Doxycycline‐functionalized polymeric nanoparticles inhibit Enterococcus faecalis biofilm formation on dentine

Aim To evaluate in a laboratory setting the antimicrobial properties and the potential to inhibit biofilm formation of novel remineralizing polymeric nanoparticles (NPs) when applied to dentine surfaces and to ascertain the effect of the functionalization of these NPs with zinc, calcium or doxycycline. Methodology The antimicrobial activity and inhibition of biofilm formation of polymeric NPs were analysed on human dentine blocks that were infected with Enterococcus faecalis before or after application of NPs. LIVE/DEAD ® testing under Confocal Laser Scanning Microscopy and bacterial culturing were employed to analyse biofilm biovolume and bacterial viability. Field Emission Scanning Electron Microscopy was also employed to assess biofilm morphology. One‐way anova with Welch’s correction and post hoc comparison by the Games–Howell test were performed for comparisons between groups. Results The un‐functionalized NPs displayed the greatest antimicrobial activity against E. faecalis biofilms as they provided the lowest biovolume (3865.7 ± 2926.97 µm3; P