OR19 - All-in-one Irrigation Solution Shows Higher Antimicrobial Efficacy Than Sodium Hypochlorite in Single and Mixed Species Endodontic Biofilm Models

Abstract: Objectives: To evaluate the antibiofilm efficacy of a new all-in-one irrigation solution (Triton) in comparison with 4% NaOCl, on E.faecalis biofilms grown in the MBEC high-throughput device and mixed species biofilm grown in an oraganotypic root canal model. Materials and Methods: Experiments were conducted in two phases; Phase-1: 48 h E.faecalis biofilms were grown in the MBEC device at 37°C and 5% CO2. Biofilms were exposed to serial two-fold dilutions of each irrigating solution for 10 seconds. Biofilms were also exposed to irrigants in the presence of dentin powder. A concentration of an irrigant was considered to eradicate the biofilms when it produced no visible growth on blood agar. Phase-2: Mixed species biofilm composed of E. faecalis, S. gordonii and F. nucleatum was grown in an organotypic ex vivo root canal biofilm model for 7 days in an anaerobic condition. Biofilms were exposed to 2 ml of irrigants for 10 minutes. Viable counts of remaining bacteria were evaluated by means of colony-forming-units (CFU). Results: NaOCl and Triton showed similar antimicrobial efficacy at concentrations 4%, 2% and 1%. However, at 0.5% concentration NaOCl showed complete eradication while Triton didn’t. Presence of dentin affected 4% NaOCl but not Triton. Triton showed higher efficacy in reducing viable bacterial count compared to 4% NaOCl (mean CFU E.faecalis 1.14e+06 vs 5.4e+05; S.gordonii 5.54e+4 vs 2.5e+4; F. nucleatum 1.25e+3 vs below detection limit) respectively in the organotypic model. Conclusions: Our data shows promising results of all-in-one irrigation solution for disruption and reduction of endodontic biofilm bacteria.