Bactericidal effect of the 908 nm diode laser on Enterococcus faecalis in infected root canals

The aim of this study is to evaluate the bactericidal effect of 908 nm diode laser in conjunction with various irrigation regimes in disinfection of apical third of root dentin. Sixty prepared teeth with single canals were contaminated with Enterococcus faecalis. The specimens were divided into 6 groups (n = 10): Group 1 and 3 and 5 were subjected to chemo-mechanical preparation using 5.25% sodium hypochlorite (NaOCl), 17% Ethylenediaminetetraacetic acid (EDTA); 1.3% NaOCl, MTAD (mixture of doxycycline, citric acid and a detergent (Tween 80); and, 8.5% saline, respectively followed by 908 nm diode laser irradiation; Group 2 and 4, followed the same procedure as Group1 and 3, however without laser irradiation; and, Group 6, rinsed with saline solution (control). Dentin shavings from apical third were analyzed for the presence of E. faecalis using culture method and Polymerase Chain reaction (PCR). One-way Analysis of variance showed statistically significant differences between the laser irradiated groups, non irradiated groups and the control group. 908 nm diode used in conjunction with conventional chemomechanical techniques demonstrated a significant elimination of E. faecalis in the apical third of root dentin.