Acta Scientific Dental Sciences (ISSN: 2581-4893)

Research Article Volume 4 Issue 2

Evaluation of Competency of Diode Laser and Er: YAG Laser Activation on Sodium Hypochlorite Capability for Biofilm Eradication and Smear Layer Removal: A Comparative In vitro Study

Radhwa Refaat Otaify1*, Nehal Nabil Roshdy2 and Nihal Ezzat Sabet3

1Masters Student, Faculty of Dentistry, Cairo University, Egypt
2Associate Professor of Endodontics, Faculty of Dentistry, Cairo University, Egypt
3Professor Of Endodontics, Faculty of Dentistry, Cairo University, Egypt

*Corresponding Author: Radhwa Refaat Otaify, Masters Student, Faculty of Dentistry, Cairo University, Egypt.

Published: January 11, 2020



Objective: This study attempted to evaluate the efficacy of Sodium hypochlorite activation using two types of laser; Diode laser and Er: YAG laser utilizing PIPS tip as compared to conventional Sodium hypochlorite syringe irrigation on biofilm eradication, smear layer removal and topographic surface changes.

Methods: For biofilm eradication analysis, 21 single-rooted premolar human teeth were prepared and inoculated with E. faecalis, then divided into three groups of seven roots each. All teeth were subjected to irrigation with 10 ml 2.5% Sodium hypochlorite either with, conventional syringe irrigation (CSI) in Group I, Diode laser activation (940 nm) in Group II, or Er: YAG laser activation utilizing PIPS tip in Group III. Biofilm eradication was evaluated using Confocal Laser Scanning Microscope CLSM. For comparing the smear removal efficacy and surface topographic changes, another 21 single-rooted premolar human teeth, were irrigated with saline during instrumentation and assigned to three groups as mentioned. Scanning Electron microscope was used to score the presence of a smear layer at different root canal levels and analyze the topographic surface changes by detecting the presence of dentinal tubules changes.

Results: Er: YAG Group utilizing PIPS tip showed significantly higher biofilm eradication when compared to CSI Group and Diode laser activation Group (p < 0.0001 and 0.004 respectively). SEM analysis presented Group III with significantly higher smear layer removal in the coronal and middle thirds as compared to the other two Groups (p = 0.031). Analysis of topographic surface changes showed a statistically significant higher incidence of dentinal tubules changes in both laser activation groups when compared to CSI only in the coronal third (p = 0.04).

Conclusions: Activation of Sodium hypochlorite irrigant using Er: YAG laser utilizing PIPS technique enhanced the biofilm eradication capability and smear layer elimination potentiality. Yet, the dentinal tubules changes remain higher when laser is used.

Keywords: LAI Laser Activated Irrigation; PIPS Photon Initiated Photoacoustic Streaming; Biofilm Smear Layer; Dentin Changes; Irrigation; Confocal Laser Microscopy; Scanning Electron Microscope



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Citation: Radhwa Refaat Otaify., et al. “Evaluation of Competency of Diode Laser and Er: YAG Laser Activation on Sodium Hypochlorite Capability for Biofilm Eradication and Smear Layer Removal: A Comparative In vitro Study”.Acta Scientific Dental Sciences 4.2 (2020): 28-36.


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