Effect on apical intracanal dentin after laser irradiation: A microleakage and scanning electron microscopic evaluation

Aim: The purpose of this in vitro study was to evaluate the effect of neodymium:Yttrium aluminum garnet (Nd:YAG) laser and diode laser irradiation on intracanal dentin surface by scanning electron microscopic (SEM) analysis, and its interference in the apical seal of filled canals. Materials and Methods: After endodontic treatment procedures, 60 single-rooted teeth were randomly assigned to four groups. In the negative control group (n = 15), no additional treatment was performed and teeth were filled with laterally condensed gutta-percha; in the Nd:YAG laser-treated group (n = 15) and in the diode laser-treated groups (n = 15), the root canals were irradiated with Nd:YAG laser -1.5 W/Diode laser 810 nm - 2 W /Diode laser 980 nm - 2 W } using 200 micron fiber before filling, as described for the control group. Two specimens of each group were prepared for SEM analysis to evaluate the presence and extent of morphological changes and removal of debris; the other specimens were immersed in 2% rhodamine B for 72 h at 37°C for evaluation of the linear dye leakage at the apical third. Results: Laser groups showed significantly less linear leakage as compared to the control group.