title: Effect of eugenol exposure time and post-removal delay on the bond strength of a self-etching adhesive to dentin.
abstract: OBJECTIVE
  This study evaluated the effects of the exposure time of eugenol-based provisional restorative material and the time elapsed between the provisional material removal and the adhesive procedure on the bond strength of the composite to dentin.
  
  
  METHODS
  Human third molars were sectioned into two halves that were enclosed in resin cylinders. The cavities were prepared over the buccal/lingual faces with diamond burs. Zinc oxide and eugenol (ZOE) provisional material was inserted into cavities and left for 24 hours, 7 days or 14 days. The cavities not restored with ZOE were used as controls. After ZOE removal or over fresh dentin (control), self-etching Adper SE Plus was applied immediately, after a 7- or 14-day delay. The cavity was restored with non-eugenol provisional material during this delay period. Cylinders of resin cement were built-up over the hybridized dentin. A shear load was applied to the cylinders at a crosshead speed of 0.5 mm/minute until failure. The data were statistically analyzed using two-way ANOVA and Tukey's tests (α=0.05).
  
  
  RESULTS
  Using IRM as a provisional restoration for 24 hours followed by its removal and immediate adhesive application resulted in the lowest values of shear bond strength. There was no significant difference between the other experimental conditions.
  
  
  CONCLUSIONS
  The use of IRM for 24 hours adversely affected the shear bond strength of a self-etching adhesive to dentin. The recovery of the proper bond strength occurred one week after IRM removal.
authors.affiliation: Department of Dentistry, State University of Montes Claros, Minas Gerais, Brazil.
authors.forename: J P L
authors.initials: JP
authors.lastname: Silva
authors.forename: D M
authors.initials: DM
authors.lastname: Queiroz
authors.forename: L H
authors.initials: LH
authors.lastname: Azevedo
authors.forename: L C
authors.initials: LC
authors.lastname: Leal
authors.forename: J L
authors.initials: JL
authors.lastname: Rodrigues
authors.forename: A F
authors.initials: AF
authors.lastname: Lima
authors.forename: G M
authors.initials: GM
authors.lastname: Marchi
authors.forename: M
authors.initials: M
authors.lastname: Brito-Júnior
authors.forename: A L
authors.initials: AL
authors.lastname: Faria-e-Silva
mesh_terms: D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate; D001840:Dental Bonding; D017005:Dental Debonding; D003794:Dental Restoration, Temporary / Q000379:methods*; D003799:Dental Stress Analysis; D003804:Dentin; D017220:Dentin-Bonding Agents; D006801:Humans; D008768:Methylmethacrylates; D010755:Organophosphates; D019279:Resin Cements; D033081:Shear Strength; D018709:Statistics, Nonparametric; D013997:Time Factors; D015035:Zinc Oxide-Eugenol Cement
chemical_list: C489661:Adper Prompt Self-Etch; D017220:Dentin-Bonding Agents; D008768:Methylmethacrylates; D010755:Organophosphates; D019279:Resin Cements; D015035:Zinc Oxide-Eugenol Cement; D017438:Bisphenol A-Glycidyl Methacrylate; C031667:IRM cement