There are many patients who request orthodontic treatment for malocclusion will say that they are “blunt teeth”, which is not aesthetically pleasing. In fact, the common people say that the “blunt teeth” is a kind of tooth arrangement deformity, mainly manifested as the upper front teeth protrude forward, too much tooth exposure, according to the traditional aesthetic point of view is considered unattractive. So what exactly is the cause of the “blunt teeth”? According to clinical research, it is usually caused by abnormal development of teeth and bones. The protrusion of the upper front teeth is mainly due to an excessive lateral tilt of the teeth, which is different from the normal alignment of the teeth, and sometimes the lower front teeth are also tilted outward. For example, excessive vertical development of the maxilla, which carries the upper front teeth, can cause excessive exposure of the teeth; excessive anterior and posterior development of the jaws can cause protrusion deformity, so the “foundation” for the teeth to grow is excessively protruding, which naturally causes the teeth to protrude, and at the same time can It also causes the protrusion of the lips. Abnormal jaw development and tooth alignment often occur at the same time, resulting in what is known as “bruxism” and “picking teeth”. In terms of etiology, genetics is an important cause, as the alignment of teeth, bone development, and facial shape development generally receive genetic information from relatives. In addition, bad habits during childhood may also lead to protruding teeth, such as sucking fingers, biting foreign objects, etc. Under the influence of long-term bad habits, the growth of teeth and bones will be affected to a certain extent, and after puberty, it may cause malformation of teeth or bones. However, for malocclusion with skeletal development, orthodontics alone may not be able to completely correct the malformation and orthognathic surgery is required.