Periodontal pus overflow may be caused by periodontitis pus overflow, periodontal pocket pus overflow, apical periodontitis. 1. Pus overflow from periodontitis: patients do not pay attention to oral hygiene for a long time, and the surface of the teeth is infected by bacteria, which leads to the occurrence of periodontitis. Due to bacterial infection, cell necrosis, etc., pus is discharged between the patient’s tooth bed and the tooth. 2. Periodontal pocket overflow: Periodontal pocket is a structure formed after the destruction of periodontal tissues, if the periodontal pocket accumulates a large amount of tartar, plaque, etc., the leukocytes will produce a large amount of pus when they fight against the bacteria in the plaque, which will lead to the overflow of pus from the periodontal pocket. 3. Periapical inflammation: Periapical inflammation is a more serious oral disease, usually caused by inflammation of the pulp downward. Inflammation exists in the apical periodontitis, the patient’s gums will be congested and swollen, with the further development of the disease, pus may appear on the gums overflow situation. If there is pus overflowing from the periodontium, it is recommended to go to the dental hospital in time, under the guidance of the doctor for targeted treatment.