多曲方丝弓技术矫治恒牙期偏矫治的颌变化的研究

Research of cranio-occlusional change of arch asymmetry malocclusion in permanent dentition treated by the multiloop edgewise arch wire technique

目的通过对比治疗前后的X线头影测量,分析通过多曲方丝弓(缩写为MEAW)技术矫治恒牙期偏畸形治疗前后颌的变化,了解MEAW矫治技术矫治恒牙期偏畸形的机理。方法本次研究应用0.018×0.025托槽系统治疗的恒牙期偏畸形病例共10例。结果L6-Xi减少,L6/MP增大,U6/FH减小,U6/PP减小,PNS-U6’(mm)的减小均表示上下磨牙各自均向远中倾斜、远中移动,颌骨变化较小。结论①MEAW治疗恒牙期偏病例,主要是通过牙齿的移动和牙槽骨的改变而完成的,骨组织变化是有限的。②MEAW纠正偏畸形,是由于在对侧使用短Ⅲ类牵引,使对侧下磨牙的明显直立、远中移动,偏侧则采用短Ⅱ类牵引,偏侧上磨牙远中倾斜、移动,使磨牙关系得到明显改善。同时纠正前牙中线不齐。

Objective To compare craniofacial and occlusional changes of permanent dentofacial asymmetry before and after multi - loop edgewise archwire （MEAW） therapy, and analyze the mechanism of asymmetry correction by MEAW. Methods 0. 018×0. 025 bracket system was applied to treat 10 eases of permanent dentofacial asymmetry. Results L6/FH increaed, while 1.6 - Xi, U6/FH, U6/PP and PNS - U6＇ （mm） deceased significantly, which indicated the distal tipping and movement of upper and lower molars, no obvious changes on jaws. Conclusion ①Tooth movement and alveolar rebuilding lead to MEAW asymmetry correction, however, little changes on jaws. ②Short Ⅱ elastic is used on asymmetry side to gain distal tipping and movement of upper molars, while short Ⅲ elastic on the other side to tip and move the lower molars distally, molar relationship and midline diastema are treated.