W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University , Pullman, Washington 99164-2920, United States.
Veterinary Teaching Hospital, Washington State University , Pullman, Washington 99164, United States.
ACS Appl Mater Interfaces. 2017 Aug 9;9(31):25731-25737. doi: 10.1021/acsami.7b05574. Epub 2017 Jul 28.
Plasma-sprayed hydroxyapatite (HA)-coated titanium implants have been widely used in orthopedic applications due to their inheritance of an excellent mechanical property from titanium and great osteoconductivity from HA. However, the lack of osteoinductivity limits their further applications. In this study, 1 wt % MgO and 0.5 wt % SiO were mixed with HA for making plasma-sprayed coatings on titanium implants. Plasma-sprayed HA- and MgO/SiO-HA-coated titanium implants showed adhesive bond strengths of 25.73 ± 1.92 and 23.44 ± 2.89 MPa, respectively. The presence of MgO and SiO significantly increased the osteogenesis, osseointegration, and bone mineralization of HA-coated titanium implants by the evaluation of their histomorphology after 6, 10, and 14 weeks of implantation in rat distal femoral defects. Implant pushout tests also showed a shear modulus of 149.83 ± 3.69 MPa for MgO/SiO-HA-coated implants after 14 weeks of implantation, compared to 52.68 ± 10.41 MPa for uncoated implants and 83.92 ± 3.68 MPa for pure HA-coated implants; These are differences in the shear modulus of 96% and 56.4%, respectively. This study assesses for the first time the quality of the bone-implant interface of induction plasma-sprayed MgO and SiO binary-doped HA coatings on load-bearing implants compared to bare titanium and pure HA coatings in a quantitative manner. Relating the osseointegration and interface shear modulus to the quality of implant fixation is critical to the advancement and implementation of HA-coated orthopedic implants.
等离子喷涂羟基磷灰石（HA）涂层钛植入物由于其继承了钛的优异机械性能和 HA 的良好骨传导性，已广泛应用于骨科领域。然而，其缺乏成骨诱导性限制了其进一步的应用。在这项研究中，将 1wt%的 MgO 和 0.5wt%的 SiO 与 HA 混合，用于在钛植入物上制备等离子喷涂涂层。等离子喷涂的 HA 和 MgO/SiO-HA 涂层钛植入物的黏附强度分别为 25.73±1.92MPa 和 23.44±2.89MPa。MgO 和 SiO 的存在通过对大鼠股骨远端缺损植入后 6、10 和 14 周的组织形态学评估，显著促进了 HA 涂层钛植入物的成骨、骨整合和骨矿化。植入物推出试验还显示，在植入 14 周后，MgO/SiO-HA 涂层植入物的剪切模量为 149.83±3.69MPa，而未涂层植入物为 52.68±10.41MPa，纯 HA 涂层植入物为 83.92±3.68MPa；这分别是剪切模量差异的 96%和 56.4%。本研究首次定量评估了在承载植入物上诱导等离子喷涂的 MgO 和 SiO 二元掺杂 HA 涂层与裸钛和纯 HA 涂层相比，对骨-植入物界面质量的影响。将骨整合和界面剪切模量与植入物固定的质量联系起来，对于促进和实施 HA 涂层骨科植入物至关重要。
