Department of Materials Science and Engineering, McMaster University, Hamilton, ON, Canada. Department of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Milan, Italy.
Nanotechnology. 2020 Mar 20;31(23):235101. doi: 10.1088/1361-6528/ab79ac. Epub 2020 Feb 25.
Modifications to the compositional, topographical and morphological aspects of bone implants can lead to improved osseointegration, thus increasing the success of bone implant procedures. This study investigates the creation of dual-scale topography on Ti-5Al-5Mo-5V-3Cr (Ti5553), an alloy not presently used in the biomedical field, and compares it to Ti-6Al-4V (Ti64), the most used Ti alloy for bone implants. Dual-scale surface topography was obtained by combining selective laser melting (SLM) and electrochemical anodization, which resulted in micro- and nanoscale surface features, respectively. Ti5553 and Ti64 samples were manufactured by SLM and showed comparable surface topography. Subsequent electrochemical anodization succeeded in forming titania nanotubes (TNTs) on both alloys, with larger nanotubes obtained with Ti5553 at all investigated anodization voltages. At an anodization voltage of 40 V, a minimum time of 20 min was necessary to have nanotube formation on the surface of either alloy, while only nanopores were evident for shorter times. Seeded Saos-2 cells showed ideal interactions with surface-modified structures, with filopodia extending to both surface microparticles characteristic of SLM and to the interior of TNTs. Attractiveness of Ti5553 lies in its lower elastic modulus (E = 72 GPa) compared to Ti64, which should mitigate stress-shielding phenomena in vivo. This, combined with the analogous results obtained in terms of dual-scale surface topography and cell-substrate interaction, could indicate Ti5553 as a promising alternative to the widely-employed Ti64 for bone implant device manufacturing.
对骨植入物的组成、形貌和形态方面进行修饰可以促进骨整合，从而提高骨植入物手术的成功率。本研究探索了在 Ti-5Al-5Mo-5V-3Cr（Ti5553）上制造双尺度形貌，Ti5553 是一种目前尚未用于生物医学领域的合金，并将其与最常用于骨植入物的 Ti-6Al-4V（Ti64）进行了比较。双尺度表面形貌是通过将选择性激光熔化（SLM）和电化学阳极氧化相结合而获得的，分别得到微纳尺度的表面特征。Ti5553 和 Ti64 样品通过 SLM 制造，表现出相似的表面形貌。随后的电化学阳极氧化成功地在两种合金上形成了二氧化钛纳米管（TNTs），在所有研究的阳极氧化电压下，Ti5553 获得的纳米管更大。在 40 V 的阳极氧化电压下，在合金表面形成纳米管需要最小 20 分钟的时间，而较短时间内只能看到纳米孔。接种 Saos-2 细胞与表面改性结构表现出理想的相互作用，丝状伪足延伸到 SLM 特征的表面微颗粒和 TNTs 的内部。Ti5553 的吸引力在于其与 Ti64 相比弹性模量较低（E=72 GPa），这应该可以减轻体内的应力屏蔽现象。这与双尺度表面形貌和细胞-基底相互作用方面获得的类似结果相结合，表明 Ti5553 可能是一种有前途的替代 Ti64 的选择，用于制造骨植入物设备。
