微植体支抗和多曲唇弓非拔牙矫治骨性Ⅱ类错的头影测量研究

Cepholometric study for Class Ⅱ Jaw′s malocclusion being treated nonextractedly in multiloop edgewise arch wire combined with microimplant anchorage

目的通过评价直丝弓技术结合微植体支抗和多曲唇弓非拔牙矫治骨性Ⅱ类错的牙颌面结构变化,初步探讨其矫治机制。方法 13例直丝弓技术结合微植体支抗和多曲唇弓矫治者为实验组,非拔牙设计;15例直丝弓矫治技术配合Ⅱ类颌间牵引矫治者为对照组,拔牙设计。两组均为矢状Ⅱ类、垂直均角骨面型,伴轻、中度牙列拥挤,年龄15～32岁(平均23.6岁)。应用SPSS17.0统计软件对两组矫治前后的头影测量变化值进行比较。结果实验组矫治后SNA、ANB角减小,SNB角增大,矫治前后变化差异有统计学意义(P<0.01);对照组矫治后U1-NA、L1-NB减小,U1-L1角和FMA角增大,矫治前后变化差异有统计学意义(P<0.05)。结论直丝弓技术配合微植体支抗和多曲唇弓技术可通过A点后退、上牙弓整体内收及在牙弓中获得间隙来矫治骨性Ⅱ类错并改善其矢状向不调,并有控制下颌垂直高度,利于下颌逆时针旋转和B点前移的作用。

Objective To explore the mechanism of dental and craniofacial changes in Class ⅡJaw＇s mal- occlusion being treated nonextractedly in straight wire arch technique with muhiloop edgewise arch wire and microim- plant anchorage. Methods Experimental group included 13 cases being treated nonextractedly in straight wire arch technique,using multi-loop edgewise arch wire and microimplant anchorage. Control group included 15 cases being treated extractedly in straight wire arch technique, using elastic pull of Class Ⅱ. All Cases were skeletal facial type of ClassⅡ and mandibular average angle, light or middle dentition crowding, 15 to 32 years old （average 23.6 years old）. Cepholometric values before and after treatment in two groups had been compared statisticlly in SPSS17.0. Re- suits Angles SNA, ANB were smaller and SNB was bigger in experimental group（P 〈 0. 01 ）, distances U1-NA, L1- NB were shorter and angles U1-L1, FMA were bigger in control group after treatment （P 〈 0. 05 ）. Conclusion Mech- anism for treatment effect in Class Ⅱ Jaw＇s malocclusion being treated nonextractedly in straight wire arch technique, using multi-loop edgewise arch wire and micmimplant anchorage were as follow： （ 1 ）Jaw＇ discrepancy in sagittal plane had been improved because point A and upper anterior dentition was moved posteriorly and adequate space could be obtained. （2）Controlling the mandibular plane angle benefited mandibular rotation in counter clockwise and point B being moved forward.