Enhanced osteoblast functions on anodized titanium with nanotube-like structures

Previous studies have demonstrated increased osteoblast (bone-forming cells) adhesion on titanium and Ti-6Al-4V anodized to possess nanometer features compared with their unanodized counterparts. In this study, osteoblast long-term functions (specifically, synthesis of intracellular proteins, synthesis of intracellular collagen, alkaline phosphatase activity, and deposition of calcium-containing minerals) were determined on titanium anodized to possess either heterogeneous nanoparticles or ordered nanotubes. Titanium was anodized in dilute hydrofluoric acid at 20 V for 20 min to possess nanotubes, while titanium was anodized at 10 V for 20 min to possess nanoparticles. Most importantly, results showed that calcium deposition significantly increased on anodized titanium with nanotube-like structures compared with unanodized titanium and anodized titanium with nanoparticulate structures after 21 days of osteoblast culture. In this manner, the results of the present in vitro study indicated that anodization might be a promising quick and inexpensive method to modify the surface of titanium-based implants to induce better bone cell functions important for orthopedic applications. (c) 2007 Wiley Periodicals, Inc.