Periapical periodontitis does not heal with medication. Periapical periodontitis is an inflammation that occurs in the periapical tissue of the tooth. In most cases, periapical inflammation develops from pulpitis, where inflammatory material from the pulp reaches the outside of the root tip through the apical foramen and causes infection of the periapical tissue. Although the periapical tissue has a strong healing ability and the lesions in the periapical tissue can repair themselves, the prerequisite is that the source of infection must be cleaned up, so it is impossible to cure periapical infection completely with medication. In order to completely cure periapical infection, we must remove the infected material from the root canal system, i.e. we must do root canal therapy to completely remove the infected material from the root canal system, seal in the anti-inflammatory drug and then tightly fill the root canal to prevent reinfection, so that periapical infection can be slowly cured.