title: The effect of obturation technique on the push-out bond strength of calcium silicate sealers.
abstract: BACKGROUND
  Calcium silicate-based sealers are known to have excellent sealing ability and bioactivities. They are typically recommended to be used in a single-cone (SC) technique. No studies have evaluated the effects of the thermoplastic obturation technique on the dentin interface of these sealers. The purpose of this study was to evaluate the push-out bond strengths of MTA Plus Sealer (Avalon Biomed Inc, Bradenton, FL) and EndoSequence BC Sealer (BC; Brasseler USA, Savannah, GA) when they were used in a thermoplastic technique.
  
  
  METHODS
  Fifty single-rooted human extracted teeth were randomly divided into 5 groups (n = 10), instrumented, and obturated with the SC technique or continuous wave (CW) technique: group 1, BC-SC; group 2, BC-CW; group 3, MTA Plus-SC; group 4, MTA Plus-CW; and group 5, AH Plus (Dentsply DeTrey, Konstanz, Germany)-CW. The roots were sectioned into 1.0-mm-thick slices, and bond strengths were measured using a standardized push-out test. The mode of failure was determined by visual inspection under magnification.
  
  
  RESULTS
  The MTA Plus-CW had statistically significant lower bond strengths than all other groups. The BC-SC group had statistically higher bond strengths than the MTA Plus-SC and AH Plus-CW groups. No significant differences were seen among the other groups. Modes of failure were predominately cohesive or mixed except for group 4 (ie, MTA Plus-CW) in which nearly half the specimens had no visible sealer.
  
  
  CONCLUSIONS
  BC and MTA Plus sealer showed favorable bond strengths when used in an SC technique. The CW obturation technique decreased the bond strengths of these sealers.
authors.affiliation: Department of Endodontics, Texas A&M University Baylor College of Dentistry, Dallas, Texas.
authors.forename: Christopher
authors.initials: C
authors.lastname: DeLong
authors.affiliation: Department of Endodontics, Texas A&M University Baylor College of Dentistry, Dallas, Texas. Electronic address: jhe@bcd.tamhsc.edu.
authors.forename: Jianing
authors.initials: J
authors.lastname: He
authors.affiliation: Department of Endodontics, Texas A&M University Baylor College of Dentistry, Dallas, Texas.
authors.forename: Karl F
authors.initials: KF
authors.lastname: Woodmansey
mesh_terms: D017610:Calcium Compounds / Q000494:pharmacology*; D001840:Dental Bonding / Q000379:methods*; D003799:Dental Stress Analysis / Q000379:methods*; D006801:Humans; D012387:Root Canal Filling Materials / Q000494:pharmacology*; D012389:Root Canal Obturation / Q000379:methods*; D017640:Silicates / Q000494:pharmacology*; D014070:Tooth / Q000187:drug effects
chemical_list: D017610:Calcium Compounds; D012387:Root Canal Filling Materials; D017640:Silicates; C031293:calcium silicate
keywords: Bond strength; EndoSequence BC Sealer; MTA Plus; continuous wave; push-out test