The bactericidal effect of Nd : YAG, Ho : YAG, and Er : YAG laser irradiation in the root canal: An in vitro comparison

Objective: The aim of this study was to compare the antibacterial effective ness of the Nd:YAG, the Ho:YAG, and the Er:YAG laser in infected root canal s. Summary Background Data: Lasers are gaining increasing importance in the field of endodontics, Numerous studies have shown the beneficial effects o f laser treatment in disinfecting root canals, Methods: In our in vitro exp erimental setup, 40 extracted and endodontically treated teeth were inocula ted with a suspension of Escherichia coli and Enterococcus faecalis and the n irradiated at standardized power settings. The disinfecting efficacy of e ach laser was proved by classical microbiological examination. Results: Thi s article highlights that all three lasers substantially decreased the bact erial population with only minimal differences in their microbicidal effica cy, At 1.5 W, the best results were obtained by the Er:YAG laser achieving a mean bacterial elimination of 99.64%, followed by the Nd:YAG laser (99.16 %), and the Ho:YAG laser (99.05%), Conclusion: Our findings indicate that a ll three lasers act as strongly effective microbicides without causing unfa vorable temperature rises at the settings used. They can thus be considered a valuable tool for root canal treatment.