Hello, generally speaking, private hospitals calculate tooth cleaning according to the whole mouth, which is about 100 to 200, while general public hospitals calculate it according to the number of teeth, which is generally tens of yuan. The whole process includes cleaning and polishing the supragingival and subgingival oral cavity under ultrasound, and finally applying drugs in the periodontal pocket. Dental calculus is a local stimulating factor in the oral cavity, and long-term existence may lead to inflammation of periodontal tissue. If it exists for a long time, it may also lead to the decrease of periodontal tissue adhesion, lead to the loosening of teeth, and finally lose the chewing function. It must be pulled out and cleaned once every six months to one year.