If the teeth wrong (malocclusion) deformity is not corrected, may cause oral local or even systemic hazards, mainly including the following aspects: 1, affect the teeth (malocclusion) surface development: because in the process of children’s growth and development, due to the wrong (malocclusion) deformity of the existence of the teeth (malocclusion) surface will have a direct impact on the normal development of the hard and soft tissues of the teeth (malocclusion) surface; 2, affect the oral health: due to crowding of misalignment of teeth can not be self-cleaning, and Easily occur caries and gingival, periodontal disease; 3, affect oral function: for example, the front teeth can cause abnormal pronunciation, posterior teeth shrinkage will relatively affect the chewing function, serious mandibular protrusion can cause swallowing difficulties, etc.; 4, affect the appearance of the face: for example, the open lip and teeth, the maxillary protrusion, the long face and the short face of the deformity, etc.; 5, resulting in systemic hazards: malocclusion is not only a localized harm to the teeth and the surface, but also to the whole body. Harmful, and the whole body may also cause harm. Such as chewing function is reduced, resulting in indigestion and gastrointestinal diseases. In addition, due to the deformity of the face, the patient can cause serious psychological and mental disorders.