Initial Adhesion Behavior of Osteoblast on Titanium with Sub-Micron Scale Roughness

Abstract

The surface roughness of titanium could regulate various cellular functions such as survival and growth. In the context of cell adhesion to materials, cell spreading and cell shape are also closely linked to various cellular functions. Previously, we found that Ti substrate with a 100-nm scale surface roughness reduced cell survival. However, effects of surface roughness on cell shape were not investigated. Herein, we quantified the initial adhesion behavior of osteoblasts on a Ti substrate with ~100 nm scale surface roughness, which was prepared using silicon carbide (SiC) polishing paper. To evaluate the morphological parameters, such as perimeter, feret’s diameter, circularity, and spreading area on initial adhesion, cells were cultured on SiC-polished or mirror-polished Ti for 24 h. These morphological parameters were determined from fluorescence micrographs using image J software. Cells cultured on SiC-polished Ti exhibited poor spreading area. Additionally, pseudopodia formation and actin bundle construction of the cells were also poor on SiC-polished Ti, while the cells cultured on the mirror-polished Ti exhibited clear F-actin and greater overall cytoskeletal activity. On a Ti substrate, ~100 nm scale surface roughness could be expected to inhibit the cell spreading and pseudopodia formation of osteoblasts when compared to those cultured on a smooth substrate. Thus, consistent with our earlier reports, the surface roughness of the substrate is linked to reduced cellular functions such as cell growth and differentiation.