title: A comparative evaluation of smear layer removal using two rotary instrument systems with ethylenediaminetetraacetic acid in different states: a SEM study.
abstract: OBJECTIVE
  The aim of the study was to evaluate the ability of 17% ethylenediaminetetraacetic acid (EDTA) solution and 19% EDTA gel to remove debris, and smear layer produced during root canal preparation with two NiTi files systems, Mtwo and Protaper.
  
  
  METHODS
  Twenty freshly extracted human anterior teeth with single root canal were collected. The crowns were sectioned at the cemento-enamel junction, and working length was measured. These samples were randomly divided into four groups of five samples each. In each group, 2 ml of 3 % sodium hypochlorite solution was used with first instrument. The groupings were as follows. Group 1: 2 ml of 17% EDTA solution and 2 ml of 3% NaOCl were used alternatively each time a new file was employed. This group was prepared with Mtwo rotary files. Group 2: The samples in this group was prepared with Mtwo rotary files. EDTA gel (19%) was used and the samples were irrigated with 2 ml of 3% NaOCl. NaOCl and EDTA gel were used alternatively. Group 3: Five samples were prepared with Protaper file. Irrigation regime was the same as in Group 1. Group 4: Five samples were prepared with Protaper files and irrigation regime was the same as in Group 2. SEM study was done and the collected data were submitted for statistical analysis.
  
  
  RESULTS
  There was no statistically significant difference with the varied instruments used (Mtwo and Protaper files), and 17% EDTA solution and 19% EDTA gel.
  
  
  CONCLUSIONS
  Both the NITI instruments produced a similar dentin surface on root canal wall when used with EDTA gel and EDTA solution.
authors.affiliation: Department of Conservative Dentistry & Endodontics, Faculty of Dental Sciences, Chhatrapati Shahuji Maharaj Medical University (earlier KGMC), Lucknow, India. drkkwadhwani@yahoo.com
authors.forename: K K
authors.initials: KK
authors.lastname: Wadhwani
authors.forename: A P
authors.initials: AP
authors.lastname: Tikku
authors.forename: Anil
authors.initials: A
authors.lastname: Chandra
authors.forename: Vijay Kumar
authors.initials: VK
authors.lastname: Shakya
mesh_terms: D002614:Chelating Agents / Q000008:administration & dosage; D003762:Dental Instruments; D003786:Dental Pulp Cavity / Q000187:drug effects* / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D004492:Edetic Acid / Q000008:administration & dosage*; D004867:Equipment Design; D005782:Gels; D006801:Humans; D012388:Root Canal Irrigants / Q000008:administration & dosage*; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods*; D016369:Smear Layer; D012996:Solutions; D013499:Surface Properties
chemical_list: D002614:Chelating Agents; D005782:Gels; D012388:Root Canal Irrigants; D012996:Solutions; D004492:Edetic Acid