One of the causes of root inflammation is periapical periodontitis, which is treated by root canal therapy. Root canal therapy is divided into three main steps: first, removing the decayed tissue of the tooth under local anesthesia, opening the pulp cavity, unblocking the root canal and sealing in the tooth nerve inactivation drug; second, removing the infected pulp, preparing the root canal for shaping and sealing in the calcium hydroxide anti-inflammatory drug; third, using the tip of the dental cement and hot dental cement with vertical pressure Thirdly, the root canal is tightly filled and the crown of the tooth is restored by using vertical pressure of the adhesive tip and hot cement. Through the above steps, the source of infection in the root canal is eliminated and the inflammation in the root tip is gradually absorbed by the body until it heals. Another cause of root infection is chronic periodontal disease, which is treated with a series of serial periodontal treatments including ultrasonic scaling, periodontal scaling, root planing, and periodontal flap surgery.