RESUMO
AIMS AND OBJECTIVES: The aim of this in vivo study was to evaluate the antibacterial efficacy of a diode LASER on the infected root canal system. METHODOLOGY: A total of forty patients with infected root canals were selected. The root canals were prepared mechanically, and irrigation was done with 3% sodium hypochlorite (NaOCl). Microbiological samples were collected before LASER treatment with the help of the master apical file (MAF) to full working length for subsequent microbiological examination. The procedure was followed by laser treatment with an EZLASE diode LASER (940 nm), at different output powers. Following irradiation, samples were collected for microbiological examination. The samples were transferred to an agar plate and incubated for 48 h at 37°C. The colonies formed were then counted, and the total number of bacteria per ml before and after LASER application was assessed. Colony-forming unit (CFU/ml) was counted for Enterococcus faecalis and other bacterial flora from pretreatment and posttreatment samples that were then analyzed using the Kruskal-Wallis test and Mann-Whitney U-test. RESULTS: The highest power of laser used (1.95 W) had resulted in maximum reduction of bacterial flora and E. faecalis counts. CONCLUSIONS: Combination therapy consisting of irrigation using NaOCl and LASER irradiation, especially at high output power was an effective treatment option for a reduction in E. faecalis as well as other bacterial flora from the root canal system.
