Dental caries is a chronic disease with high incidence, and it is reported that the caries rate of 5-year-old children’s milk teeth is 66%, and the untreated rate is 97%. The caries rate increases with the increase of age. The diet of infants and children is mostly soft food with strong stickiness and high sugar content, which can easily adhere to the tooth surface, and after fermentation and acid production, the hard tissues of teeth will be demineralized to form defects, i.e. dental caries. In addition, children sleep for a long time, the mouth is relatively in a static state, saliva secretion is reduced, the self-cleaning effect is poor, plus parents do not know enough about the importance of oral hygiene, and often do not brush their teeth before going to bed, so they are easy to suffer from dental caries. Tooth decay affects children’s chewing, often causes pain, not timely treatment can cause pulpitis, apical inflammation, some premature loss, not only affects the digestive function of children, but also affects the jaw bone development. The “six-age teeth” are the first permanent molars, which are the molars growing behind the milk teeth when the child is six years old and are not replaced for life, they are the teeth exercising the main chewing function, and are often mistaken by parents as the teeth of the milk teeth, and are often neglected and suffer from caries, and are often not treated in time after suffering from caries, resulting in the premature loss of the “six-age teeth “This will have a very bad impact on the growth and development of children. The “six-age teeth” are very important, should pay attention to protection, except brush the teeth carefully, can carry out sulcus closure or apply fluorine protection varnish regularly, in order to reduce the occurrence of dental caries.