World Journal of Dentistry

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VOLUME 14 , ISSUE 3 ( March, 2023 ) > List of Articles


Comparative Efficacy of Er:YAG Laser and Shock Wave Enhanced Emission Photoacoustic Streaming (SWEEPS) for Smear Layer Removal: An Ex Vivo Study

Amir Jamali, Mehrfam Khoshkhounejad, Nasim Chiniforush, Amirhossein V Razlighi, Farshad Khosraviani, Pegah Sarraf

Keywords : Endodontics, Laser, Smear layer

Citation Information : Jamali A, Khoshkhounejad M, Chiniforush N, Razlighi AV, Khosraviani F, Sarraf P. Comparative Efficacy of Er:YAG Laser and Shock Wave Enhanced Emission Photoacoustic Streaming (SWEEPS) for Smear Layer Removal: An Ex Vivo Study. World J Dent 2023; 14 (3):220-227.

DOI: 10.5005/jp-journals-10015-2213

License: CC BY-NC 4.0

Published Online: 05-05-2023

Copyright Statement:  Copyright © 2023; The Author(s).


Aim: This study aimed to compare the efficacy of conventional syringe irrigation (CSI), erbium-doped yttrium aluminum garnet (Er:YAG) light amplification by the stimulated emission of radiation (laser), and shock wave enhanced emission photoacoustic streaming (SWEEPS) for smear layer removal. Materials and methods: In this ex vivo study, the smear layer was removed from the root canals of 36 extracted single-canal teeth in six groups by using the following modalities—ethylenediaminetetraacetic acid (EDTA) + sodium hypochlorite (NaOCl), NaOCl + EDTA + Er:YAG laser, NaOCl + EDTA + SWEEPS, distilled water + Er:YAG laser, distilled water + SWEEPS, and distilled water alone. In all laser groups, Er:YAG laser (Fontana, Slovenia) was used with 20 mJ energy for 20 seconds. The laser was irradiated with 0.3 W power with 50 µseconds pulse width and 15 Hz frequency for 20 seconds with air and water spray in off mode. The amount of smear layer was quantified under a scanning electron microscope (SEM) at ×1000 magnification using a 5-point scoring system. Data were analyzed by the Kruskal–Wallis test. The p-value was set at <0.05. Results: A significant difference was noted in smear layer removal between the EDTA groups and distilled water groups (p < 0.001). However, the difference was not significant between the EDTA groups with each other or between the distilled water groups with each other (p > 0.05). In EDTA groups, laser activation of irrigant and use of SWEEPS mode showed better smear scores in the middle and apical thirds. Conclusion: According to the limitation of the present study, Er:YAG laser and SWEEPS technique can remove the smear layer effectively in the presence of EDTA. SWEEPS mode of Er:YAG laser can serve as a suitable alternative to the conventional Er:YAG laser and CSI for smear layer removal from the hard-to-reach areas of the root canal system. Clinical significance: Using Er:YAG or SWEEPS technique was comparatively efficient in cleaning the smear layer, and it can be used for effective removal of the smear layer for clinical usage.

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