Vulval sealant for sixth age teeth means to seal the sockets of sixth age teeth, that is, the first molar. Without removing the tooth tissue, a protective agent is applied to the sulcus on the tooth surface to protect the tooth enamel from bacteria and metabolites, thus preventing dental caries. Sixth-aged teeth are the teeth that bear the most important function of chewing, due to the early eruption, usually fully erupted at the age of 6-8 years old, if we do not pay attention to the protection, it is easy to get caries. Therefore, the sixth-aged teeth are the main target of gash closure. First of all, it is necessary to clean the tooth surface, acid etch the tooth surface with acid etching agent, and apply the sealant after rinsing and drying. After the sealing is done, regular review is needed to observe the retention of the sealant on the sixth-aged teeth, and if the sealant falls off, the sealing should be done again in time to prevent the occurrence of caries. In addition to doing gully closure, we can also prevent tooth decay by paying attention to oral hygiene everyday, brush teeth in the morning and evening, use soft bristle toothbrush and toothpaste for children, parents should teach children to master the correct way of brushing teeth. Pay attention to rinse mouth after eating snacks and fruits in daily life, do not eat sweet food again before going to bed, have oral examination regularly and treat tooth decay as soon as possible.