Periodontitis is known as a silent killer lurking in the mouth, and its long-term presence can cause the following hazards: 1. Periodontitis damage in the oral cavity is mainly manifested by gum recession, periodontal abscess, resorption of alveolar bone, which can eventually lead to loosening, displacement and even loss of teeth; 2. Periodontitis local infection can act as a focal point that can cause an increased chance of disease in other important organs of the body, such as coronary heart disease, myocardial infarction and stroke. It can cause bacterial endocarditis, increase the chances of preterm delivery in pregnant women, and is closely related to diabetes and rheumatoid arthritis. Therefore, periodontitis should be treated as early as possible and should not be delayed for a long time, and standardized, professional periodontal treatment should be performed.