“Toothed” and “Baotian” are a kind of common malocclusion in children in China, which is medically known as “retrognathia”, i.e. Anserine class III malocclusion. Reversal has a serious impact on oral function, facial aesthetics and psychological health, and gradually aggravates with the patient’s age. So, why does a child have a “circumcision”? What are the factors that will induce children to appear “circumcised”? 1, genetic factors “circumcision” has obvious family tendency, nearly half of the patients one to three generations of blood relatives (such as parents, grandparents, grandma and grandpa, aunts, aunts, uncles and so on) have a similar situation exists. Some genetic syndromes can also appear as “geoblasts”, such as cranio-clavicular hypoplasia syndrome, Crouzon syndrome, Rieger syndrome. 2, congenital diseases: cleft lip and palate, congenital megatongue, congenital absence of maxillary teeth can cause “parietal” 3, acquired causes Acromegaly, rickets often cause “parietal”; chronic tonsillitis, adenoid hyperplasia, enlargement of the pelvis caused by Mandibular protrusion, the formation of “parietal”; milk teeth caries untreated, premature loss of maxillary milk incisor due to trauma and other reasons, premature loss of milk molar or milk incisor delayed retreat caused by the permanent teeth in the lingual side of the long out, milk cusp wear insufficient, may cause the child “parietal”; oral bad habits, bad habits, bad habits, bad habits and bad habits. “Bad oral habits: often sticking out the tongue, biting fingers, biting the upper lip, habitually stretching the chin forward, and incorrect posture when the child is fed formula in early childhood can all cause “pericoronitis”; Treatment of “pockets of teeth” To treat “Hooded Teeth”, we need to find out the cause and treat the symptoms in order to stabilize the effect and prevent recurrence.