Toothache, eye pain, and half of the face pain are usually caused by pulpitis, which is most often treated by opting for endodontic surgery. Root canal therapy is performed by removing the inflamed pulp and necrotic material from the root canal and performing mechanical preparation of the root canal wall. Disinfection of the root canal is required, and after disinfection a tight filling of the root canal is done to remove the root canal contents and produce a very good healing effect on the periapical tissue. Removal of undesirable irritation prevents the development of periapical lesions or promotes healing of periapical lesions. The main treatment steps are to open the pulp and enter the pulp chamber, clean the diseased pulp tissue, measure the length of the root canal, and then perform an extended flush, followed by disinfection and filling of the root canal, which can basically be done with a porcelain crown after filling tightly to ensure the resistance of the tooth. The toothache, eye pain and half of the face pain are usually due to trigeminal neuralgia carried by the dental pulp, accompanied by headache, eye pain and half of the face pain.