trigeminal nerve damage.