开畸形为上下颌部分牙齿在正位及非正中　位在垂直向无接触。在临床上多见于恒牙期。开畸形 ,不仅切牙无切割和咀嚼功能 ,影响语言及面部美观 ,严重者面部下 1/ 3高度增大 ,上下唇不能闭合 ,开口呼吸 ,上呼吸道受累 ,影响健康。开　虽较少见 ,但治疗却比较困难 ,有些病 Open deformity for the upper and lower jaw part of the teeth in the positive position and non-median position in the vertical contactless. Clinically more common in permanent dentition. Open the deformity, not only incisors without cutting and chewing function, affecting the language and facial appearance, in severe cases under the face 1/3 height increases, the upper and lower lip can not be closed, open breathing, upper respiratory tract involvement, affecting health. Although less common, but the treatment is more difficult, some diseases