Titanium oxide nanotubes with controlled morphology for enhanced bone growth

An array of vertically aligned titanium oxide nanotubes was grown on the surface of titanium substrate by anodization. A chemical treatment with NaOH solution to make them more bioactive with a formation of nanoscale sodium titanate structure. The presence of such treated TiO2 nanotubes significantly accelerated the kinetics of hydroxyapatite growth by a factor of as much as 7. The adhesion/growth of osteoblast cells is also significantly accelerated by the topography of the TiO2 nanotubes with the filopodia of the growing cells actually going into the nanotube pores, producing a locked-in cell structure. The number of the adhered cells on the TiO2 nanotubes increases by as much ∼400% as compared to the Ti metal, most likely caused by the pronounced topological feature, significantly increased surface area, as well as the in-between-nanotube pathways for fluid. Such an array of TiO2 nanotubes well adherent on Ti implant surface can be useful for accelerated bone growth in orthopaedic/dental applications.