WM Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164-2920, USA.
Acta Biomater. 2010 Aug;6(8):3349-59. doi: 10.1016/j.actbio.2010.01.046. Epub 2010 Feb 2.
The relatively high cost of manufacturing and the inability to produce modular implants have limited the acceptance of tantalum, in spite of its excellent in vitro and in vivo biocompatibility. In this article, we report how to process Ta to create net-shape porous structures with varying porosity using Laser Engineered Net Shaping (LENS) for the first time. Porous Ta samples with relative densities between 45% and 73% have been successfully fabricated and characterized for their mechanical properties. In vitro cell materials interactions, using a human fetal osteoblast cell line, have been assessed on these porous Ta structures and compared with porous Ti control samples. The results show that the Young's modulus of porous Ta can be tailored between 1.5 and 20 GPa by changing the pore volume fraction between 27% and 55%. In vitro biocompatibility in terms of MTT assay and immunochemistry study showed excellent cellular adherence, growth and differentiation with abundant extracellular matrix formation on porous Ta structures compared to porous Ti control. These results indicate that porous Ta structures can promote enhanced/early biological fixation. The enhanced in vitro cell-material interactions on the porous Ta surface are attributed to its chemistry, its high wettability and its greater surface energy relative to porous Ti. Our results show that these laser-processed porous Ta structures can find numerous applications, particularly among older patients, for metallic implants because of their excellent bioactivity.
尽管钽具有优异的体外和体内生物相容性，但由于其制造成本相对较高且无法生产模块化植入物，因此限制了其应用。本文首次报道了如何使用激光工程净成形（LENS）加工 Ta 以创建具有不同孔隙率的净成形多孔结构。已经成功制造了相对密度在 45%至 73%之间的多孔 Ta 样品，并对其机械性能进行了表征。在这些多孔 Ta 结构上评估了使用人胎成骨细胞系的体外细胞材料相互作用，并与多孔 Ti 对照样品进行了比较。结果表明，通过改变孔隙率在 27%至 55%之间，可以将多孔 Ta 的杨氏模量调整在 1.5 至 20 GPa 之间。在体外生物相容性方面，通过 MTT 测定和免疫化学研究表明，与多孔 Ti 对照相比，多孔 Ta 结构上具有丰富的细胞外基质形成，具有出色的细胞黏附性、生长和分化。与多孔 Ti 相比，这些结果表明多孔 Ta 结构可以促进增强/早期生物固定。多孔 Ta 表面增强的体外细胞-材料相互作用归因于其化学性质、高润湿性和比多孔 Ti 更高的表面能。我们的研究结果表明，由于其出色的生物活性，这些激光加工的多孔 Ta 结构可以在许多金属植入物应用中找到，尤其是在老年患者中。
