Matteson S R, Kantor M L, Proffit W R
Angle Orthod. 1982 Jan;52(1):11-8. doi: 10.1043/0003-3219(1982)052<0011:EDMOTM>2.0.CO;2.
A five-year study of 26,264 panoramic radiographs found distal positioning of the mandibular second bicuspid associated with a missing adjoining first molar in one of every 505 patients. Following early removal of the first molar, there is a 5% to 10% chance that the second bicuspid will migrate distally. It usually continues until it contacts the root of the second molar, and then rotates up into occlusion adjacent to the parallel with that tooth. Mesial drift seldom occurs in this circumstance; the resulting space between lower first and second bicuspids remains. Early conservative management can be very important in these cases, making periodic x-ray examination advisable whenever a molar has been lost and the adjoining bicuspid has not yet erupted.
一项针对26264张全景X光片的五年研究发现，每505名患者中就有1人下颌第二双尖牙向远中移位与相邻第一磨牙缺失有关。在早期拔除第一磨牙后，第二双尖牙有5%至10%的几率向远中迁移。它通常会持续迁移，直到与第二磨牙的牙根接触，然后向上旋转至与该牙平行并进入咬合。在这种情况下很少发生近中漂移；下颌第一和第二双尖牙之间会留下间隙。在这些病例中，早期保守治疗非常重要，每当一颗磨牙缺失且相邻的双尖牙尚未萌出时，建议定期进行X光检查。
