Calculus cannot be brushed off by brushing. Calculus is a mineralized substance formed by plaque around the gums and requires ultrasonic shock scaling. The gingival calculus is divided into supragingival and subgingival calculus. The supragingival calculus can be cleaned by conventional scaling machines, while the subgingival calculus requires subgingival scraping treatment. The scraping instruments are either ultrasonic shock subgingival scraping instruments or manual scraping instruments, usually used in conjunction with gingival flaps if necessary, to remove the calculus under a microscope. This ensures an adequate fit between the teeth and the gums, and the teeth are more secure for oral hygiene and for the development of the oral flora. Usually it is recommended to use mouthwash to maintain the oral flora, mouthwash with compound chlorhexidine rinse or compound tinidazole solution.