Derringer K
Orthodontic Department, Eastman Dental Hospital, London.
Br J Orthod. 1990 May;17(2):89-99. doi: 10.1179/bjo.17.2.89.
Absolute distal movement of upper first molars together with distal tipping, but no significant extrusion, occurred with cervical traction. Distal movement of the maxillary first molars was more stable in the group where maxillary 2nd molars had been extracted. With Andresen treatment a restraining effect took place on the upper molars, while mesial movement of the lower first molars contributed to correction of the molar relationship.
上颌第一磨牙在颈部牵引时发生绝对远中移动并伴有远中倾斜，但无明显伸长。在上颌第二磨牙已拔除的组中，上颌第一磨牙的远中移动更稳定。采用安德雷森矫治器对上颌磨牙有抑制作用，而下颌第一磨牙的近中移动有助于磨牙关系的矫治。
