The incisors did not fall inside and grow new teeth, it is recommended to go to the hospital in a timely manner to take pictures to check whether the teeth are retained, milk teeth retained need to be removed in a timely manner, according to the situation of the later consideration of orthodontics. 1. The incisors did not fall out, and the milk teeth inside grow out, often because the diet is too refined, not enough to stimulate the milk teeth root resorption and fall out, or due to the milk teeth dental disease caused by the difficulty of falling out, the formation of milk teeth stagnation. Permanent teeth erupt abnormally from other parts of the mouth. When the diagnosis is confirmed, it is necessary to go to the hospital immediately for extraction of milk teeth. 2. When the milk teeth are extracted, the permanent teeth will gradually return to the normal growth position, if the extraction is too late, the teeth with serious malocclusion need to be considered for orthodontic treatment after the completion of replacement teeth.