Abstract
The objective of this preliminary in vitro biological study was to assess the effect of the surface physicochemical and topographical properties of a novel bioactive titanium (BSP) obtained by BioSpark™ treatment. A short-term study was performed to evaluate the bone cell response to BSP and compare it to two commercially available materials: no treated (TI) and chemically etched (ETC) titanium. Material characterization was carried out using scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS), non-contact laser profilometry (LPM), and Thin Film X-ray Diffraction (TF-XRD). Surface analysis showed ETC to have the highest rough surface, followed by TI surface and then BSP being the smoothest material at micro level, but showing a sub micrometer porous structure covered with a “net-like” rough structure. The BSP surface was found to consist of a layer of amorphous calcium and phosphorus and crystalline titanium oxide, not detected in the other materials tested. Indirect biological cytotoxicity studies were performed to determine cell viability following incubation with the eluted extract of the materials. Results indicated no remarkable deterioration in cell viability. In particular, no detectable effect was observed on cellular viability as a result of the chemical interaction between the BSP bioactive surface and the surrounding culture medium. Direct cellular studies showed that the material surface resulted in good cell adhesion on BSP samples. This could be related to both the nano-roughness, and also the crystallinity of the superficial layer of titanium oxide coupled with bioactive Ca- and P-chemical enrichment. The cellular proliferation analysis demonstrated a remarkably higher activity for the cells cultured on BSP, with values significantly higher than the other test materials and the control for all time points. These findings are highly suggestive that the surface properties of the BioSpark™ treated titanium significantly increases cell proliferation rate. In conclusion, this study has demonstrated that the novel bioactive treatment shows potential as a method for improving osteointegration properties of titanium for orthopaedic and dental implants. (Journal of Applied Biomaterials & Biomechanics 2004; 2: 35–44)