Whether or not the extraction of a baby tooth will affect the permanent teeth below depends on the specific tooth position and age. If the milk teeth that are close to the period of permanent teeth replacement are suffering from caries, it is possible to consider removing them, for example, if the upper incisors or lower incisors are decayed in a child of more than 6 years old, it is possible to consider removing the milk teeth directly, and it will not have much effect on the permanent teeth below, because the permanent teeth will be erupted soon. However, if this is not the case, and the baby teeth are still relatively early in the tooth replacement period, the extraction will have a certain impact on the permanent teeth, because there is no space for the corresponding teeth after extraction, and the surrounding teeth will be tilted to the side of the gap, resulting in no space for the eruption of the permanent teeth below, and the formation of obvious crowding of the teeth. In this case, it is usually necessary to make a gap retainer for the gap after the extraction of milk teeth to expand the space and then wait for the permanent teeth to erupt from below.