The only effective way to treat pulpitis is root canal treatment. Therefore, after the tooth nerve is injured by tooth decay and causes severe pain, you should go to the hospital for root canal treatment of the affected tooth. Root canal treatment requires 2-3 follow-up visits, and the whole course of treatment takes about 2-3 weeks to be fully treated. Root canal treatment is divided into 3 steps: 1) remove the infected hard tissue under local anesthesia, open the pulp chamber and seal in the nerve inactivation medication. 2) clean and disinfect the root canal, prepare the root canal system and seal in the root canal with calcium hydroxide type anti-inflammatory medication. 3) use the vertical pressure filling method of hot glue The root canal is filled tightly and the defect is then restored.