title: A critical evaluation of bond strength tests for the assessment of bonding to Y-TZP.
abstract: OBJECTIVE
  To compare three different designs for measuring the bond strength between Y-TZP ceramic and a composite material, before and after ceramic surface treatment, evaluating the influence of the size of the adhesive interface for each design.
  
  
  METHODS
  'Macro' tensile, microtensile, 'macro' shear, microshear, 'macro' push-out, and micropush-out tests were carried out. Two Y-TZP surface treatments were evaluated: silanization (sil) and tribochemical silica coating (30μm silica-modified Al2O3 particles+silanization) (TBS). Failure mode analysis of tested samples was also performed.
  
  
  RESULTS
  Both the surface treatment and the size of the bonded interface significantly affected the results (p=0.00). Regardless of the type of surface treatment, the microtensile and microshear tests had higher values than their equivalent "macro" tests. However, the push-out test showed the highest values for the "macro" test. The tensile tests showed the greatest variability in results. The tribochemical silica coating method significantly increased bond strength for all tests.
  
  
  CONCLUSIONS
  Different test designs can change the outcome for Y-TZP/cement interfaces, in terms of mean values and reliability (variability). The 'micro' tests expressed higher bond strengths than their equivalent 'macro' tests, with the exception of the push-out test (macro>micro).
authors: Prosthodontics Unit, Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Brazil.
authors: Aline
authors: A
authors: Otani
authors: Science and Technology Institute, São Jose dos Campos Dental School, São Paulo State University, Brazil.
authors: Marina
authors: M
authors: Amaral
authors: Prosthodontics Unit, Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Brazil.
authors: Liliana G
authors: LG
authors: May
authors: Department of Biomaterials and Oral Biology, University of Sao Paulo, Sao Paulo, Brazil.
authors: Paulo F
authors: PF
authors: Cesar
authors: Prosthodontics Unit, Faculty of Odontology, Federal University of Santa Maria, Santa Maria, Brazil; Science and Technology Institute, São Jose dos Campos Dental School, São Paulo State University, Brazil. Electronic address: lfvalandro@hotmail.com.
authors: Luiz Felipe
authors: LF
authors: Valandro
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003776:Dental Porcelain / Q000737:chemistry; D003799:Dental Stress Analysis; D066298:In Vitro Techniques; D008422:Materials Testing; D015203:Reproducibility of Results; D019279:Resin Cements; D033081:Shear Strength; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties; D013718:Tensile Strength; D015019:Yttrium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D003188:Composite Resins; C000613954:Opallis; C528569:Rely-X; D019279:Resin Cements; D012821:Silanes; C499362:yttria stabilized tetragonal zirconia; D003776:Dental Porcelain; C070870:In-Ceram; D015019:Yttrium; D012822:Silicon Dioxide; D015040:Zirconium; D000537:Aluminum Oxide
keywords: Adhesion; Ceramics; Mechanical test; Reliability; Resin cement; Silica coating; Weibull analysis; Y-TZP