The term for scaling, or periodontal scaling, means that the dentist uses various instruments, such as ultrasonic scaling machines and scalers, to remove soft and hard substances attached between the neck of the teeth and the gum sulcus to ensure the health of periodontal tissues and teeth. The so-called soft material refers to plaque, which is due to a mixture of food debris, cellular epithelium and bacteria that clings to the teeth. It not only causes bad breath, but also secretes many enzymes and toxins that damage the teeth and surrounding tissues, causing tooth decay and gingivitis. As for hard material, it refers to calculus, which contains calcium, phosphorus, cellular epithelium, bacteria, etc. It forms a hard mass that clings to the teeth and not only decomposes toxins, but also presses on the normal gum tissue, causing inflammation and bacterial infection. Therefore, it is important to rely on dental scaling to remove calculus and avoid sequelae such as periodontal disease. It is recommended that everyone receive a biannual oral health examination and scaling. Periodontal scaling is divided into supragingival scaling and subgingival scaling. Generally, the first scaling a patient receives is supragingival scaling, which is to clean the calculus and plaque above the gums; if the periodontal disease is serious and the periodontal pockets are deep, most of them have to receive subgingival scaling after about a week, which is to remove the tartar and granulation tissue under the gums with a scraper to restore periodontal health and control the progress of periodontal disease. It is best to take appropriate oral antibacterial agents and mouthwash application on the day after scaling to prevent and control the occurrence of bacteremia.