Gum swelling and pain, accompanied by facial swelling and lymph node enlargement may be caused by acute apical periodontitis, the treatment has to take pain medication, incision and drainage of pus, root canal treatment, etc., specific as follows. 1. Taking painkillers: such as diclofenac sodium, meloxicam, ibuprofen, etc., which can have a certain effect on relieving the pain symptoms, and the drugs should be used under the guidance of the doctor. 2. Incision and drainage of pus: When acute periapical inflammation develops to the stage of subperiosteal or submucosal abscess, incision and drainage of pus can be made under local anesthesia, and rubber drainage strips can be placed. The pulp cavity can be opened at the same time to help relieve pain and drain pus. 3. Root canal treatment: Periapical inflammation needs to be thoroughly controlled by root canal treatment, through root canal preparation, root canal disinfection and root canal filling, in order to promote the healing of periapical lesions. It is recommended to go to the hospital in time to receive regular treatment as soon as possible.