Role of diode and erbium, chromium, yttrium, scandium, gallium, and garnet lasers with ethylenediaminetetraacetic acid in smear layer removal, surface changes, and sealer penetration in root dentin: An in vitro study

Aim: The purpose of the study was to evaluate the smear layer (SL) removal, surface changes (SC), and root canal sealer penetration (SP) in root dentin at coronal, middle, and apical thirds following debridement with 17% ethylenediaminetetraacetic acid (EDTA) with and without diode and erbium, chromium, yttrium, scandium, gallium, and garnet (Er, Cr:YSGG) lasers. Methods: Eighty unirradicular permanent teeth were instrumented with ProTaper F4 rotary files and divided randomly into four groups based on the final irrigation protocol as saline ( n = 10), 17% EDTA ( n = 10), 17% EDTA + diode laser ( n = 30), and 17% EDTA + Er, Cr:YSGG laser ( n = 30). All samples were analyzed at coronal, middle, and apical third to measure the SC and SL removal using a scanning electron microscope and depth of SP (DSP) using confocal laser scanning microscopy. Comparative evaluation to assess the removal of SL was done statistically by Kruskal–Wallis nonparametric analysis of variance and DSP was assessed using one-way ANOVA and Tukey post h oc tests ( P < 0.02). Results: The results showed a statistically significant difference in SL removal and DSP when treated with a combination of 17% EDTA and lasers when compared to treating with 17% EDTA alone at all three levels of the root. Conclusion: The use of 17% EDTA with Er, Cr:YSGG followed by diode laser showed better SL removal and DSP when compared to 17% EDTA alone at all three root levels.