NANO-ENGINEERED IRRIGATING SOLUTIONS AND LASERS – AN ANTIBACTERIAL STUDY AGAINST ENTEROCOCCUS FAECALIS

BACKGROUND: Enterococcus faecalis (E. faecalis) is the most commonly detected micro-organism in asymptomatic and persistent endodontic infections. Thorough disinfection of the root canal is more important than proper shaping for a successful endodontic treatment. This study is an attempt to implement nanoparticles which have proven anti-bacterial efficacy as irrigating solutions against E. faecalis. AIM: To compare and evaluate the anti-bacterial efficacy of 5% sodium hypochlorite (NaOCl), 0.2% chitosan nanoparticles solution (ChNP) and 0.01% silver nanoparticles solution (AgNP) against E.faecalis with and without diode laser activation. MATERIALS AND METHODS: 70 single rooted mandibular premolars were included in this study. Access opening, working length determination and biomechanical preparation were standardized. Samples were embedded in putty material inside an eppendorf tube to simulate periodontal ligament and autoclaved followed by inoculation of  E.faecalis (MTCC 439) and incubated at 37℃ for 7 days. The samples were divided into 7 groups (10 samples in each group). Group 1- No treatment (Negative control), group 2 - 5% NaOCl without activation (Positive control), group 3 - 5% NaOCl with diode laser activation, group 4-  0.01% AgNP without activation, group 5- 0.01% AgNP with diode laser activation, group 6- 0.2% ChNP without activation and group 7- 0.2% ChNP with diode laser activation. A final rinse of the respective irrigants and activation were performed, followed by counting the colony forming units.  Statistical analysis used were one-way analysis of variance (ANOVA) followed by Tukey’s post-hoc tests. Results showed that diode laser in combination with 5% NaOCl and 0.2% ChNP had significant effects in the reduction of microbial colony counts of E. faecalis in comparison to other experimental groups.  Keywords: Nanoparticles, Irrigation, LASER, Enterococcus faecalis