IADR Abstract Archives
Effect of Functionalized Nanoparticles in Biofilms on SLA Titanium Surfaces
Objectives: The aim of this study was to assess the antibacterial effect of active polymeric (PPA) nanoparticles (NPs), functionalized or not with calcium, zinc and doxycycline on titanium discs (TiD), in a validated in vitro subgingival biofilm model.
Methods: The biofilm model consisted of six bacterial species (Streptococcus oralis, Actinomyces naeslundii, Veillonela parvula, Fusobacterium nucleatum, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans). SLA (sandblasted, large grit, acid-etched) TiD were used with the application of NPs with calcium (Ca-NPs), zinc (Zn-NPs), doxycycline (Dox-NPs) and without charge (PPA-NPs), by friction with a micro-brush for 15 seconds. As control, sterile TiDs were used. All discs (n=9 in each group) were incubated under anaerobic conditions during 12, 24, 48 and 72 hours. To analyse the resulting biofilms, scanning electron microscopy (SEM) was used to study the structure of the biofilm, confocal laser scanning microscopy (CLSM) to assess the vitality and thickness, and quantitative polymerase chain reaction (qPCR) to evaluate the bacterial load, expressed as colony forming units (CFU) per mL. General linear models and Bonferroni adjustments were used to evaluate differences among groups.
Results: After 72 hours, PPA-NPs, Ca-NPs, Zn-NPs and Dox-NPs increased the mortality of bacterial cells in the biofilm (70.89%, 80.70%, 70.50% and 85.87%, respectively). Statistically significantly differences were found for dead cells, when compared to the control group (47.21%), for Ca-NPs (p<0.039) and PPA-NPs (p<0.045). Specifically, Dox-NPs were able to reduce the bacterial load of all studied bacteria, at different time points, with respect to the control group (TiD), except for Aggregatibacter actinomycetemcomitans.
Conclusions: Polymeric nanoparticles reduced the vitality and altered the dynamics of biofilm formation, and decreased the bacterial load in the case of Dox-NPs.
Methods: The biofilm model consisted of six bacterial species (Streptococcus oralis, Actinomyces naeslundii, Veillonela parvula, Fusobacterium nucleatum, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans). SLA (sandblasted, large grit, acid-etched) TiD were used with the application of NPs with calcium (Ca-NPs), zinc (Zn-NPs), doxycycline (Dox-NPs) and without charge (PPA-NPs), by friction with a micro-brush for 15 seconds. As control, sterile TiDs were used. All discs (n=9 in each group) were incubated under anaerobic conditions during 12, 24, 48 and 72 hours. To analyse the resulting biofilms, scanning electron microscopy (SEM) was used to study the structure of the biofilm, confocal laser scanning microscopy (CLSM) to assess the vitality and thickness, and quantitative polymerase chain reaction (qPCR) to evaluate the bacterial load, expressed as colony forming units (CFU) per mL. General linear models and Bonferroni adjustments were used to evaluate differences among groups.
Results: After 72 hours, PPA-NPs, Ca-NPs, Zn-NPs and Dox-NPs increased the mortality of bacterial cells in the biofilm (70.89%, 80.70%, 70.50% and 85.87%, respectively). Statistically significantly differences were found for dead cells, when compared to the control group (47.21%), for Ca-NPs (p<0.039) and PPA-NPs (p<0.045). Specifically, Dox-NPs were able to reduce the bacterial load of all studied bacteria, at different time points, with respect to the control group (TiD), except for Aggregatibacter actinomycetemcomitans.
Conclusions: Polymeric nanoparticles reduced the vitality and altered the dynamics of biofilm formation, and decreased the bacterial load in the case of Dox-NPs.