Enhanced Osteoblast Differentiation on Scaffolds Coated with TiO2 Compared to SiO2 and CaP Coatings

The aim was to compare the protein release from normal human osteoblasts (NHO) cultured on scaffolds with similar morphology but different coatings. Different ceramic coatings; TiO2, SiO2 and calcium phosphate (CaP); Ca9HPO4(PO4)5OH, were applied to porous TiO2 scaffolds prepared by polymer sponge replication. NHO were cultured on scaffolds in triplicates. The concentration of cytokines and Ca2+, and alkaline phosphatase (ALP) activity in the cell media was quantified. The secretion of osteopontin, osteoprotegerin, vascular endothelial growth factor and interleukin-6 was higher from NHO on TiO2 compared to SiO2 and CaP. The secretion from cells on the three scaffolds was, however, either similar or lower than the control cells cultured on plastic. The Ca2+ concentration was higher in cell media on CaP the first week, and no difference in ALP activity was observed. TiO2 coating induced a higher secretion of factors indicating enhanced osteoblast differentiation as compared to CaP and SiO2.