When tooth decay occurs and needs to be filled, the process of filling is mainly divided into three steps: 1, remove all the decayed tissue bacteria completely, generally need to apply dental handpiece for removal. 2, after the removal for the second operation, the cavity for filling. If the toothache is deeper and closer to the pulp tissue, a layer of calcium hydroxide material will be placed in the cavity first, and then the bottom will be placed on top, and zinc phosphate or polycarboxaldehyde zinc cement will be applied for filling, and finally the surface will be filled permanently, and silver mercury, composite resin or glass ion cement will be considered for filling. 3.The surface of the filling will be adjusted and polished, and generally the surface will be slightly raised after filling. The surface will be slightly protruding after the filling, the occlusal paper will be applied to determine the occlusal height, and then the handpiece will be applied for grinding afterwards, and polishing can be considered on the surface after the grinding.