title: Micro-mechanical bond strength tests for the assessment of the adhesion of GIC to dentine.
abstract: BACKGROUND
  The aim of this study is to critically evaluate the bond strength (BS) of Glass-Ionomer Cements (GIC) to dentine with microtensile (μTBS) and microshear (μSBS) BS tests by assessing their rankings and failure patterns.
  
  
  METHODS
  Samples were made on flat dentine surfaces and submitted to μTBS and μSBS. The materials used were: high viscosity GIC (Ketac™ Molar Aplicap-KM), resin-modified GIC (Fuji II-FII), nano-filled resin-modified GIC (Ketac™ N100-N100) and an etch-and-rinse adhesive system with a composite resin (Adper™ Single Bond 2 and Z100™-Z100). All tests were performed with a Universal Testing Machine (24 h water storage, crosshead speed of 1 mm/min). Debonded surfaces were examined with a stereomicroscope (×40) to identify the failure mode. The data was analyzed with two-way ANOVA (p < 0.05) and LSD test.
  
  
  RESULTS
  Means were statistically different regarding the tests and materials, indicating that values for BS obtained for each material depend on the test performed. Failure analysis revealed that failures produced by μTBS were mainly cohesive for KM and FII. μSBS failures were mainly adhesive or mixed for all materials. For the μTBS, the rank was Z100 > FII > KM = N100, whereas for the μSBS it was Z100 = FII = KM > N100.
  
  
  CONCLUSIONS
  It may be concluded that distinct micro-mechanical tests present different failure patterns and rankings depending on the material to be considered.
authors.affiliation: Academic Centre of Dentistry Amsterdam, The Netherlands. c.bonifacio@acta.nl
authors.forename: Clarissa Calil
authors.initials: CC
authors.lastname: Bonifácio
authors.forename: Angela Mayumi
authors.initials: AM
authors.lastname: Shimaoka
authors.forename: Alessandra Pereira
authors.initials: AP
authors.lastname: de Andrade
authors.forename: Daniela Prócida
authors.initials: DP
authors.lastname: Raggio
authors.forename: Willem Evert
authors.initials: WE
authors.lastname: van Amerongen
authors.forename: Rubens Côrte Real
authors.initials: RC
authors.lastname: de Carvalho
mesh_terms: D001696:Biomechanical Phenomena; D003804:Dentin / Q000737:chemistry*; D005899:Glass Ionomer Cements / Q000737:chemistry*; D008422:Materials Testing; D012117:Resins, Synthetic / Q000737:chemistry*
chemical_list: D005899:Glass Ionomer Cements; D012117:Resins, Synthetic