Six-year-old teeth generally refers to the first permanent molar, the first permanent molar is generally necessary to do the fossa sealing, can reduce its rate of caries and extend its use of time, as follows. Caries is a common oral disease, which is caused by demineralization and decomposition of dental tissues under the action of bacteria and other factors, and can cause dental defects or even tooth loss. The first permanent molars erupt earliest among the permanent teeth and exist in the oral cavity for the longest time, with more sockets and grooves on their surfaces, and children are mostly unaware of oral cleaning when they erupt, so the rate of caries is higher. Fossa sealing is a sealant coated in the fossa area of the teeth, which is easy to clean and resistant to bacterial erosion and destruction, and can effectively reduce the caries rate of the first permanent molar and protect the health of its dental tissues. It is recommended to go to the hospital to receive professional treatment.