真空和大气等离子喷涂镁黄长石生物活性涂层的对比研究

A Comparative Study on Vacuum and Air Plasma Sprayed Bioactive Akermanite Coating

大气喷涂法制备的镁黄长石涂层是一种具有优良生物活性的新型骨科移植体涂层材料,但其结晶度较低,影响涂层的化学稳定性。本研究采用真空等离子喷涂法在钛合金表面制备了高结晶度的镁黄长石涂层。与大气喷涂镁黄长石涂层相比,真空喷涂镁黄长石涂层具有更高的磷灰石矿化能力,在SBF中浸泡6 d后表面即沉积了一层类骨磷灰石层,浸泡14 d后表面沉积的磷灰石层的厚度约为大气涂层的4倍。真空喷涂镁黄长石涂层的离子释放明显低于大气涂层,显示出更高的化学稳定性。骨髓间充质干细胞在真空和大气喷涂镁黄长石涂层表面粘附和铺展良好,在两种涂层表面的增殖速度均明显高于HA涂层。本研究表明真空等离子喷涂的镁黄长石陶瓷涂层因其显著提高的生物活性及化学稳定性,可能更适合用作人工关节涂层材料。

Air plasma-sprayed akermanite coating is a new type orthopedic implant coating material with high bonding strength and excellent bioactivity. However, its crystallinity is low which affects its chemical stability. In this study, high crystallinity akermanite coating has been prepared using vacuum plasma spray （VPS） method. VPS akermanite coating possesses improved apatite mineralization ability compared with APS coating. An apatite layer has formed on VPS akermanite coating surface after 6 d of immersion into simulated body fluid （SBF）, and the thickness of apatite layer on VPS coating is 4 times thicker than that on APS akermanite coating. The ionic release of VPS coating is significantly lower than that of APS coating, showing improved chemical stability. Furthermore, bone marrow stem cells （BMSCs） adhere to and spread well on the surface of both VPS and APS akermanite coat- ing surface without significant difference. The proliferation rate of BMSCs is significantly higher on VPS and APS akermanite coating surface than on HA coating. Our results suggest that vacuum plasma sprayed （VPS） akermanite coating is more suitable as orthopedic implant material due to its improved bioactivity and chemical stability.