A Study on the Relapse change after orthodontic Treatment in skeleta class III with Reversed Occlusion.

为了确定复发发生在哪个阶段以及发生了什么样的变化，对诊断为骨骼逆转闭塞的患者（男性18例，女性12例）进行了首次检查时、积极治疗结束时以及保留1年和3年后的侧位x线头颅片进行了评估。实验结果如下：从完成积极治疗到保留1年期间的变化。1)骨骼系统：由于SNP的改变，观察下颌骨的突出运动。2)牙齿系统：l1 -下颌平面发生了一些变化，包括门牙在下颌骨上的倾斜。3)咬合平面：咬合平面无变化，处于稳定状态。保留1年至3年期间的变化1)骨骼系统由于SNB和SNP的变化，观察下颌骨的前突运动。2)牙系统：上门牙上唇偏斜，上门牙的上喷流和U1-SN发生变化。3)咬合平面角度咬合平面在稳定状态下没有变化。结果表明，正畸治疗后的复发现象为骨骼系统下颌骨前突运动和牙系统上、下门牙唇部倾斜，保留1年至3年期间sn -咬合平面角的变化减小。

In order to determine at which stage the relapse occurs and what kind of change is produced in patients (18 males and 12 females) diagnosed as skeletal reversed occlusion, lateral X-ray cephalograms obtained at the first examination, at completion of active treatment and after 1 and 3 year retention were evaluated.The results were as follows.1.changes during the period from completion of active treatment to 1-year retention.1) Skeletal system :Due to changes in SNP protrusive movement of the mandible was observed.2) Dental system :Some changes occurred in the L1-mandibular plane, including inclination of front teeth on the mandible.3) Occlusal plane :The occlusal plane showed no change in a stabilized state.2.Changes during the period from 1-year retention to 3-year retention1) Skeletal systemDue to changes in SNB and SNP protrusive movement of themandible was observed.2) Dental systemThere were changes in overjet and U1-SN with labial in clination of upper front teeth.3) Occlusal plane angleThe Occlusal plane showed no changes in a stabilized state.Those results indicate that the relapse phenomena after orthodontic treatment for reversed occlusion were mandible protrusive movement in the skeletal system and labial inclination of upper and lower front teeth in the dental system and SN-occlusal plane angle was decreased in change during the period from after 1-year to 3-year retention.