Titania Nanotubes: Novel Nanostructures for Improved Osseointegration

Nanostructured one dimensional titanium oxides such as nanotubes and nanowires have raised interest lately due to their unique electronic and optical properties. These materials also have shown significant potential as biomaterials because of their ability to modulate protein and cellular interactions. In this review, synthesis and modification of titania nanotubes have been discussed with emphasis on electrochemical synthesis and wet chemical synthesis and their heat treatment of resulting titania nanotubes. The biomedical applications of titania nanotubes were subsequently discussed in detail with a focus on osseointegration. The areas discussed are cell responses to titania nanotubes, effects of titania nanotubes on stem cell proliferation and differentiation, titania nanotubes as drug delivery vehicles, surface modification of titania nanotubes, and in vivo studies using titania nanotubes. It is concluded that the in vitro and in vivo study clearly demonstrates the efficacy of titania nanotube in enhancing osseointegration of orthopedic implants and much of the future work is expected to focus on improving implant functions by modulating the physical and chemical properties of the nanotubes and by locally delivering bioactive molecules in a sustained manner.