The trigeminal nerve includes sensory and motor branches. In lesions of the motor branch, patients mainly present with masticatory motor or mouth opening motor deficits. In the case of lesions of the sensory branch, it clinically includes the ophthalmic meridian, maxillary nerve and mandibular nerve. Lesions of the ophthalmic nerve mainly manifest as numbness of the forehead, nasal roots of the upper eyelids, skin, and also nasal cavity, frontal sinus, lacrimal gland, cornea, etc., and sensory disturbance of the mucosa. In the case of a lesion of the maxillary branch, the patient presents with skin sensory disturbances between the lower lid and the orofacial fissure, but also at the mucous membranes of the maxillary teeth, gums, hard palate, and soft palate, with abnormal sensation. If the lesion is in the mandibular branch, it is manifested as abnormal sensation in the lower jaw and teeth, gums, the first 2/3 of the tongue, and the mucous membrane at the bottom of the mouth, and various discomforts such as pain and numbness can occur.