When there is a hole on the top of a child’s tooth, it is usually a case of tooth decay or cavity. In the early stage of tooth decay and cavity, there is only a shallow layer of enamel and enamel layer of tooth decay, and there is no clinical symptom yet, so the child only shows a hole on top of the tooth, and it does not produce pain and other symptoms yet. At this time, the child should be given a filling as soon as possible, and do a good job of reassuring the child and carrying out the filling treatment. Early caries can be filled conservatively, preserving the pulp filling, as long as the decayed tissue is removed and then prepared into a special cavity type, the filling treatment can be carried out. If it continues to develop and spreads to the dentin layer or even affects the pulp, it will produce pain and other symptoms and bring further difficulties to the treatment. Therefore, we should take our children to have regular oral examination to find out early caries in time, and fill the teeth in time, and at the same time, we should do a good job of oral hygiene and eat less snacks and sweets to prevent and control the development of caries.