高角和低角病例的诊断、临床特征及正畸治疗特点(15)

低角病例腭平面、牙 合平面和下颌平面接 近平行, 下颌角呈直 角, 下颌下缘平缓, 下 颌管弯曲, 前牙直立, 上下中切牙角较大 the palatal plane, occlusal plane and mandibular plane nearly parallel to the angle of mandibular perpendicular to the flat edge under the lower jaw. Angle between long axis of upper and lower incisor is large.