title: Effect of an experimental zirconia-silica coating technique on micro tensile bond strength of zirconia in different priming conditions.
abstract: OBJECTIVE
  This study aimed to evaluate the adhesive properties of a MDP-containing resin cement to a colored zirconia ceramic, using an experimental zirconia-silica coating technique with different priming conditions.
  
  
  METHODS
  18 zirconia ceramic discs (Cercon base colored) were divided into two groups: the control group and the experimental zirconia-silica coating group. Specimens in each group were further divided into 3 subgroups (n = 3) according to the priming conditions: no primer, a MDP-containing primer (ED Primer II) or a silane coupling primer (RelyX™ Ceramic Primer). Then resin-composite discs (Filtek™ Z250) were bonded to the treated surface using a MDP-containing resin cement (Panavia F 2.0). The bi-layered specimens were cut into microbars and 20 microbars were randomly selected from each specimen, half of which were stored in 37°C water bath for 24h, and the other half were stored for 30 days. After water storage, the samples were exposed to a micro tensile bond strength test (MTBS). The results were analyzed by ANOVA, while the fracture surfaces were examined by SEM.
  
  
  RESULTS
  After 24h water storage, zirconia-silica coating followed by silanization showed a significantly (P<0.001) higher MTBS value 45.0 (10.9)MPa. Water storage affected (P<0.05) MTBS in the control group (24.1-30.3 MPa to 2.8-3.1 MPa), but only partially in the zirconia-silica coating group (20.0-45.1 MPa to 17.4-25.9 MPa). SEM analysis revealed a failure mode change after water storage.
  
  
  CONCLUSIONS
  The combination of zirconia-silica coating with silane coupling can improve the bonding of resin cement to this colored zirconia.
authors.affiliation: Department of Dental Materials Science, ACTA, Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands. c.f.chen@acta.nl
authors.forename: Chenfeng
authors.initials: C
authors.lastname: Chen
authors.forename: Cornelis J
authors.initials: CJ
authors.lastname: Kleverlaan
authors.forename: Albert J
authors.initials: AJ
authors.lastname: Feilzer
mesh_terms: D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D003116:Color; D001840:Dental Bonding / Q000379:methods*; D045662:Dental Etching / Q000379:methods; D003776:Dental Porcelain; D003799:Dental Stress Analysis; D006358:Hot Temperature; D008422:Materials Testing; D008689:Methacrylates; D019279:Resin Cements; D012821:Silanes; D012822:Silicon Dioxide; D013499:Surface Properties; D013718:Tensile Strength; D015040:Zirconium
chemical_list: D020099:Coated Materials, Biocompatible; D008689:Methacrylates; D019279:Resin Cements; D012821:Silanes; D003776:Dental Porcelain; D012822:Silicon Dioxide; C069749:methacryloyloxydecyl dihydrogen phosphate; D015040:Zirconium; C028541:zirconium oxide