During the tooth replacement period, new teeth usually come in within one to three months after the loss of milk teeth. The exact timing varies depending on the child’s physical condition and dietary habits. Around the age of six, children begin to enter the period of tooth replacement. Under normal circumstances, milk teeth fall out and permanent teeth erupt. In some cases, the milk teeth do not fall out, and the permanent teeth have already erupted on the lingual side of the milk teeth. This situation is called retained milk teeth, and it is necessary to remove the milk teeth as soon as possible, so that the permanent teeth can be returned to their normal position. If the milk teeth fall out earlier, it is normal that the permanent teeth have not erupted for a short period of time, you can take an apical radiograph of the teeth, as long as there is a permanent tooth embryo and the eruption path of the teeth is normal, you can gnaw on more hard food to stimulate the eruption of the teeth. It is normal for new teeth to erupt within three months after the loss of milk teeth, if necessary, you can go to the dentist.