Texture direction of combined microgrooves and submicroscale topographies of titanium substrata influence adhesion, proliferation, and differentiation in human primary cells

Objective: This study aimed to identify the optimal micro- and submicroscale topographies of titanium (Ti) substrata that would most significantly influence adhesion, proliferation, and other activities of these cells. Design: Truncated V-shaped microgrooves in 60 μm-wide and 10 μm-deep cross-sections with 0°, 30°, 60°, or 90°angles between the microgrooves and ridge-top submicroscale texture were created on the Ti substrata (designated NE60/10-0°, NE60/10-30°, NE60/10-60°and NE60/10-90°, respectively). Ground titanium with submicroscale texture but with no microgrooves was used as the control substratum, NE0. Scanning electron microscopic observation and the assays determining the cell adhesion, cell proliferation and osteoblast differentiation were performed. Results: Cells more actively migrated into the microgrooves on NE60/10-30°than into the microgrooves on any other substrata tested, suggesting that the cells utilise the increased surface area of the substrata at the microscale level. NE60/10-0°and NE60/10-30°substrata generally enhanced adhesion, proliferation, alkaline phosphatase activity, and osteoblast differentiation of human primary cells when compared to other Ti substrata, and significant correlations were observed between these cellular activities. Conclusions: Here, we show that the contact guidance of human primary cells grown on Ti substrata can be controlled more by specific submicroscale textures on ridge tops than by the dimensions of surface microgrooves only. Also, the degree of angles created between the submicroscale textures and microgrooves on Ti substrata significantly affect cell adhesion, proliferation and differentiation in human primary cells.