Distal-Jet矫治器远中移动上颌磨牙的疗效

Distalization of maxillary molar by Distal-Jet appliance

目的:评价Distal-Jet矫治器远中移动上颌磨牙的疗效。方法:应用Distal-Jet矫治器对12例平均年龄为12.3岁,由于上颌磨牙前移所致的安氏Ⅱ类错患者进行治疗,通过远中移动磨牙前后的头影测量分析和模型测量分析评价其远中移动磨牙的疗效。结果:①磨牙平均向远中移动(3.6±0.75)mm,牙冠远中倾斜(3.5±3)°;②第一前磨牙近中移动(2.1±1.7)mm,牙冠近中倾斜(3.1±2.57)°,前牙覆盖增加(1.47±1.76)mm;③磨牙和第一前磨牙分别伸长(0.39±0.46)mm和(0.43±0.61)mm;④双侧上颌第一磨牙中央窝间宽度增加(2.8±1.1)mm。结论:Distal-Jet矫治器能有效地整体远中移动上颌磨牙,但也会引起少量前磨牙的近中移动及牙冠近中倾斜。

Objective：To evaluate the clinical effects of Distal-Jet appliance on the distalization of maxillary molar. Methods： 12 Class II malocclusion patients（ at the average age of 12.3 years） with mesially moved maxillary molar were treated by Distal-Jet appliance. Cephalometic radiographs and dental models were taken and analyzed before and after molar distalization. Results ： The treatment time was （4.3 ± 2.8 ） months. After treatment following effects were achieved：①The maxillary molar was distalized by （3.6 ± 0.75 ） mm per side with crown tilting distally by （ 3.5 ± 3 ） °. ②The first premolar was moved mesially by （2.1 ± 1.7） mm （ tilting movement）. Anterior overjet was increased by （ 1.47 ± 1.76） mm. ③In the vertical dimension,the maxillary molar was extruded slightly by （0.39 ±0.46） mm, the first premolar was extruded by （0.43 ±0.61 ） mm. ④The width between the central point of first maxillary molar was increased by （ 2.8 ± 1.1 ） mm. Conclusions ; The Distal-Jet appliance can distalize maxillary molars effectively. However,it may result in distaly tilting of molars and mesial movement of premolars.