Intratubular Antibacterial Effect of Polyethyleneimine Nanoparticles: AnEx VivoStudy in Human Teeth

Abstract

Enterococcus faecalisis a facultative gram positive bacterium which can remain in the teeth root canals and cause refractory or persistent periapical diseases.E. faecalisbacteria that penetrate the dentinal tubules can be the source of intracanal infection and endodontic disease. Quaternary ammonium polyethyleneimine (QPEI) nanopolymers were shown to have long lasting antibacterial activity against gram positive and gram negative bacteria. The present study evaluated the intratubular antibacterial effect of an epoxy resin sealer incorporating 1% QPEI againstE. faecalisin a human dentin model. Root canals of extracted teeth were inoculated withE. faecalisfor 7 days prior to standard endodontic treatment. The antibacterial effect of an epoxy-amine resin endodontic sealer was tested at concentration of 0% or 1% (wt/wt) added QPEI nanoparticles. Reduction in bacterial viabilityp<0.01was depicted in the dentinal tubules of the root canals obturated with the sealer incorporating QPEI nanoparticles. In conclusion, QPEI nanoparticles when incorporated in a small percentage into epoxy-resin based sealer may targetE. faecalisin the dentinal tubules, producing a potent antibacterial effect that reduces significantly bacterial viability.