Department of Physics, Chemistry and Biology, Laboratory of Applied Physics, Linköping University, SE-581 83 Linköping, Sweden.
J Biomed Mater Res A. 2010 Aug;94(2):389-95. doi: 10.1002/jbm.a.32708.
A variety of surface modifications have been tested for the enhancement of screw fixation in bone, and locally delivered anti-osteoporosis drugs such as bisphosphonates (BP) are then of interest. In this in vivo study, the impact of surface immobilized BP was compared with systemic BP delivery and screws with no BP. After due in vitro characterization, differently treated stainless steel (SS) screws were divided into four groups with 10 rats each. Three of the groups received screws coated with sol-gel derived TiO(2) and calcium phosphate (SS+TiO(2)+CaP). One of these had no further treatment, one had alendronate (BP) adsorbed to calcium phosphate mineral, and one received systemic BP treatment. The fourth group received uncoated SS screws and no BP (control). The screw pullout force was measured after 4 weeks of implantation in rat tibiae. The immobilized amount and release rate of alendronate could be controlled by different immersion times. The SS+TiO(2)+CaP coating did not increase the pullout force compared to SS alone. Surface delivered alendronate enhanced the pullout force by 93% [p = 0.000; 95% Confidence Interval (CI): 67-118%] compared to SS, and by 39% (p = 0.044; 95% CI: 7-71%) compared to systemic alendronate delivery. Both surface immobilized and systemically delivered alendronate improved implant fixation. Also, locally delivered, that is, surface immobilized alendronate showed a better fixation than systemically delivered. Using sol-gel derived TiO(2) as a platform, it is possible to administer controllable amounts of a variety of BPs.
已经有多种表面改性方法被用于增强骨内螺钉固定，局部递送的抗骨质疏松药物如双膦酸盐（BP）因此受到关注。在这项体内研究中，比较了表面固定 BP 与全身 BP 递送以及无 BP 的螺钉的影响。在适当的体外特性分析后，用不同方法处理的不锈钢（SS）螺钉被分为 4 组，每组 10 只大鼠。其中 3 组的螺钉涂有溶胶-凝胶衍生的 TiO2 和磷酸钙（SS+TiO2+CaP）。其中一组没有进一步处理，一组将阿仑膦酸钠（BP）吸附到磷酸钙矿物上，还有一组接受全身 BP 治疗。第四组接受未涂层的 SS 螺钉且无 BP（对照）。在大鼠胫骨中植入 4 周后测量螺钉拔出力。通过不同的浸泡时间可以控制阿仑膦酸钠的固定量和释放率。与单独的 SS 相比，SS+TiO2+CaP 涂层并没有增加拔出力。与 SS 相比，表面递送的阿仑膦酸钠将拔出力提高了 93%[p = 0.000；95%置信区间（CI）：67-118%]，与全身阿仑膦酸钠递送相比提高了 39%（p = 0.044；95%CI：7-71%）。表面固定和全身递送的阿仑膦酸钠都改善了植入物固定。此外，局部递送，即表面固定的阿仑膦酸钠的固定效果优于全身递送。使用溶胶-凝胶衍生的 TiO2 作为平台，可以管理多种 BP 的可控剂量。
