It is very necessary for children to have their sockets closed. When the teeth just grow out, because the teeth themselves are not worn out, so the grooves, sockets and gaps of the teeth are deeper, at this time for oral cleaning, the bristles of the toothbrush can’t get into some grooves, and some sockets can’t be brushed, so the grooves and sockets are easy to keep food residues and can’t be cleaned well, and some children’s sockets start to blacken slowly, leading to the occurrence of dental caries. Therefore, we can take a method, that is, the sulcus closure, to close the deeper sulcus and sockets in time, then it is better to clean. For children with milk teeth, i.e. 3-4 years old, the sulcus can be closed. For children with permanent teeth who start to erupt around the age of 6 years old, sulcus closure is usually performed between the ages of 6 and 8 years. With the eruption of the second permanent molars, sulcus closure can also be performed by about 12 years of age.