Bone-like apatite growth on controllable macroporous titanium scaffolds coated with microporous titania

In this study, a simple, cost-effective approach of polymeric foam replication was used to produce three-dimensionally macroporous titanium scaffolds with controllable porosities and mechanical properties. Two kinds of porous titanium scaffolds with different porosities (74.7% and 87.6%) and pore sizes (360 µm and 750 µm) were fabricated. Both of the scaffolds exhibit good compressive strength (24.5 MPa and 13.5 MPa) with a low elastic modulus (0.23 GPa and 0.11 GPa), approximating the mechanical properties of nature human cancellous bone (E = 10-50 MPa, σ = 0.01-3.0 GPa). Thereafter, the scaffolds were surface modified using plasma electrolyte oxidation (PEO) process to gain a bioactive porous titania ceramic coating. The SBF immersion test indicates PEO treated scaffolds show excellent bioactivity as the apatite rapidly nucleates and grows on the scaffold surface during 3-28 days. The results suggest that the highly porous titanium scaffolds with titania bioactive coatings are promising in cancellous bone replacement.