title: A comparative evaluation of smear layer removal by using edta, etidronic acid, and maleic acid as root canal irrigants: An in vitro scanning electron microscopic study.
abstract: OBJECTIVE
  The purpose of this study is to evaluate and compare the efficacy of 17% EDTA, 18% etidronic acid, and 7% maleic acid in smear layer removal using scanning electron microscopic image analysis.
  
  
  METHODS
  Thirty, freshly extracted mandibular premolars were used. The teeth were decoronated to obtain working length of 17mm and instrumentation up to 40 size (K file) with 2.5% NaOCl irrigation between each file. The samples were divided into Groups I (17% ethylenediaminetetraacetic acid (EDTA)), II (18% etidronic acid), and III (7% maleic acid) containing 10 samples each. Longitudinal sectioning of the samples was done. Then the samples were observed under scanning electron microscope (SEM) at apical, middle, and coronal levels. The images were scored according to the criteria: 1. No smear layer, 2. moderate smear layer, and 3 heavy smear layer.
  
  
  METHODS
  Data was analyzed statistically using Kruskal-Wallis analysis of variance (ANOVA) followed by Mann-Whitney U test for individual comparisons. The level for significance was set at 0.05.
  
  
  RESULTS
  The present study showed that all the three experimental irrigants removed the smear layer from different tooth levels (coronal, middle, and apical). Final irrigation with 7% maleic acid is more efficient than 17% EDTA and 18% etidronic acid in the removal of smear layer from the apical third of root canal.
authors.affiliation: Department of Endodontics, Hassanaba Dental College, Vidhya Nagar, Hassan, Karnataka, India.
authors.forename: Aby
authors.initials: A
authors.lastname: Kuruvilla
authors.affiliation: Department of Endodontics, Hassanaba Dental College, Vidhya Nagar, Hassan, Karnataka, India.
authors.forename: Bharath Makonahalli
authors.initials: BM
authors.lastname: Jaganath
authors.affiliation: Department of Endodontics, Hassanaba Dental College, Vidhya Nagar, Hassan, Karnataka, India.
authors.forename: Sahadev Chickmagaravalli
authors.initials: SC
authors.lastname: Krishnegowda
authors.affiliation: Department of Endodontics, Hassanaba Dental College, Vidhya Nagar, Hassan, Karnataka, India.
authors.forename: Praveen Kumar Makonahalli
authors.initials: PK
authors.lastname: Ramachandra
authors.affiliation: Department of Endodontics, Kunhitharuvai Memorial Charitable Trust (KMCT) Dental College, Calicut, India.
authors.forename: Dexton Antony
authors.initials: DA
authors.lastname: Johns
authors.affiliation: Department of Orthodontics, Government Dental College, Kottayam, Kerala, India.
authors.forename: Aby
authors.initials: A
authors.lastname: Abraham
keywords: EDTA; Smear layer; etidronic acid; maleic acid; Scanning electron microscope SEM