Abstract:

The congenital missing and impaction of the third molar is an important manifestation in modern people and appears in all kinds of oral malocclusion，due to the imbalanced degeneration in muscle，mandible and teeth. The orthodontists have paid great attention to the following questions：whether the existence or missing of the third molar affects the development of malocclusion and the relapse after orthodontic treatment，whether the eruption of the third molar is affected by orthodontic treatment and how to treat the third molar reasonably.

Key words: third molar, malocclusion, orthodontics

摘要：

第三磨牙先天缺失和阻生是现代人肌肉、颌骨和牙齿不平衡退化的重要体现，出现在口腔各类错牙合畸形中。第三磨牙的存在和缺失是否会影响错牙合畸形的形成和矫治后的复发，正畸治疗是否会影响第三磨牙的萌出，临床上正畸医生如何对第三磨牙进行合理取舍，这些问题为正畸医生所关注。

关键词: 第三磨牙, 错牙合畸形, 正畸