The sixth tooth is the first permanent tooth that erupts during a child’s tooth replacement. The six-year-old teeth (clinically known as first molars) erupt around the age of six weeks and are located behind the second molar; many parents neglect to protect them because they may not have lost their milk teeth at the time of eruption. Since the six-age teeth play an important role in maintaining the normal occlusal relationship between the upper and lower jaws and erupt earlier, it is important to treat them in time to avoid affecting the children’s chewing function and the normal development of the jaws. Usually, we must do a good job of oral care, maintain oral hygiene, regular dental checkups, and after the eruption of the six-age teeth, we can carry out fissure sealing to prevent the occurrence of dental caries.