The caries of children’s milk teeth is common in molar caries and anterior molar caries, and the molar caries is often manifested as the caries of multiple tooth surfaces on one tooth at the same time, or the caries range is large; the anterior molar caries is often manifested as the ring caries of adjacent surface or lip surface. For children with a large range of molar defect, multiple tooth surface caries on one tooth, incomplete enamel development and caries susceptibility, preformed metal crown can be applied. The preformed metal crown can better restore the shape and chewing function of the child’s milk molar and promote the facial bone development of the child. It has been widely used in the restoration of children’s milk teeth in North America. Resin strip crown restoration is a technique for restoring a large area of defective premolar teeth and early childhood caries by inserting a composite resin into a celluloid crown restoration, and then placing the resin-filled crown over the tooth tissue.