title: Dentin-composite bond strength measurement using the Brazilian disk test.
abstract: This study presents a variant of the Brazilian disk test (BDT) for assessing the bond strength between composite resins and dentin.
  
  
  
  Dentin-composite disks (ϕ 5mm×2mm) were prepared using either Z100 or Z250 (3M ESPE) in combination with one of three adhesives, Adper Easy Bond (EB), Adper Scotchbond Multi-Purpose (MP) and Adper Single Bond (SB), and tested under diametral compression. Acoustic emission (AE) and digital image correlation (DIC) were used to monitor debonding of the composite from the dentin ring. A finite element (FE) model was created to calculate the bond strengths using the failure loads. Fracture modes were examined by scanning electron microscopy (SEM).
  
  
  
  Most specimens fractured along the dentin-resin composite interface. DIC and AE confirmed interfacial debonding immediately before fracture of the dentin ring. Results showed that the mean bond strength with EB (14.9±1.9MPa) was significantly higher than with MP (13.2±2.4MPa) or SB (12.9±3.0MPa) (p<0.05); no significant difference was found between MP and SB (p>0.05). Z100 (14.5±2.3MPa) showed higher bond strength than Z250 (12.7±2.5MPa) (p<0.05). Majority of specimens (91.3%) showed an adhesive failure mode. EB failed mostly at the dentin-adhesive interface, whereas MP at the composite-adhesive interface; specimens with SB failed at the composite-adhesive interface and cohesively in the adhesive.
  
  
  
  The BDT variant showed to be a suitable alternative for measuring the bond strength between dentin and composite, with zero premature failure, reduced variability in the measurements, and consistent failure at the dentin-composite interface.
  
  
  
  The new test could help to predict the clinical performance of adhesive systems more effectively and consistently by reducing the coefficient of variation in the measured bond strength.
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Carola A
authors.initials: CA
authors.lastname: Carrera
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Yung-Chung
authors.initials: YC
authors.lastname: Chen
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Yuping
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Joel
authors.initials: J
authors.lastname: Rudney
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Conrado
authors.initials: C
authors.lastname: Aparicio
authors.affiliation: Minnesota Dental Research Center for Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, Minneapolis, MN, USA. Electronic address: alexfok@umn.edu.
authors.forename: Alex
authors.initials: A
authors.lastname: Fok
mesh_terms: D001938:Brazil; D003188:Composite Resins; D001840:Dental Bonding; D003804:Dentin; D017220:Dentin-Bonding Agents; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength
chemical_list: D003188:Composite Resins; D017220:Dentin-Bonding Agents; D019279:Resin Cements
keywords: Adhesive; Bond strength; Brazilian disk; Dentin; Resin composite