Periodontal is a class of topical slow-release drugs previously used in the clinic, the main ingredient is metronidazole, and the doctor takes a small section and puts it into the patient’s periodontal pocket during treatment, and after it releases the drug ingredients slowly in the pocket, it can play a bactericidal role. Currently, most of the ointment or film-like products such as Pailio are put into the periodontal pockets to control the formation of plaque, which belongs to the treatment of periodontal disease with local medication. However, these drugs cannot be purchased in the market or pharmacies and need to be purchased and used under the guidance of a professional periodontist.