title: The effect of various intracanal oxidizing agents on the push-out strength of various perforation repair materials.
abstract: OBJECTIVE
  The purpose of this study was to determine the effect of intracanal oxidizing agents on the strength of materials used to repair root perforations.
  
  
  METHODS
  Standardized perforations in bovine root samples were repaired with mineral trioxide aggregate (MTA), Super-EBA cement (S-EBA), or intermediate restorative material (IRM). After 7 days, 10 samples from each group were tested for push-out strength with an Instron machine (controls). The remaining samples were immersed in NaOCl, sodium perborate mixed with saline (SPB+S), Superoxol (SO), sodium perborate mixed with Superoxol (SPB+SO), or saline for 7 days to investigate the effect of irrigating and walking bleach compounds on the perforation repair materials. Push-out strength values were compared with those of the dry materials to determine whether any loss of integrity had occurred.
  
  
  RESULTS
  MTA was statistically significantly less resistant across conditions to displacement than S-EBA or IRM. IRM was consistent across treatment conditions, whereas S-EBA lost strength when exposed to NaOCl, SPB+S, or SPB+SO. Exposure to SPB+S had the greatest effect on all 3 materials.
  
  
  CONCLUSIONS
  IRM performed consistently as a perforation repair material despite exposure to oxidizing agents, whereas MTA was less resistant to dislodgement than either IRM or S-EBA and was more affected than IRM by sodium perborate-containing bleaching solutions.
authors.affiliation: Baumholder Dental Clinic, Baumholder, Germany.
authors.forename: Emine C
authors.initials: EC
authors.lastname: Loxley
authors.forename: Frederick R
authors.initials: FR
authors.lastname: Liewehr
authors.forename: T B
authors.initials: TB
authors.lastname: Buxton
authors.forename: J C
authors.initials: JC
authors.lastname: McPherson
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry; D000704:Analysis of Variance; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D001881:Borates / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry; D002417:Cattle; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry; D003786:Dental Pulp Cavity / Q000293:injuries; D003799:Dental Stress Analysis / Q000295:instrumentation; D004202:Disinfectants / Q000737:chemistry; D004338:Drug Combinations; D006861:Hydrogen Peroxide / Q000737:chemistry; D016555:Matched-Pair Analysis; D008422:Materials Testing; D008768:Methylmethacrylates / Q000737:chemistry; D016877:Oxidants / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D012387:Root Canal Filling Materials / Q000737:chemistry*; D012388:Root Canal Irrigants / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry; D012965:Sodium Chloride; D012973:Sodium Hypochlorite / Q000737:chemistry; D013314:Stress, Mechanical; D015035:Zinc Oxide-Eugenol Cement / Q000737:chemistry
chemical_list: D017607:Aluminum Compounds; D001672:Biocompatible Materials; D001881:Borates; D017610:Calcium Compounds; D003738:Dental Cements; D004202:Disinfectants; D004338:Drug Combinations; D008768:Methylmethacrylates; D016877:Oxidants; D010087:Oxides; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; D017640:Silicates; D015035:Zinc Oxide-Eugenol Cement; C086631:mineral trioxide aggregate; D012965:Sodium Chloride; C031667:IRM cement; D006861:Hydrogen Peroxide; D012973:Sodium Hypochlorite; C027707:sodium perborate