Construction and Biological Performance of Surface Treated Porous Titanium Scaffold Using Nanotube Arrays of Anatase

Abstract

TiO2 nanotube in diameter of ~ 100 nm array films were prepared on a porous titanium scaffold with a porosity of 70% via anodic oxidation. The morphology and phases of the films were characterized, and the thermal stability of the films were also studied. In-vitro, the bioactivity of the modified scaffolds was evaluated by simulated body fluid immersion test. In vivo, the scaffolds were implanted into the back muscles of the dog for 6 months. Results show that the anatase nanotubues give better bioactivity than the amorphous. The scaffold after anodic oxidation and annealing at 500 °C for 5 hours not only can induce the formation of hydroxyapatite, but also can induce blood vessel formation and promote the expressions of bone morphogenetic protein BMP-2. The BMP-2 concentrations is 5.57±0.20 μ/L for the scaffold been anodically oxidated and heat-preserved, the value is much higher than that of untreated scaffold(2.78±0.16 μg/L)or only been anodically oxidated(2.86±0.17 μg/L). It shows that the anatase TiO2 nanotubes can contribute to the potential osteoinductivity. This study will promote the development of novel functional porous supports.