title: Effect of water storage on bond strength of self-adhesive resin cements to zirconium oxide ceramic.
abstract: OBJECTIVE
  To evaluate the microshear bond strength of resin cements to yttrium-stabilized tetragonal zirconium oxide surfaces after water storage for 24 h or 1 year.
  
  
  METHODS
  Four self-adhesive (BisCem, G-Cem, RelyX Unicem, SeT) and one conventional resin cement (RelyX ARC) were tested. The materials were mixed and inserted in tubes (0.75 mm diameter × 1 mm height) that were placed over the zirconium oxide surface. Specimens were tested after 24-h or 1-year water storage. Microshear testing was performed using a universal testing machine. Shear bond strength results were analyzed using two-way ANOVA and Tukey's test (5%).
  
  
  RESULTS
  After 24-h water storage, no difference was found between G-Cem and RelyX Unicem resin cements; however, their bond strength means to zirconium oxide were statistically higher than RelyX ARC. The bond strength values of all resin cements dropped significantly after 1 year of water storage. G-Cem presented the highest values among cements after long-term water exposure.
  
  
  CONCLUSIONS
  One-year water storage decreased the microshear bond strengths to zirconium oxide for all resin cements tested.
authors.affiliation: Department of Dentistry, State University of Amazonas, Manaus, Brazil.
authors.forename: Wladimir Franco
authors.initials: WF
authors.lastname: de Sá Barbosa
authors.forename: Thaiane Rodrigues
authors.initials: TR
authors.lastname: Aguiar
authors.forename: Marina Di
authors.initials: MD
authors.lastname: Francescantonio
authors.forename: Andrea Nóbrega
authors.initials: AN
authors.lastname: Cavalcanti
authors.forename: Marcelo Tavares
authors.initials: MT
authors.lastname: de Oliveira
authors.forename: Marcelo
authors.initials: M
authors.lastname: Giannini
mesh_terms: D001840:Dental Bonding; D003776:Dental Porcelain; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D004356:Drug Storage; D008422:Materials Testing; D019279:Resin Cements / Q000737:chemistry; D033081:Shear Strength; D014867:Water; D015019:Yttrium; D015040:Zirconium
chemical_list: D019279:Resin Cements; C499362:yttria stabilized tetragonal zirconia; D014867:Water; D003776:Dental Porcelain; D015019:Yttrium; D015040:Zirconium