* Graduate Dentistry Program, Orthodontics, Pontifical Catholic University of Paraná.
Eur J Orthod. 2013 Dec;35(6):766-71. doi: 10.1093/ejo/cjs095. Epub 2013 Feb 4.
This study aimed to evaluate biomechanical behaviour of inclined orthodontic mini-implants by analyzing its insertion torque (IT), axial pull-out strength (APS), and cortical bone thickness in contact with mini-implant (CBTC). A total of 102 mini-implants were inserted at 90 degree, 60 degree, and 45 degree to the surface of synthetic bone. Peak IT was measured, and the mini-implants were aligned with the mechanical testing machine to record the APS. The cortical bone thickness in contact with each mini-implant was measured after the pull-out test and the data were subjected to statistical analyses. The 45 degree group had a significantly higher IT compared with the 90 degree group (P < 0.05). There was a statistically significant increase in the average of cortical bone thickness in CBTC across the three groups (P < 0.05). A negative correlation between the angulation and the CBTC (r = -0.95, P < 0.05) and a positive correlation between the APS and the CBTC were observed (r = 0.34, P < 0.05). Mini-implants that are inserted more inclined to the surface of the bone provide greater IT and an increased contact with the cortical bone. The greater the CBTC, the greater is the APS.
本研究旨在通过分析倾斜角度对正畸微种植体的生物力学行为的影响，包括其植入扭矩（IT）、轴向抗拔出强度（APS）和与微种植体接触的皮质骨厚度（CBTC）。共将 102 个微种植体以 90 度、60 度和 45 度的角度植入合成骨表面。测量峰值 IT，然后将微种植体与机械试验机对齐，记录 APS。在拔出试验后测量每个微种植体接触的皮质骨厚度，并对数据进行统计分析。与 90 度组相比，45 度组的 IT 显著更高（P < 0.05）。三组之间 CBTC 的皮质骨厚度平均值呈显著增加趋势（P < 0.05）。角度与 CBTC 之间呈负相关（r = -0.95，P < 0.05），APS 与 CBTC 之间呈正相关（r = 0.34，P < 0.05）。更倾斜地植入骨表面的微种植体提供更大的 IT 和与皮质骨的更大接触。CBTC 越大，APS 越大。
