Gingival scraping, known medically as “subgingival scraping”, is a treatment for periodontal disease, but the process of scraping may involve the risk of bleeding and bacteremia from damage to the gingival mucosa. Subgingival scraping is the use of a relatively fine subgingival scraper to scrape away the calculus and plaque located on the root surfaces of the periodontal pockets in order to treat periodontal disease. There is no harm in doing it correctly and mastering the indications. However, a few patients may have the following risks: 1. Gingival mucosal injury and bleeding: for manual scraping, the clinical operation requirements are high, the operation is rough or not standardized easily lead to gingival injury and bleeding. 2. Bacteremia: when scraping, bacteria pass through the damaged gingival mucosa, and there is a risk of bacteremia. If the patient also suffers from nephritis, diabetes or heart disease, the risk of bacteremia will also increase. If subgingival scraping is needed, it is recommended to choose a regular medical institution. In the subgingival scraping operation bleeding more, after the operation can be appropriate under the guidance of the doctor with antibiotics to prevent infection or local application of periodontal plugging agent treatment.