Former resident, Department of Orthodontics and Oral Facial Genetics, Indiana University School of Dentistry, Indiana University-Purdue University, Indianapolis, Ind.
Associate professor, Department of Restorative Dentistry, Division of Dental Biomaterials, Indiana University School of Dentistry, Indiana University-Purdue University, Indianapolis, Ind.
Am J Orthod Dentofacial Orthop. 2014 Apr;145(4):496-504. doi: 10.1016/j.ajodo.2013.12.022.
The detailed mechanical and histologic properties of stainless steel miniscrew implants used for temporary orthodontic anchorage have not been assessed. Thus, the purpose of this study was to compare them with identically sized titanium alloy miniscrew implants.
Forty-eight stainless steel and 48 titanium alloy miniscrew implants were inserted into the tibias of 12 rabbits. Insertion torque and primary stability were recorded. One hundred grams of tensile force was applied between half of the implants in each group, resulting in 4 subgroups of 24 specimens each. Fluorochrome labeling was administered at weeks 4 and 5. When the rabbits were euthanized at 6 weeks, stability and removal torque were measured in half (ie, 12 specimens) of each of the 4 subgroups. Microdamage burden and bone-to-implant contact ratio were quantified in the other 12 specimens in each subgroup. Mixed model analysis of variance was used for statistical analysis.
All implants were stable at insertion and after 6 weeks. The only significant difference was the higher (9%) insertion torque for stainless steel. No significant differences were found between stainless steel and titanium alloy miniscrew implants in microdamage burden and bone-to-implant contact regardless of loading status.
Stainless steel and titanium alloy miniscrew implants provide the same mechanical stability and similar histologic responses, suggesting that both are suitable for immediate orthodontic clinical loads.
用于临时正畸锚固的不锈钢微型植入物的详细机械和组织学特性尚未得到评估。因此，本研究的目的是将其与相同尺寸的钛合金微型植入物进行比较。
将 48 个不锈钢和 48 个钛合金微型植入物植入 12 只兔子的胫骨中。记录植入扭矩和初始稳定性。在每组的一半植入物之间施加 100 克的拉力，产生 4 个每组 24 个样本的亚组。在第 4 和第 5 周进行荧光标记。当兔子在 6 周时被安乐死时，在每组的一半（即 12 个样本）中测量稳定性和去除扭矩。在每个亚组的其余 12 个样本中量化微损伤负担和骨-植入物接触比。使用混合模型方差分析进行统计分析。
所有植入物在插入时和 6 周后均稳定。唯一的显著差异是不锈钢的插入扭矩高（9%）。无论加载状态如何，不锈钢和钛合金微型植入物的微损伤负担和骨-植入物接触比均无显著差异。
不锈钢和钛合金微型植入物提供相同的机械稳定性和相似的组织学反应，表明两者均适合立即进行正畸临床负荷。
