Dental calculus is deposited on the surface of the teeth plaque and soft dirt calcification of the formation of dental stone, hard texture, the color is yellowish brown or brown. 1. Usually do not pay attention to dental hygiene, no proper brushing, will let plaque long-term residue in the tooth surface, long time will appear calcification formation of dental calculus. Calculus can lead to gum redness, swelling, bleeding, oral odor and other symptoms, triggering gingivitis. 2. Dental calculus can be removed by ultrasonic scaling, which uses ultrasonic technology to remove small dental calculus and residual plaque and pigment on the surface of the teeth. Before the ultrasonic scaling operation, you need to use 3% hydrogen peroxide liquid rinse, which can effectively prevent cross-infection. In normal life, we should pay attention to oral hygiene and cleanliness, learn the correct way of brushing teeth, rinse after meals; the appearance of dental calculus should go to the stomatology department in time for professional treatment.