Iwai Hiroaki, Motoyoshi Mitsuru, Uchida Yasuki, Matsuoka Miho, Shimizu Noriyoshi
Postgraduate student, Department of Orthodontics, School of Dentistry, Nihon University, Tokyo, Japan.
Associate professor, Department of Orthodontics, Division of Clinical Research, Dental Research Center, School of Dentistry, Nihon University, Tokyo, Japan.
Am J Orthod Dentofacial Orthop. 2015 Apr;147(4):483-91. doi: 10.1016/j.ajodo.2014.12.017.
We evaluated the effects of screw placement angle on the frequency of root contact and the effects of root contact on screw stability, comparing self-drilling and self-tapping methods.
In total, 80 patients with 142 screws (diameter, 1.6 mm; length, 8.0 mm) were included. Cone-beam computed tomography images were taken. Cortical bone thickness, interroot distance, shortest distance between the screw and adjacent tooth root, and screw placement angle were measured.
The success rates of the screws were 91.5% for the self-drilling method and 94.4% for the self-tapping method (P >0.05). The self-drilling screws tended to contact the distal tooth roots in the right maxilla. In the self-drilling method, the failure rate was significantly higher in the root contact group than in the no-contact group (P <0.05).
The success rate was not significantly different between the self-drilling and the self-tapping methods in the maxilla. Avoidance of tooth root contact may improve the success rate more in the self-drilling method than in the self-tapping method.
我们比较了自攻钻法和自攻丝法，评估了螺钉置入角度对牙根接触频率的影响以及牙根接触对螺钉稳定性的影响。
共纳入80例患者，置入142枚螺钉（直径1.6毫米；长度8.0毫米）。拍摄锥形束计算机断层扫描图像。测量皮质骨厚度、牙根间距、螺钉与相邻牙根之间的最短距离以及螺钉置入角度。
自攻钻法螺钉成功率为91.5%，自攻丝法为94.4%（P>0.05）。自攻钻螺钉倾向于接触右上颌的远中牙根。在自攻钻法中，牙根接触组的失败率显著高于无接触组（P<0.05）。
上颌自攻钻法和自攻丝法的成功率无显著差异。与自攻丝法相比，避免牙根接触在自攻钻法中可能更有助于提高成功率。
