Evaluation of apical leakage of root canals obturated with Nd: YAG laser-softened gutta-percha, System-B, and lateral condensation techniques.

In endodontics, a laser can be used as a heat source and gutta-percha can be softened by a laser and used in the root canals. The System-B endodontic heat source unit was designed for the obturation of the root canal system with a single continuous wave of thermoplasticized gutta-percha. The aim of this study was to compare the apical leakage of lateral condensation; Nd: YAG laser-softened gutta-percha and System-B techniques. Fifty-five extracted, single root human maxillary anterior and premolar teeth were used in this study. After working length determination, the "step-back technique" was used to prepare the root canals. The teeth were randomly divided into three experimental groups of 15 each and two control groups of 5 specimens each. The first group was obturated by lateral condensation, the second group by gutta-percha softened with an Nd: YAG laser, and the third group was obturated using the System-B technique. Apical leakage of the roots was evaluated by dye penetration using a stereomicroscope after sectioning the roots. The results of the first and third groups were similar, and the results of the second group showed differences when compared with the other groups. However, variance analysis revealed there was no statistically significant difference among the results.