Agradecimentos:The authors would like to thank the State of Sao Paulo Research Foundation (FAPESP) (grant numbers 2013/26145-5 and 2013/08451-1), The Brazilian National Council for Scientific and Technological Development (CNPq) (grant numbers 442786/2014-0 and 304908/2015-0) and Fundo de Apoio ao Ensino, à Pesquisa e Extensão da UNICAMP (FAEPEX) (grant number 2032/15) for the financial support. The authors also express gratitude to Rafael Parra for his contribution and support in the Plasma Technology Lab at Univ Estadual Paulista (UNESP) and Elton José de Souza from the Department of Physics and Chemistry at UNESP for the AFM facility. Ver menos

Abstract: In this study, titanium (Ti) was modified with biofunctional and novel surface by micro-arc oxidation (MAO) and glow discharge plasma (GDP) and we tested the development of a three-species periodontopatogenic biofilm onto the treated commercially-pure titanium (cpTi) surfaces. Machined and sandblasted surfaces were used as control group. Several techniques for surface characterizations and monoculture on bone tissue cells were performed. A multispecies biofilm composed of Streptococcus sanguinis, Actinomyces naeslundii and Fusobacterium nucleatum was developed onto cpTi discs for 16.5 h (early biofilm) and 64.5 h (mature biofilm). The number of viable microorganisms and the composition of the extracellular matrix (proteins and carbohydrates) were determined. The biofilm organization was analyzed by scanning electron microscopy (SEM) and Confocal laser scanning microscopy (CLSM). In addition, MC3T3-E1 cells were cultured on the Ti surfaces and cell proliferation (MIT) and morphology (SEM) were assessed. MAO treatment produced oxide films rich in calcium and phosphorus with a volcano appearance while GDP treatment produced silicon-based smooth thin-film. Plasma treatments were able to increase the wettability of cpTi (p < 0.05). An increase of surface roughness (p <0.05) and formation of anatase and rutile structures was noted after MAO treatment. GDP had the greatest surface free energy (p <0.05) while maintaining the surface roughness compared to the machined control (p >0.05). Plasma treatment did not affect the viable microorganisms counts, but the counts of F. nucleaturn was lower for MAO treatment at early biofilm phase. Biofilm extracellular matrix was similar among the groups, excepted for GDP that presented the lowest protein content. Moreover, cell proliferation was not significantly affected by the experimental, except for MAO at 6 days that resulted in an increased cell proliferative. Together, these findings indicate that plasma treatments are a viable and promising technology to treat bone-integrated dental implants as the new surfaces displayed improved mechanical and biological properties with no increase in biofilm proliferation Ver menos