Gao Y, Hu J, Guan T H, Wu J, Zhang C B, Gao B
School of Stomatology, Fourth Military Medical University, 145 West Changle Road, 710032, Xi'an, People's Republic of China.
Lasers Med Sci. 2014 Jan;29(1):9-17. doi: 10.1007/s10103-012-1226-9. Epub 2012 Nov 9.
In order to improve the surface bioactivity of titanium implants, CaCO₃ and CaHPO₄·2H₂O powder was used to fabricate a calcium phosphate (CaP) coating using laser rapid forming (LRF) technology. The surface characterization showed that a porous and beta-tricalcium phosphate (beta-TCP) layer with small amount of alpha-TCP was formed on commercial pure titanium (Ti). The bonding strength between the coating and the Ti substrate was above 40.17 MPa measured by the means of pull-off test. The elastic modulus and the average microhardness of the coating were 117.61 GPa and 431.2 HV₀.₁, respectively. Through the static immersion test, it was proved that the coating could not only prevent the corrosion of Ti but also promote the redeposition of beta-TCP in artificial saliva. Osteoblasts possessed good attachment performance and strong proliferation ability on the surface of LRF coating (p < 0.05) in our cell experiments. This result demonstrated that the LRF coating could improve the surface cytocompatibility of titanium. Using scanning electron microscopy observation, it was found that osteoblasts grown on LRF coating formed multiple layers in pours. The result of reverse transcription PCR analysis demonstrated that the expressions of ITGβ1 and BMP-2 were significantly (p < 0.05) upregulated on the LRF coating in a time-dependent manner, compared with uncoated Ti. These findings suggested that the LRF technology might be a promising potential treatment for fabricating CaP coatings on titanium implants.
为了提高钛植入物的表面生物活性，采用激光快速成型（LRF）技术，使用碳酸钙（CaCO₃）和磷酸氢钙二水合物（CaHPO₄·2H₂O）粉末制备了磷酸钙（CaP）涂层。表面表征显示，在商业纯钛（Ti）上形成了含有少量α-磷酸三钙的多孔β-磷酸三钙（β-TCP）层。通过拉伸试验测得涂层与Ti基体之间的结合强度高于40.17MPa。涂层的弹性模量和平均显微硬度分别为117.61GPa和431.2HV₀.₁。通过静态浸泡试验证明，该涂层不仅可以防止Ti的腐蚀，还可以促进β-TCP在人工唾液中的再沉积。在我们的细胞实验中，成骨细胞在LRF涂层表面具有良好的附着性能和较强的增殖能力（p<0.05）。该结果表明，LRF涂层可以提高钛的表面细胞相容性。通过扫描电子显微镜观察发现，在LRF涂层上生长的成骨细胞在孔隙中形成多层结构。逆转录聚合酶链反应分析结果表明，与未涂层的Ti相比，LRF涂层上ITGβ1和BMP-2的表达随时间显著上调（p<0.05）。这些发现表明，LRF技术可能是一种在钛植入物上制备CaP涂层的有前途的潜在方法。
