title: Shear bond strength between veneering ceramics and ceria-stabilized zirconia/alumina.
abstract: BACKGROUND
  Ceria-stabilized tetragonal ZrO(2)/Al(2)O(3) nanocomposite (Ce-TZP/A) offers superior properties compared to yttria-stabilized zirconia (Y-TZP). However, the bond quality to veneering ceramics has not been investigated.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the bond strength of different veneering ceramics to Ce-TZP/A.
  
  
  METHODS
  Cubes of Ce-TZP/A (NANOZR) (edge length, 10 mm) were layered with veneering ceramics (5 mm in thickness) with or without application of a liner and sheared at the interface. The effect of different surface treatments (polished with 3-mum diamond paste or airborne-particle abraded) was evaluated with 1 veneering ceramic (Cerabien ZR). Shear bond strength of 5 additional veneering ceramics (IPS e.max, Initial ZR, Triceram, Vintage ZR, or VITA VM 9) to polished Ce-TZP/A was measured (n=10). Polished Y-TZP (Hint-ELs ZrO(2) HIP) veneered with 2 ceramics (Cerabien ZR, Vintage ZR) served as the control. Mean shear bond strength values (MPa) were calculated. The means were statistically analyzed with 2-way ANOVA for the effect of surface treatment and liner, 2-way ANOVA for the effect of different veneering ceramic brands and liner, and 3-way ANOVA for the effect of substrate, veneering ceramic brands, and liner, as well as 1-way ANOVA for the differences between the veneering ceramics. A post hoc Scheffé test was used (alpha=.05).
  
  
  RESULTS
  The effects of surface treatment (P=.007) or application of liner (P<.001) were significant. Shear bond strength with different veneering ceramics showed bond strength values with means ranging between 14.2 +/-1.7 MPa (IPS e.max with liner) and 27.5 +/-4.2 MPa (VITA VM 9). A significant difference was found between the results of shear bond tests with Y-TZP and Ce-TZP/A (P=.022). The application of a liner on Y-TZP had no significant effect.
  
  
  CONCLUSIONS
  Airborne-particle abrasion is not necessary to enhance the shear bond strength of the evaluated veneering ceramics to Ce-TZP/A. Liners impair the shear bond strength of veneering ceramics to Ce-TZP/A.
authors.affiliation: Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, Center for Oral and Maxillofacial Medicine, University of Zurich, Zurich, Switzerland. jens.fischer@zzmk.uzh.ch <jens.fischer@zzmk.uzh.ch>
authors.forename: Jens
authors.initials: J
authors.lastname: Fischer
authors.forename: Bogna
authors.initials: B
authors.lastname: Stawarczyk
authors.forename: Irena
authors.initials: I
authors.lastname: Sailer
authors.forename: Christoph H F
authors.initials: CH
authors.lastname: Hämmerle
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D002563:Cerium / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods; D003764:Dental Materials / Q000737:chemistry*; D003775:Dental Polishing / Q000379:methods; D003776:Dental Porcelain / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D003801:Dental Veneers; D018130:Diamond / Q000737:chemistry; D006358:Hot Temperature; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites / Q000737:chemistry; D033081:Shear Strength; D013314:Stress, Mechanical; D013499:Surface Properties; D014618:Vacuum; D015019:Yttrium / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry*
chemical_list: C475766:Ce-TZP-Al2O3; D003188:Composite Resins; D003764:Dental Materials; C508050:IPS e.max Press; C096474:Vintage Porcelain; C499362:yttria stabilized tetragonal zirconia; D003776:Dental Porcelain; D002563:Cerium; D015019:Yttrium; D018130:Diamond; D015040:Zirconium; D000537:Aluminum Oxide; C028541:zirconium oxide