title: Tensile bond strength of filled and unfilled adhesives to dentin.
abstract: OBJECTIVE
  To determine the tensile bond strength of three filled and two unfilled adhesives applied to bovine dentin.
  
  
  METHODS
  Fragments of the labial dentin of bovine incisors were embedded in PVC cylinders with self-cure acrylic resin, and ground flat using 200 grit and 600 grit sandpaper. The following adhesive systems were tested (n=10): Prime & Bond NT, Prime & Bond NT dual cure, Prime & Bond 2.1, OptiBond Solo and Single Bond. A 3 mm-diameter bonding surface was delimited using a perforated adhesive tape. After etching with 37% phosphoric acid and adhesive application, a resin-based composite truncated cone (TPH, shade A3) was built. Tensile test was performed after 24 hrs storage in distilled water at 37 degrees C. Failure mode was accessed using a x10 magnification stereomicroscope.
  
  
  RESULTS
  Weibull statistical analysis revealed significant differences in the characteristic strength between Single Bond and Prime & Bond NT dual cure, and between Single Bond and Prime & Bond 2.1. The Weibull parameter (m) was statistically similar among the five groups. Single Bond and Prime & Bond NT showed areas of dentin cohesive failure in most of the specimens. For OptiBond Solo, Prime & Bond NT dual cure and Prime & Bond 2.1 failure was predominantly adhesive.
authors.affiliation: Department of Dental Materials, University of São Paulo, SP, Brazil. rrbraga@siso.fo.usp.br
authors.forename: R R
authors.initials: RR
authors.lastname: Braga
authors.forename: P F
authors.initials: PF
authors.lastname: Cesar
authors.forename: C C
authors.initials: CC
authors.lastname: Gonzaga
mesh_terms: D000134:Acid Etching, Dental; D000268:Adhesiveness; D000818:Animals; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry; D016001:Confidence Intervals; D001840:Dental Bonding; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry* / Q000145:classification; D010756:Phosphoric Acids / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D013223:Statistics as Topic; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D003188:Composite Resins; D017220:Dentin-Bonding Agents; C092987:Optibond; D010756:Phosphoric Acids; D011109:Polymethacrylic Acids; C103500:Prime & Bond; C425843:Prime and Bond NT; D019279:Resin Cements; C113300:TPH hybrid; C115612:single bond; D014867:Water; D017438:Bisphenol A-Glycidyl Methacrylate