Nanomodified plasma-sprayed titanium coatings have been shown in various studies to improve the early osseointegration of orthopedic implants, although little attention has been paid to the interactions that occur between coating surfaces and osteoblast cells. The aim of this study is to determine how surface structure influences cytoskeleton distribution and cellular differentiation and to assess the role of topography in regulating osteogenic fate. The results show that synergistic effects are achieved on hierarchically structured surfaces, with better cell spreading on nanotexture and multidimensional cytoskeleton distribution occurring over rough macroporous structure. Evidence of greater cytoskeleton reorganization and higher intracellular tension was also revealed.

A large variety of bioceramics have been successfully utilized as implant materials for promoting fixation of bony tissues. Different bioceramics exhibited markedly different proliferation rates of the osteoblast cells in vitro. Clarification of the mechanism about the attachment and proliferation/differentiation of the cells would contribute to selecting suitable biomaterials for hard tissue replacement. Nanostructured hydroxyapatite (HA) coatings have been produced and they have shown promising mechanical performances. The present study employed the 2-dimentional gel electrophoresis assay for comprehensively studying the proteomics of the cells proliferated on the nanostructured HA coating. Results showed that the nanostructured HA coatings promoted proliferation of the osteoblast cells. Alkaline phosphatase (ALP) assay revealed an increased ALP activity of the proliferated viable cells, and obviously the presence of the nanosized pores can enhance the anchoring and stretching of the cells. No obvious difference in the 2-D gel maps taken for the cells proliferated on the HA coating and for control can be found. This in turn suggests that the nanostructured HA coating induces minor changes in the cells. The promoted cell proliferation by the HA coating could then be possibly explained by the affected apoptosis/cell cycle of the cells.