Many people think that the upper and lower rows of teeth are exactly aligned to “fit” is the most standard state. This “alignment” is actually a kind of malocclusion, which belongs to the same category as the “envelope” where the lower teeth encircle the upper teeth, and requires corresponding orthodontic treatment. The misshapen jaw not only affects the chewing function, but also affects the appearance and psychology, and even damages the health of the temporomandibular joint, so it is advisable to deal with it early. The normal relationship between the upper and lower teeth should be the upper teeth partially wrapped around the lower teeth, and the distance between the front and back of the upper and lower rows of teeth is about 2 to 3 mm, and the height of the overlap between the upper and lower is about 3 to 4 mm, which is conducive to the cutting of teeth. This facilitates the function of the teeth and guides the bite, and also protects the joints. Some people have bad habits such as biting the lower lip or biting the finger because of congenital genetics or later in life, which leads to excessive “sky-bagging” and the distance between the front and back of the two rows of teeth is more than 4 mm, which is commonly known as “buck teeth” and “whistling teeth The “buck teeth” and “whistling teeth” are commonly known. She recommends that patients with mild “buck teeth” be fitted with braces for fixed orthodontic treatment, and now the invisible bracketless orthodontic treatment is also a good method, which is comfortable and does not affect the appearance and eating; patients with severe “buck teeth” need to be extracted for orthodontic treatment, and those who are very serious have to undergo Orthodontic – orthognathic surgery combined treatment. The “bungee”, where the lower teeth wrap around the upper teeth, is medically known as “anterior retrusion”. The “geodesic” is complex and can be divided into three categories – 1, bony: the patient’s lower jaw is overdeveloped, sometimes accompanied by underdevelopment of the upper jaw, resulting in abnormal bony position of the upper and lower jaw relationship, generally with family heredity. 2, dental: the upper and lower jaw bone morphology position is normal, but the teeth grow into this, may be due to bad feeding habits or love to spit out the tongue, bite the upper lip and other habits. 3.Functional: Mostly caused by local occlusal interference factors, sometimes resulting in skewed teeth. Some people suffer from rhinitis for a long time, the airway is not open, only open mouth breathing, disrupting the balance of oral muscle strength, if in the growth and development period, will lead to underdevelopment of the upper jaw, can not keep up with the normal development of the lower jaw; there are also people who have one side of the “ground” and one side of the “ground “The reason may be that one side of the bite interference, or rotten teeth or periodontal disease, resulting in long-term chewing only with the other side of the teeth, and over time the teeth and facial asymmetry. “This can affect the bite and the cutting function of the teeth, as well as the temporomandibular joint, which also affects the aesthetic and social appearance of the face. In terms of treatment, Ai Hong recommends that patients with a genetic predisposition to bony “geodontia” wait until growth has stopped, usually after the age of 18, to be evaluated by a doctor to determine if orthognathic surgery is needed. In contrast, early orthodontic treatment is recommended for dental and functional “geodontia” to restore the normal growth environment, and children with mouth breathing habits are advised to go to the hospital for consultation and correction at the age of 3. Children should go to the hospital for examination at the age of 7 to correct the bad habits, treat rhinitis, fill teeth, and adjust the treatment according to the cause, in order to prevent or reduce the occurrence of dental and jaw The occurrence of malocclusion plays a half-hearted role. Before the age of 14 for girls and 16 for boys, the upper arch can be enlarged with an arch expander to match the upper and lower arches, and then fixed for 3 months. If the best time for treatment is missed, or if the deformity is severe, the patient should consider orthognathic surgery after growth has stopped at age 18. The two rows of upper and lower teeth that fit neatly together may appear to be abnormal, and according to Hong Ai, this can be classified as “diastema”, which can cause interference with the bite of the back teeth, causing not only tooth wear, but also damage to the temporomandibular joint. Therefore, early diagnosis is needed. Many people think that the most standard state is for the upper and lower rows of teeth to “fit” in perfect alignment. This “alignment” is actually a dental malformation, and the lower teeth wrapped around the upper teeth of the “envelope” belongs to the same category, need to do the corresponding orthodontic treatment. Experts pointed out that malocclusion not only affects the chewing function, but also affects the appearance and psychological, and even damage the health of the temporomandibular joint, it is advisable to deal with early.