Cell Responses to Nanostructured Zirconium Oxide Coated Titanium

ZrO₂ coated surface’s nano-pyramidal structures and the surface charges are expected to provide strong binding of protein to the material surface and further cell proliferation. This advanced surface technology is not applied to dental implant surface yet. Objective:  To evaluate nano-scale ZrO₂ surface modification enhances initial cell adhesion and growth. Method :  Machined cp titanium plate (McMaster-Carr) was coated with nanocrystalline ZrO₂ films by ion beam assisted deposition method at the Nanotechnology Laboratory of UNMC (Zr). Machined cp titanium plate without surface treatment was prepared as a control group (M). Surface chemistry and topography of samples were characterized with SEM & EDX prior to cell culture. Materials (n=6) were placed in cell media and osteoblasts (MC3T3-E1), OMA-AD (C57Bl/6 mouse stromal cell), and fibroblasts (3T3) of 10,000 cells/cm³ were inoculated onto metal surfaces. Cell attachment, proliferation and morphology were evaluated with fluorescence microscope (Zeiss) at 2, 4, 8, 12, 24, 48, & 72 hours with DAPI and Actin stains (Sigma-Aldrich). Results: SEM demonstrated Zr was smoother surface than M and EDX indicated all samples contained titanium with small amounts of carbon. Cells were well spread on all surfaces. Cell morphology on smooth surfaces appeared more compact. Cell numbers were greater for Zr than M at all time intervals except at initial 2 hour point. Conclusion: Cells attached, spread and proliferated in similar fashion on both groups. The smooth nanoengineered ZrO₂ coating showed increased number of healthy looking cells compared to rougher machined surface.