正畸治疗后稳定性探讨

Long-term stability of orthodontic treatment out of retention

目的 探讨影响正畸治疗后稳定性的相关因素。方法 采用PAR (peerassessmentrating)指数对 74例错畸形患者正畸治疗后 2～ 8年 (平均 5 0 0 5个月 )的治疗前后及保持后模型进行评估分析。结果 (1)保持后 ,加权总分值的复发率为 13 0 1% ,牙齿排列、覆盖、覆和后牙段横向关系复发率分别为 6 38%、15 5 6 %、2 8 86 %和 2 2 4 1%。 (2 )保持后明显改善者从治疗后 77 0 3%减至6 4 86 %。PAR分值增加 5 3例 ,分值不变 6例 ,分值减少 15例。 (3)Begg矫治器保持后加权总分值大于方丝弓矫治器 (P <0 0 5 )。 (4)安氏Ⅱ类错保持后牙排列和总分值大于I类错 (P <0 0 5 )。 (5 )不对称拔牙组保持后加权总分值大于其他组 (P <0 0 1)。结论 (1)保持停止后 ,牙齿有回复到原来位置的倾向。牙齿排列、覆盖、覆和后牙段横向关系复发较明显。 (2 )正畸治疗后的稳定性与矫治器。

Objective To investigate the correlative factors influencing the stability of orthodontic treatment out of retention. Methods Pre treatment, post treatment and 2～8years out of retention study models of 74 cases with malocclusion were assessed by the PAR (Peer Assessment Rating) index. Results (1) Out of retention, the relapse rate was 13 01% in weighted PAR total scores and the relapse rate was 6 38%, 15 56%, 28 86%, 22 41% in alignment, overjet, overbite and transverse buccal occlusion respectively. (2) The rate of great improvement was decreased from 77 03% after treatment to 64 86% out of retention. The PAR score increased in 53 cases (71 62%), unchanged in 6 cases (8 11%) and reduced in 15 cases (20 27%) out of retention. (3) The weighted total scores in the Begg appliance were higher than that in Edgewise out of retention ( P < 0 05). (4) The alignment and PAR total scores out of retention were higher in classⅡmalocclusion than in class I malocclusion ( P < 0 05). (5) The weighted PAR total scores post retention were higher in unilateral extraction than in other groups ( P < 0 01). Conclusions (1) There was a trend that teeth relapsed to original position out of retention. The relapse rate was greater in alignment, overjet, overbite and transverse buccal occlusion. (2) The stability out of retention was not related to patient′s age and sex, but was related to the types of appliance, malocclusion and extraction.