A Comparative evaluation of smear layer removal using: sonic, ultrasonic, and erbium, chromium: yttrium scandium gallium garnet Laser as activated irrigation techniques (an SEM study) .


  • Dara Zakaria Shakir Department of Conservative Dentistry, College of Dentistry, Hawler Medical University, Erbil, Iraq.
  • Ihsan Neimat Bahnam Department of Conservative, College of Dentistry, Hawler Medical University, Erbil, Iraq.




Irrigation, Smear layer, Sonic, Ultrasonic, Laser


Background and Objectives: In root canal treatment it is important to provide a reliable method that effectively removes the smear layer to ensure more successful results in endodontic treatment. This study aims to compare the efficacy of different irrigant activation methods (sonic, ultrasonic, and erbium, chromium: yttrium scandium gallium garnet Er,Cr:YSGG—2780nm laser) for the removal of smear layer at coronal, middle, and apical one-third of the root canal surface.

Methods: Sixty single-rooted mandibular premolar teeth were selected and instrumented to size 25/.08 (HyFlex EDM, Coltene). Samples were randomly divided into 4 groups of 15 roots each, depending on the system used to activate the irrigant solution. Group1, conventional needle irrigation with no activation (control), Group2 activated by EndoActivator (sonic group), Group3 activated by UltraX activator (ultrasonic group), and Group4 activated by Er,Cr:YSGG laser (laser group). Samples were irrigated with 1ml of EDTA 17% for 1 minute, then received 5ml of NaOCl 5.25% and activated for 1 minute. Scanning electron microscope investigations were conducted to evaluate the efficacy of suggested treatments.

Results: The laser group showed the least smear layer scores, followed by ultrasonic and then sonic groups with no statistically significant differences. All groups revealed better smear layer removal compared to the control group with significant differences at (p-value < 0.05).

Conclusion: All the activation techniques were useful in the removal of the smear layer with the favorite to laser technology that was the best one. Smear layer removal was more effective in the coronal and middle thirds than in the apical third for all groups.



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How to Cite

Shakir DZ, Bahnam IN. A Comparative evaluation of smear layer removal using: sonic, ultrasonic, and erbium, chromium: yttrium scandium gallium garnet Laser as activated irrigation techniques (an SEM study) . EDJ [Internet]. 2023 Jun. 30 [cited 2024 May 18];6(1):39-4. Available from: https://edj.hmu.edu.krd/index.php/journal/article/view/209



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