应用CBCT评价隐形矫治技术远中移动上颌磨牙的临床疗效

CBCT evaluation of the clinic efficacy of Invisalign on upper molar distalization

目的通过锥形束计算机断层扫描(CBCT)三维测量评估隐形矫治技术远中移动上颌磨牙的疗效。方法收集应用Invisalign隐形矫治器作上颌磨牙远中移动的病例,共15例,平均年龄27岁8个月。使用微种植体或II类牵引增强前牙支抗,治疗前后分别拍摄CBCT。使用Sim Plant 11.04软件测量上颌磨牙三维方向移动量和切牙近远中向移动量,与预期牙移动量作比较,使用SPSS 19.0软件包进行统计分析。结果第一和第二磨牙预期远中移动量平均为(2.33±1.06)mm,实际移动量为(1.92±1.00)mm,表达率为82.4%。与预期移动量相比,上颌磨牙实际远中倾斜4.12°、颊向倾斜4.19°,第一磨牙压入0.99mm,第二磨牙压入1.88mm。磨牙三维方向的实际与预期移动量之间的差异均有统计学意义(P<0.01),而切牙的实际与预期近远中向位移无统计学差异(P>0.05)。结论 Invisalign隐形矫治技术能够有效地远中移动上颌磨牙,伴有压入和轻微的远中和颊向倾斜。远中移动上颌磨牙时,使用微种植支抗或II类牵引能够有效控制前牙支抗。

Objective To evaluate the efficacy of Invisalign on upper molar distalization via Cone-beam computed tomography（CBCT） 3-dimensional measurement. Methods Orthodontic patients subjected to upper molar distalization with Invisalign were enrolled in this study. Mini-implant or XII elastics were used to reinforce the anchorage during molar distalization. CBCT images were obtained before the treatment and after upper molars were fully distalized. The actual molar movements on 3 dimensions were quantified by Sim Plant 11.04 software and compared with the planned value. The anterior-posterior movement of incisors was also evaluated. SPSS 19.0 software was used for statistical analysis. Results 15 patients with mean age of 27 years and 8 months were included. There were significant differences between the actual and planned movement values for all the upper molars. The first and second upper molars moved distally 1.92±1.00 mm on average, with an efficacy of 82.4%（actual movement/planned movement in mesial-distal direction）. Compared to the planned movement, upper molars had an extra distal tipping of 4.12° and buccal inclination of 4.19°. The first molar had an extra intrusion of 0.99 mm, while the second molar showed a more significant intrusion of 1.88 mm. No significant proclination was observed in incisors compared to the planned movement. Conclusion Upper molar distalization could be effectively achieved by Invisalign appliances, with minor intrusion, distal tipping and buccal inclination. Miniimplants or CII elastics are sufficient to support the anchorage.