Angle Orthod. 2021 Jul 1;91(4):509-514. doi: 10.2319/083020-756.1.
To date, the clinical stability of dual-thread orthodontic miniscrews has not been studied. This study aimed to compare the primary stability and long-term clinical success rate of dual-thread and cylindrical orthodontic miniscrews and to examine the association between various clinical factors and the success rate of miniscrews.
A total of 145 cylindrical and 135 dual-thread miniscrews were inserted in the maxillary and mandibular buccal alveolar areas of 142 patients. The torque and Periotest (Siemens, Bensheim, Germany) values were recorded during insertion and removal. The effect of clinical variables such as sex, age, screw design, jaw, side of placement, root proximity, and site of placement on the success rate was examined using logistic regression analysis.
There was no statistically significant difference (P = .595) in the overall clinical success rate between the two designs, with an overall success rate of 82.1% and 84.4% for the cylindrical and dual-thread miniscrews, respectively. Age and screw-root proximity were significantly associated with failure (P < .05).
The dual-thread miniscrews did not show superior long-term stability and clinical success rate as compared with the cylindrical miniscrews. The results of this study suggest that patient age and screw-root proximity influence the clinical success rate of miniscrews.
迄今为止，双螺纹正畸微螺钉的临床稳定性尚未得到研究。本研究旨在比较双螺纹和圆柱状正畸微螺钉的初始稳定性和长期临床成功率，并研究各种临床因素与微螺钉成功率之间的关系。
将 145 枚圆柱状和 135 枚双螺纹微螺钉分别植入 142 名患者的上颌和下颌颊侧牙槽骨中。在插入和取出时记录扭矩和 Periotest（德国西门子公司，本海姆）值。使用逻辑回归分析，研究性别、年龄、螺钉设计、颌骨、植入部位侧别、临近牙根和植入部位等临床变量对成功率的影响。
两种设计的总体临床成功率无统计学差异（P=.595），圆柱状和双螺纹微螺钉的总体成功率分别为 82.1%和 84.4%。年龄和螺钉与牙根的接近程度与失败显著相关（P<.05）。
与圆柱状微螺钉相比，双螺纹微螺钉并未显示出更高的长期稳定性和临床成功率。本研究结果表明，患者年龄和螺钉与牙根的接近程度影响微螺钉的临床成功率。
