Evaluation of Penetration Depth of Sodium Hypochlorite Into Dentinal Tubules After Passive Ultrasonic Irrigation Compared to Er;Yag Laser Activation. An In-Vitro Study

Abstract

Objectives: The aim of this study was to compare penetration depth of sodium hypochlorite into dentinal tubules after passive ultrasonic agitation or ER; YAG activated irrigant.Materials and Methods: Twenty-four single rooted human mature mandibular premolars were decoronated and accessed. After locating the apex and determining the working length, preparation of root canal was done up to #35 file using Mtwo system and with 5.25 NaOCl irrigation. Teeth were then sealed apically with wax and submerged in a crystal violet dye for 48 hours to stain dentin. NaOCl Irrigation was activated with either Ultrasonic or ER;YAG laser. Specimens were sectioned longitudinally and depth of bleached zone was evaluated under a stereomicroscope 40X.Results: Penetration depth was significantly higher in overall root canal in ultrasonic group than ER; YAG laser group (P=.000). In ER;YAG Laser group, the highest penetration depth was in the coronal third followed by middle and third, with significant difference between apical third and both middle and coronal thirds (P=.009, .003 respectively), and no significant difference between middle and coronal thirds (P=.083). Highest penetration depth was seen in middle third for no significant deference in penetration depth between the three thirds of the root canal activated with Ultrasonic (P=.664). Conclusion: ultrasonic activation can lead to more NaOCl penetration into dentinal tubules than activation with ER;YAG.

Keywords

• penetration depth
• passive ultrasonic agitation
• er;yag
• laser activated irrigant