There are various forms of oral and maxillofacial deformities, mainly skeletal and dental deformities: 1. Skeletal deformities: Skeletal deformities are diseases caused by the development of the jaws, for example, some people’s upper jaws develop too protruding, and they will behave as buck teeth. Some people’s jaws develop too protruding, which is called geodontia. Some people’s jaws grow crooked, crooked to the left or crooked to the right, resulting in obliquity, all of which are collectively called jaw malformation. 2. (a) the most common have teeth uneven, generally because too many teeth, can not be in the jawbone under the row, that is, the row of teeth under the deformity. (2) The malformation that the jawbone has more teeth and the teeth have less gap, that is, the malformation with more teeth. (3) The upper row of teeth is more protruding than the lower row of teeth, or the lower row of teeth is more protruding than the upper row of teeth, which is also a type of malformation. (4) The arch of the upper row of teeth is narrower than the arch of the lower row of teeth, which will cause the back teeth (teeth together). (e) The upper and lower rows of teeth are not aligned, because the upper and lower rows of teeth are misaligned to the left or to the right, which is called a deviation. In a word, in addition to the general classification of malocclusion, there is also the classification of age group. For example, there are malocclusion during the period of tooth replacement and adult malocclusion after adult. Another kind of malocclusion is the acquired malocclusion, for example, if a tooth is lost, the tooth next to it will fall down, and after it falls down, it will cause unfavorable bite, which is also called malocclusion, and it needs to be corrected by orthodontics before implantation, and only then can we do implant restoration.