正畸就是矫正牙齿、解除错牙和畸形。正畸主要研究错牙合畸形的病因机制，诊断分析及其预防和治疗，正畸可以达到美观牙齿的功效。口腔正畸学的英文名称来源于三个希腊词根的组合，它们的意思分别是“牙齿”“矫正”“学科”，即大家所说的“矫正牙齿”。
Orthodontics is to correct teeth, remove malocclusion and deformity. Orthodontics mainly studies the pathogenesis, diagnosis, prevention and treatment of malocclusion. Orthodontics can achieve the effect of beautiful teeth. The English name of Orthodontics comes from the combination of three Greek roots, which means "teeth", "orthodontics" and "discipline", that is to say, "orthodontics".
学术基础：
Academic basis:
1、颌骨的可塑性：颌骨，尤其是牙槽骨是人体骨骼中最活跃的部分之一。颌骨的改建包括增生和吸收两个过程，这是颌骨的重要生理特征，也是正畸治疗的基础，所以矫治过程中颌骨的变化主要是破骨与成骨的平衡的生理过程。
1. Plasticity of jaw: jaw, especially alveolar bone, is one of the most active parts of human skeleton. The reconstruction of jaw includes two processes: hyperplasia and absorption, which are the important physiological characteristics of jaw and the basis of orthodontic treatment. Therefore, the change of jaw in the process of orthodontic treatment is mainly the physiological process of balance between osteoclast and osteogenesis.
2、牙骨质的抗压性，在同液压钢坝  一正畸施力条件下往往只有牙槽骨的吸收，却没有或只有少量的牙骨质的吸收。
2. Under the same orthodontic force, the compressive strength of cementum is usually only absorbed by alveolar bone, but not or only a small amount of cementum.
3、牙周膜内环境的稳定性，正畸矫治完成后经过保持，牙周间的宽度、牙周膜与牙槽骨以及牙骨质的连接都能恢复正常。
3. After orthodontic treatment, the width of periodontal ligament, the connection between periodontal ligament, alveolar bone and cementum can be restored to norma