Enhanced Dispersion of TiO2 Nanoparticles in a TiO2/PEDOT:PSS Hybrid Nanocomposite via Plasma-Liquid Interactions

A facile method to synthesize a TiO2/PEDOT:PSS hybrid nanocomposite material in aqueous solution through direct current (DC) plasma processing at atmospheric pressure and room temperature has been demonstrated. The dispersion of the TiO2 nanoparticles is enhanced and TiO2/polymer hybrid nanoparticles with a distinct core shell structure have been obtained. Increased electrical conductivity was observed for the plasma treated TiO2/PEDOT:PSS nanocomposite. The improvement in nanocomposite properties is due to the enhanced dispersion and stability in liquid polymer of microplasma treated TiO2 nanoparticles. Both plasma induced surface charge and nanoparticle surface termination with specific plasma chemical species are proposed to provide an enhanced barrier to nanoparticle agglomeration and promote nanoparticle-polymer binding

Quantitative in vitro comparison of the thrombogenicity of commercial dental implants

BACKGROUND Dental implants often have surface modifications that alter surface topography and chemistry to improve osseointegration and thereby increase treatment predictability. Surface contact-induced blood coagulation is associated with the onset of osseointegration. PURPOSE To quantitatively evaluate the thrombogenicity of two commercially available dental implants that have similar surface roughness but different surface chemistry. MATERIAL AND METHODS Two commercially available dental implants with anodized or sandblasted acid-etched surfaces were evaluated for thrombogenic properties. Thrombogenicity was assessed by incubating implants for 1 hour in fresh, partially heparinized blood followed by hemocyte quantification, microscopic evaluation, and quantification of thrombogenic biomarkers. RESULTS Fibrin coverage was significantly higher on the anodized surface compared with the sandblasted acid-etched surface (P < 0.0001). Platelet and white blood cell attachment followed a similar pattern. The increased thrombogenicity was confirmed based on a significant increase in the levels of the coagulation cascade biomarkers, thrombin antithrombin complex, and β-thromboglobulin (all P < 0.05). CONCLUSION Dental implants with comparable roughness but differing surface chemistry had differing extents of blood contact activation. These data suggest that surface chemistry from anodization augments implant thrombogenicity compared with that from sandblasting and acid-etching, which could have implications for osseointegration