Effect of ultrasonic activation on calcium ion quantification, smear layer removal, and canal cleaning efficacy of demineralizing irrigants

J Conserv Dent. 2018 Sep-Oct;21(5):551-556. doi: 10.4103/JCD.JCD_162_18.

Abstract

Background: Effective removal of smear layer ensures better penetration of irrigants ensuring root canal disinfection and has the potential of sealing dentinal tubules during obturation.

Aim: The aim of this study is to evaluate the canal cleaning efficacy and calcium ion liberation with the use of demineralizing irrigants, namely, 17% ethylenediaminetetraacetic acid (EDTA), 7% maleic acid, and 10% citric acid with or without ultrasonic (US) activation.

Materials and methods: Crowns of 62 extracted maxillary central incisors were decoronated and root canals prepared. Based on the final irrigant teeth were divided into following groups (n = 10), namely, 10% citric acid, 7% maleic acid, 17% EDTA, and 10% citric acid with US activation, 7% maleic acid with US activation, and 17% EDTA with US activation. Irrigants were subjected to inductively coupled plasma-atomic emission spectroscopy followed by debris scoring and scanning electron microscope analysis.

Statistical analysis: One-way analysis of variance with the Bonferroni's correction for multiple testing was employed.

Results: About 10% citric acid with US activation liberated the highest calcium ions and removed the maximum smear layer.

Conclusions: Citric acid with US activation is a potentially effective irrigation regimen with sodium hypochlorite.

Keywords: Chelators; citric acid; inductively coupled plasma-atomic emission spectroscopy; irrigants; smear layer.