Basic periodontal treatment, periodontal surgical treatment and loose teeth fixation treatment can be carried out in the advanced periodontitis stage. 1. Basic periodontal treatment: mainly includes supragingival scaling (e.g. ultrasonic scaling, sandblasting, etc.) and subgingival scaling, which can effectively remove tartar or calculus and other inflammatory stimuli adhering to the tooth surface. 2. Periodontal surgery: mainly refers to periodontal flap surgery, that is, the use of surgical removal of deeper periodontal pockets in order to promote the healing of periodontal tissues; such as periodontal tissue damage is serious when the teeth can not be retained, the teeth can be considered to be extracted. 3. Loose teeth immobilization: loose teeth can be temporarily or permanently periodontal splinting, which can effectively maintain the stability of the teeth in order to utilize them to exercise normal chewing functions. It is recommended to actively seek medical advice and follow the doctor’s instructions for examination and treatment.