The painful swelling of the flesh at the very back of the innermost tooth is commonly considered to be the imminent eruption of a wisdom tooth, resulting in periapical swelling, i.e. wisdom tooth pericoronitis. It may also be acute periapical and periodontitis caused by the swelling of the surrounding tissue, it is recommended to go to the stomatology clinic to clarify the cause of treatment. 1, wisdom tooth pericoronitis: most due to incomplete eruption of wisdom teeth, there will be swelling of gum tissue, severe pain in the posterior tooth area, serious cases will appear to eat, swallowing pain aggravated phenomenon. You can take oral penicillin drugs combined with metronidazole to reduce inflammation, and apply chlorhexidine solution and saline to repeatedly rinse the blind pocket. If there is local abscess formation, incision and drainage should be made and drainage strips placed to avoid the spread of inflammation. You can also wait for the inflammation to be controlled and then surgically extracted for complete treatment; 2. Acute periapical infection: there will be swelling of the tissues around the tooth, and as the inflammation increases so that the affected tooth has the symptoms of floating sensation and continuous throbbing pain, the pulp cavity needs to be opened and drained in the acute stage to relieve the pain. Root canal treatment is performed to remove inflammatory pulp and necrotic tissue, and to fill it; 3, gingivitis or periodontitis: usually caused by bacterial invasion of periodontal tissues in plaque or food embedding, there will be periodontal abscesses, bad breath and other symptoms. It is possible to apply supragingival scaling and subgingival scraping to remove tartar, treat food embedding and fill cavities, and apply nitroimidazole and tetracycline anti-infection drugs as prescribed by the doctor, and also apply local chlorhexidine acetate solution to rinse, and after the inflammation is controlled, it is feasible to guide tissue regeneration and dental implant treatment.