Sydney Dental School, The University of Sydney, Sydney, Australia.
Department of Orthodontics, Sydney Dental Hospital, Sydney Local Health District, The University of Sydney, Sydney, Australia.
Eur J Orthod. 2019 Aug 8;41(4):360-369. doi: 10.1093/ejo/cjy059.
The aim of this study was to assess the potential of improving orthodontic miniscrews' (MSs) primary stability in vivo by evaluating the dispersion capacity of an injectable bone graft substitute (iBGS) through a newly designed hollow MS [The Sydney Mini Screw (SMS)] and its integration with the cortical and trabecular bone by using the femur and tibia in a New Zealand rabbit animal model.
In total, 24 MSs were randomly placed in each proximal tibia and femur of 6 New Zealand rabbits with an open surgery process. Aarhus MSs were used as controls and the effect of injection of iBGS was studied by implanting SMSs with and without iBGS injection. The dispersion of iBGS and the integration of the SMS were studied by using micro Computed Tomography (μCT) and histochemical analysis at two time points, 0 day and 8 weeks post-implantation.
iBGS was successfully injected through the SMS and hardened in situ. After 8 weeks, μCT results revealed that the iBGS particles were resorbed and bone tissue was formed around the SMS and within its lateral exit holes.
This pilot animal study showed the high potential of the combined use of iBGS and SMS as a newly developed technique to promote the primary stability of MSs.
本研究旨在通过评估可注射骨替代物（iBGS）的分散能力，评估新型空心微螺钉（SMS）[悉尼微型螺钉（SMS）]及其与皮质骨和松质骨整合的潜力，从而提高体内正畸微螺钉（MSs）的初始稳定性。使用新西兰兔动物模型的股骨和胫骨。
总共将 24 个 MS 随机放置在 6 只新西兰兔的每根胫骨和股骨近端，采用开放式手术过程。 Aarhus MSs 作为对照，通过植入带有和不带有 iBGS 注射的 SMS 来研究 iBGS 注射的效果。在植入后 0 天和 8 周，通过微计算机断层扫描（μCT）和组织化学分析研究 iBGS 的分散和 SMS 的整合。
iBGS 可通过 SMS 成功注射并原位硬化。8 周后，μCT 结果显示 iBGS 颗粒被吸收，SMS 周围和侧出口孔内形成了骨组织。
这项初步的动物研究表明，iBGS 和 SMS 的联合使用具有很大的潜力，可作为一种新技术促进 MSs 的初始稳定性。
