Department of Orthodontics, Showa University School of Dentistry, 2-1-2 Kitasenzoku, Ohta-ku, Tokyo 145-8515, Japan.
J Mech Behav Biomed Mater. 2012 Sep;13:230-6. doi: 10.1016/j.jmbbm.2012.01.016. Epub 2012 Jan 31.
Cells adhering onto implant surfaces are subjected to oxidative stress during wound healing processes. Although titanium and its alloys are among the most frequently used biomaterials in orthopedic and dental implants, titanium surfaces do not have antioxidant properties, and cells grown on these surfaces can show permanent oxidative stress. The present study assessed the antioxidant property and osteogenic properties of titanium samples with or without oxidation treatments. A thick rutile TiO₂ film was observed on thermally oxidized titanium surfaces, while amorphous anatase TiO₂ formed on anodically oxidized titanium surfaces prepared by discharging in 1 M Na₂HPO₄. A resistance to the depletion of reduced glutathione in adherent osteoblasts, which correlates with antioxidant behavior, occurred on anodically oxidized titanium. Enhanced osteogenic gene expressions and nano-biomechanical properties of mineralized tissue were achieved on anodically oxidized titanium, in comparison with thermally oxidized or untreated titanium. Thus, anodic oxidation by discharging in electrolyte is expected to be a useful surface modification for titanium implants.
在伤口愈合过程中，黏附在植入物表面的细胞会受到氧化应激。尽管钛及其合金是骨科和牙科植入物中最常使用的生物材料之一，但钛表面没有抗氧化特性，在这些表面生长的细胞可能会表现出永久性的氧化应激。本研究评估了具有或没有氧化处理的钛样品的抗氧化特性和成骨特性。在热氧化的钛表面上观察到厚的锐钛矿 TiO₂ 薄膜，而在通过在 1 M Na₂HPO₄ 中放电制备的阳极氧化的钛表面上形成非晶态锐钛矿 TiO₂。在阳极氧化的钛上，黏附的成骨细胞中还原型谷胱甘肽的消耗减少，这与抗氧化行为相关。与热氧化或未处理的钛相比，阳极氧化的钛上实现了增强的成骨基因表达和矿化组织的纳米生物力学特性。因此，通过在电解质中放电进行阳极氧化有望成为钛植入物的有用表面改性方法。
