Tooth wear refers to the gradual loss of tooth hard tissue mainly caused by mechanical friction. In the normal physiological chewing process, with the increase of age, the balanced physiological hard tissue loss between the occlusal surface and the adjacent surface of teeth is called physiological wear. Because it is difficult to quantify the normal loss in clinic, it is suggested that the loss rate that may damage pulp survival or cause other complications of patients can be considered as pathological. Tooth wear can be divided into physiological wear and pathological wear. In physiological wear, the degree of physiological wear of tooth tissue is commensurate with age, and vertical wear of teeth can be compensated by bone hyperplasia and passive eruption of tooth apex. There are different reports about the physiological wear of enamel: some scholars report that it is about 29 (20 ~ 38) microns per year, but others think that the wear can be achieved only in half a year. Clinically, some factors often cause uneven or excessive wear of individual teeth or a group of teeth, or even the whole teeth, which is pathological wear. Remove the causes: such as changing bad living habits, adjusting occlusion, repairing missing teeth, and treating systemic diseases that cause tooth wear. Symptomatic treatment: dentin hypersensitivity caused by wear can be desensitized; The deep concave surface with serious wear of individual teeth and a gap between them and the opposite jaw teeth was treated by filling method to restore occlusal contact; High and steep points and wedge-shaped points caused by uneven wear have been adjusted and ground; Those who cause dental pulp, periapical disease or periodontal disease should be treated with corresponding dental pulp treatment or periodontal treatment. Severe tooth tissue defects can be repaired with onlay or full crown after endodontic treatment. Can many badly worn teeth be used? The gasket appropriately increases the distance between the jaws.