Antibacterial activity and biocompatibility of magnesium oxide coating prepared on micro-arc oxidized titanium by electrophoretic deposition

Titanium (Ti) dental implants face risks of early failure due to bacterial adhesion and biofilm formation. It is thus necessary to endow the implant surface with antibacterial ability. In this study, magnesium oxide (MgO) coatings were prepared on Ti by combining micro-arc oxidation (MAO) and electrophoretic deposition (EPD). The MgO nanoparticles homogeneously deposited on the microporous surface of MAO-treated Ti, yielding increasing coverage with the EPD time increased to 15 to 60 s. After co-culture with Porphyromonas gingivalis for 24 h and 72 h, the coatings produced antibacterial rates of 4–53% and 39–79%, respectively. Electron and fluorescence microscopies revealed that, both the density of adherent bacterial adhesion on the surface and the proportion of viable bacteria decreased with the EPD time. The morphology of cells on the surface of each group was intact and there was no significant difference among the groups. These results show that, the MgO coatings deposited on MAO-treated Ti by EPD had reasonably good in vitro antibacterial properties and cytocompatibility.