Children’s tooth replacement usually starts around the age of six, and parents should be reminded that at the age of six, in addition to the lower front teeth starting to be replaced, a permanent tooth will grow directly on the posterior side of the milk molar, which is the sixth age tooth, and a total of four teeth will grow on the upper, lower and left side. During the period of tooth replacement, parents are recommended to take their children for a routine oral examination once every six months. If abnormal teeth are found to erupt, we should analyze the cause and take necessary intervention measures, and at the same time, we can also protect the newly erupted teeth through fluoride or sulcus closure.