title: Bond strength of AH Plus and Epiphany sealers on root dentine irradiated with 980 nm diode laser.
abstract: OBJECTIVE
  To evaluate the bond strength of AH Plus and Epiphany sealers to human root canal dentine irradiated with a 980 nm diode laser at different power and frequency parameters, using the push-out test.
  
  
  METHODS
  Sixty canine roots were sectioned below the cementoenamel junction to provide 4-mm-thick dentine discs that had their root canals prepared with a tapered bur and irrigated with sodium hypochlorite, ethylenediaminetetraacetic acid and distilled water. The specimens were assigned to five groups (n = 12): one control (no laser) and four experimental groups that were submitted to 980 nm diode laser irradiation at different power (1.5 and 3.0 W) and frequency (continuous wave and 100 Hz) parameters. Half of specimens in each group had their canals filled with AH Plus sealer and half with Epiphany. The push-out test was performed and data (MPa) were analysed statistically by anova and Tukey's test (P < 0.05). The specimens were split longitudinally and examined under SEM to assess the failure modes after sealer displacement.
  
  
  RESULTS
  The specimens irradiated with the diode laser and filled with AH Plus had significantly higher bond strength values (8.69 +/- 2.44) than those irradiated and filled with Epiphany (3.28 +/- 1.58) and the nonirradiated controls (3.86 +/- 0.60). The specimens filled with Epiphany did not differ significantly to each other or to the control (1.75 +/- 0.69). There was a predominance of adhesive failures at Epiphany-dentine interface (77%) and mixed failures at AH Plus-dentine interface (67%).
  
  
  CONCLUSIONS
  The 980 nm diode laser irradiation of root canal dentine increased the bond strength of AH Plus sealer, but did not affect the adhesion of Epiphany sealer.
authors.affiliation: School of Dentistry, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Alfredo
authors.forename: S R C
authors.initials: SR
authors.lastname: Silva
authors.forename: J E V
authors.initials: JE
authors.lastname: Ozório
authors.forename: M D
authors.initials: MD
authors.lastname: Sousa-Neto
authors.forename: A
authors.initials: A
authors.lastname: Brugnera-Júnior
authors.forename: Y T C
authors.initials: YT
authors.lastname: Silva-Sousa
mesh_terms: D000268:Adhesiveness; D003481:Cuspid; D001840:Dental Bonding; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D003804:Dentin / Q000528:radiation effects*; D017220:Dentin-Bonding Agents; D004853:Epoxy Resins; D006801:Humans; D054023:Lasers, Semiconductor; D012387:Root Canal Filling Materials; D018915:Root Canal Preparation
chemical_list: D017220:Dentin-Bonding Agents; D004853:Epoxy Resins; D012387:Root Canal Filling Materials; C486893:epiphany sealer; C534916:epoxy resin-based root canal sealer