横腭弓增强支抗的研究

A study on a transpalatal arch for reinforcing anchorage

目的 :评价临床矫治安氏Ⅱ类 1分类错牙合病例使用横腭弓支抗的控制效果。方法 :选择 15～ 2 9岁安氏Ⅱ类 1分类错牙合患者 12例 ,分析用横腭弓增强支抗治疗前后的X线头影测量值的变化。结果 :① 6 Ptmo、6 So、6 CR So、6 AP So、1 Ptmo、1 So、1 NA、1 SN矫治前后改变极具显著性 (P <0 .0 0 1) ;② 6 PP于治疗后亦增大 ,有显著性 (P <0 .0 5 ) ,但是∠GoGn SN和ALFH/AFH的改变没有显著性 ;③横腭弓用于增强支抗时 ,磨牙前移量被控制在拔牙间隙的 1/3内。结论 :在常规治疗手段如Ⅱ类牵引及后牙段结扎固定的辅助下 ,横腭弓能够提供中到重度支抗 ;横腭弓能够对磨牙伸长进行较为有效的限制。

砄bjective: To evaluate the effect on a transpalatal arch on reinforcing anchorage. Methods: 12 cases with ClassⅡ Division 1 malocclusion were selected and treated with a transpalatal arch for reinforcing anchorage. Results: ①The forward displacement of the first maxillary molar (6 Ptmo, 6 So, 6CR So and 6AP So) , the backward displacement(1 Ptmo and 1 So ) and the reduction of the axial inclination (1 NA and 1 SN) of the upper incisors were increased( P <0.001);②The vertical distance of the first molar to the palatal plane (6 PP )was increased( P <0.05),but GoGn SN angle and ALFH/AFH were reduced insignificantly( P >0.05);③The forward displacement of the first maxillary molar was less than one third of the extraction space ( P <0.05). Conclusion: With Class Ⅱ elastic fixation of buccal segment ,the transpalatal arch can provide medium to maximum anchorage and can provide moderately effective restriction for the extrusion of the maxillary molars.