title: The effect of surfactant addition to EDTA on microhardness of root dentin.
abstract: BACKGROUND
  The aim of this study was to investigate the effect of different concentrations of cetrimide with or without 5% EDTA solution on the microhardness of human root dentin in vitro.
  
  
  METHODS
  Twenty-five recently extracted single-rooted human teeth were selected. The roots were split longitudinally into 2 parts. The specimens were randomly divided into the following 5 groups and were treated with 5% EDTA, 5% EDTA + 0.25% cetrimide, 5% EDTA + 0.50% cetrimide, 0.25% cetrimide, and 0.50% cetrimide immediately after the initial baseline microhardness measurements. A standardized volume of 50 mL of each solution was used for 1 minute. The reference microhardness values of untreated specimens were initially measured with a Vickers indenter under a 50-g load and a 10-second dwell time at the midroot level of the root dentin. Post-treatment microhardness values were obtained in the same manner as the initial ones. The decrease in microhardness was calculated as a percentage. Data were analyzed statistically by 1-way analysis of variance (P = .05) and the post hoc Tukey test for multiple comparisons at the same level of significance.
  
  
  RESULTS
  All solutions significantly decreased the microhardness of root dentin (P < .05). Although there was no significant difference among the solutions (P > .05), the specimens in the EDTA + 0.50% cetrimide solution group showed the highest change in microhardness. The plain EDTA and plain 0.50% cetrimide groups had similar values.
  
  
  CONCLUSIONS
  The use of surfactants higher than 0.25% in concentration is questionable for clinical conditions.
authors.affiliation: Department of Endodontology, School of Dentistry, Ege University, Izmir, Turkey. ilgin.akcay@ege.edu.tr
authors.forename: Ilgin
authors.initials: I
authors.lastname: Akcay
authors.forename: Bilge H
authors.initials: BH
authors.lastname: Sen
mesh_terms: D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry / Q000494:pharmacology*; D003786:Dental Pulp Cavity / Q000187:drug effects* / Q000648:ultrastructure; D003804:Dentin / Q000187:drug effects* / Q000648:ultrastructure; D004492:Edetic Acid / Q000737:chemistry / Q000494:pharmacology*; D006244:Hardness; D006801:Humans; D008422:Materials Testing; D010784:Photomicrography; D012388:Root Canal Irrigants / Q000737:chemistry / Q000494:pharmacology*; D016369:Smear Layer; D013501:Surface-Active Agents / Q000737:chemistry / Q000494:pharmacology*; D013997:Time Factors; D014092:Tooth Root / Q000187:drug effects / Q000648:ultrastructure
chemical_list: D002593:Cetrimonium Compounds; D012388:Root Canal Irrigants; D013501:Surface-Active Agents; D004492:Edetic Acid; D000077286:Cetrimonium