Background: Golden standard of cleaning infected root canals with irrigants does not completely remove pathogens. The aim of our study was to estimate efficacy of Er:YAG laser compared to standard irrigation with NaOCl in infected root canals. Methods: 140 extracted premolar singlerooted teeth were used. The crowns were cut off so that we obtained 15 mm of root canal. Samples were divided into four groups and inoculated with Enterococcus faecalis, Candida albicans, Streptococcus sanguinis, Fusobacterium nucleatum. As disinfecting methods we performed Er:YAG laser radiation and irrigation with 5.20% NaOCl. Viability of microorganisms was analyzed using fluorescence by flow cytometry. Results: Both methods effectively eliminated major percent of microorganisms. Statistical differences were observed between tested organisms (p<0.05) for Er:YAG laser (30 and 90 seconds) and 5.20% NaOCl irrigation. The number of dead microorganisms was significantly higher for C. albicans and S. sanguinis than for E. faecalis or F. nucleatum. Longer duration of laser radiation of 90 seconds showed significant efficiency compared to 30-seconds radiation (p<0.001) and achieved over 80% of dead microbial cells. Disinfecting activity was even better in combination with irrigants and achieved over 90% in addition of NaOCl. Conclusions: Irradiation with Er:YAG laser could be used as a simple and standard disinfection method in endodontics, or even better can be used as as adjuvant therapy to standard and irrigation treatment.
The Efficacy of Erbium Laser in Infected Root Canals: ex vivo study