Abstract
Purpose
The aim of this quantitative study was to compare between a dual-wavelength laser (Er,Cr:YSGG, diode 940 nm) to the XP-Endoshaper/finisher combined with ethylenediaminetetraacetic acid (EDTA) 17% technique in removing secondary smear layer created during endodontic retreatment of curved canals.
Methods
Twenty-four human curved root canals were endodontically prepared and filled with AH-sealer and Reciproc® Gutta percha cones. The fillings were removed after 6 weeks, and the samples were randomly divided into 3 groups: A, negative control: irrigated with distilled water; B, XP-Endoshaper/finisher with EDTA 17%; and C Er,Cr:YSGG (2 W, 20 Hz, 50 μs) and diode 940 nm (2 W, 50% duty cycle). The canals were split longitudinally, and a laser scanning microscope (VK-X100K, VK-X200K, Keyence, Osaka, Japan) was used to capture images with the magnification of × 1000 from the canals. The images were scored by three blinded dentists using the Hülsmann scoring system, and a statistical analysis was carried out.
Results
A significant difference between the apical regions of groups B and C (p = 0.0010) was observed, with group C showing a cleaner apical region. However, this difference is cancelled out when comparing all areas of the canals (t = 1.43, df 21 p = 0.1663).
Conclusion
Within the limitations of this study, it can be concluded that a dual laser wavelength protocol (Er,Cr:YSGG (2 W, 20 Hz, 50 μs) and diode 940 nm (2 W, 50% duty cycle) may be positive in removing the secondary smear layer formed during endodontic retreatment cases of curved root canals.
Endodontic retreatment of curved root canals using the dual wavelength erbium, chromium:yttrium, scandium, gallium, garnet, and diode 940-nm lasers and the XP-Endoshaper/finisher technique