Vulval sealant treatment of children’s teeth can effectively prevent the occurrence of sulcular caries. For milk teeth, it is generally recommended that children aged 3-4 years old should have their milk molars closed, children aged 8-9 years old should have their sixth molars closed, and children aged 11-12 years old should have their second molars closed. When doing the closure, special emphasis should be placed on the child’s cooperation, and the child should be able to cooperate well with the wetting treatment and cleaning of the tooth surface. If the surface of the teeth is not well insulated, the sealant will fall off easily and thus will not have the effect of preventing tooth decay. When the child cooperates well, the surface of the sulcus should be inspected and treated carefully. For the sulcus caries with tooth decay, fillings should be carried out, but not sulcus closure treatment, which is the place where special attention should be paid to sulcus closure. If the shallow caries is closed, it may cover up the original caries and cause the further development of caries. Therefore, before doing the fossa closure, we must carefully check whether the caries has already occurred, and at the same time do a good job of reassuring the child, and do a better job of isolating the wet. In addition, after doing the fossa closure, it is recommended to review regularly every half year or so whether there is caries occurrence and whether there is sealant loss. If there is any loss of sealant, it is possible to re-treat the sulcus. For the treatment of smooth surface of teeth, fluoride can be applied to prevent the occurrence of dental caries, and the gutter closure mainly has a good preventive effect on the occurrence of gutter caries.