title: Effects of root canal irrigants on the push-out strength and hydration behavior of accelerated mineral trioxide aggregate in its early setting phase.
abstract: BACKGROUND
  The purpose of this study was to evaluate the effects of endodontic irrigants on the push-out strength and hydration behavior of accelerated mineral trioxide aggregate (MTA) in its early setting phase.
  
  
  METHODS
  In an in vitro perforation model, MTA with or without 10% CaCl(2) was condensed and allowed to initial set for 10 minutes. The samples were divided into four groups (n = 10) to be immersed into either 3.5% sodium hypochlorite (NaOCl) or 2% chlorhexidine gluconate (CHX) for 30 minutes and then allowed to set for 48 hours. In the control group, a wet cotton pellet was placed over MTA. The maximum force applied to the set MTA mixture before dislodgement was recorded. Irrigant-treated surfaces were examined using a scanning electron microscope (SEM). Chemical elements of these surfaces were also analyzed by energy dispersive x-ray spectroscope (EDS).
  
  
  RESULTS
  The push-out strength of group A1 (NaOCl-treated accelerated MTA) was the highest of all groups. When compared with nonaccelerated MTA, CaCl(2)-accelerated MTA showed significantly higher push-out strength (p < 0.05). NaOCl-treated groups showed significantly higher push-out strength than CHX-treated groups (p < 0.05). Scanning electron microscopic examination and EDS analysis showed that the formation of calcium hydroxide crystals on accelerated MTA exposed to NaOCl was increased compared with those of the control group.
  
  
  CONCLUSIONS
  These findings imply that the use of accelerated MTA under the NaOCl irrigation was effective in perforation repair without altering its hydration behavior even in the early setting phase.
authors.affiliation: Department of Dentistry, School of Medicine, Ajou University, Suwon, Korea.
authors.forename: Seong-Tae
authors.initials: ST
authors.lastname: Hong
authors.forename: Kwang-Shik
authors.initials: KS
authors.lastname: Bae
authors.forename: Seung-Ho
authors.initials: SH
authors.lastname: Baek
authors.forename: Kee-Yeon
authors.initials: KY
authors.lastname: Kum
authors.forename: Won-Jun
authors.initials: WJ
authors.lastname: Shon
authors.forename: Woocheol
authors.initials: W
authors.lastname: Lee
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry / Q000627:therapeutic use; D000704:Analysis of Variance; D017610:Calcium Compounds / Q000737:chemistry / Q000627:therapeutic use; D002710:Chlorhexidine / Q000031:analogs & derivatives; D001840:Dental Bonding; D003762:Dental Instruments / Q000009:adverse effects; D003786:Dental Pulp Cavity / Q000293:injuries*; D003799:Dental Stress Analysis; D003804:Dentin / Q000737:chemistry / Q000648:ultrastructure; D004338:Drug Combinations; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010087:Oxides / Q000737:chemistry / Q000627:therapeutic use; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000627:therapeutic use*; D012388:Root Canal Irrigants; D017640:Silicates / Q000737:chemistry / Q000627:therapeutic use; D012973:Sodium Hypochlorite; D013052:Spectrometry, X-Ray Emission; D018709:Statistics, Nonparametric; D018677:Tooth Injuries / Q000188:drug therapy* / Q000209:etiology; D014092:Tooth Root / Q000293:injuries; D014867:Water
chemical_list: D017607:Aluminum Compounds; D017610:Calcium Compounds; D004338:Drug Combinations; D010087:Oxides; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; D017640:Silicates; C086631:mineral trioxide aggregate; D014867:Water; D012973:Sodium Hypochlorite; C010882:chlorhexidine gluconate; D002710:Chlorhexidine