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后牙锁牙合]畸形一般需要通过拔牙手段才能得到有效矫治。结合临床，本文提出了以下矫治理念：（1）制定矫治计划时上下牙列尽可能选择正畸拔牙矫治；（2）欲矫治第二磨牙的错牙合]，应先拔除第三磨牙才能获得满意的疗效；（3）有时可直接拔除锁牙合]的第二磨牙，让第三磨牙自行调整至正常位置；（4）为消除咬合干扰，在矫治之前在前牙区放置一平面导板，有利于锁牙合]牙的快速纠正。

Treatment of posterior crossbite malocclusions by extraction therapy

Treatment of the posterior crossbite needs the extraction of some teeth thus it can get good results. The authors give some clinical ideas ： （ 1 ） It is the better way for us to choose the extraction therapy on the upper and lower dentitions; （2）To treat the 2nd molar malocclusion, first remove the 3rd molar; （3）Sometimes we can extract the malposition teeth, such as 2nd crossbite tooth and let the 3rd molar drift to the normal position automatically; （4）In order to avoid interrupting occlusions, use the bite-plate during treatment of the posterior crossbite malocclosions.