title: Effect of cyclic compressive loading on the bond strength of an adhesive system to dentin after collagen removal.
abstract: OBJECTIVE
  The objective of this study was to verify the effect of cyclic compressive loading on the shear bond strength of an adhesive system following collagen removal.
  
  
  METHODS
  Sixty bovine teeth were divided into 4 groups based on the adhesive procedure used: groups 1 and 2--etching with 35% phosphoric acid and application of the Single Bond adhesive system; groups 3 and 4--after etching, a 10% sodium hypochlorite solution was applied for 1 min before the application of the adhesive. In all the specimens, a Z100 resin cylinder was built up over the bond area. Groups 2 and 4 were submitted to 500,000 cycles with a load of 100 N.
  
  
  RESULTS
  The mean values for the shear bond test (MPa) were: group 1: 7.37 +/- 1.15; group 2: 5.72 +/- 1.66; group 3: 5.95 +/- 1.21; group 4: 3.66 +/- 1.12. There was no difference between groups 1 and 2 (p > 0.01). Between groups 1 and 3, 2 and 4, and 3 and 4 there was a significant difference (p < 0.01). The majority of the specimens demonstrated an adhesive failure.
  
  
  CONCLUSIONS
  The application of sodium hypochlorite on dentin decreased the values of shear bond strength, as did the load cycling in the group treated with sodium hypochlorite.
authors.affiliation: Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, São Paulo State University-UNESP, Brazil.
authors.forename: Paulo Henrique
authors.initials: PH
authors.lastname: dos Santos
authors.forename: Mário Alexandre Coelho
authors.initials: MA
authors.lastname: Sinhoreti
authors.forename: Simonides
authors.initials: S
authors.lastname: Consani
authors.forename: Lourenço Correr
authors.initials: LC
authors.lastname: Sobrinho
authors.forename: Gelson Luis
authors.initials: GL
authors.lastname: Adabo
authors.forename: Luis Geraldo
authors.initials: LG
authors.lastname: Vaz
mesh_terms: D000134:Acid Etching, Dental; D000818:Animals; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002417:Cattle; D003094:Collagen / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry*; D010756:Phosphoric Acids / Q000737:chemistry; D033081:Shear Strength; D012822:Silicon Dioxide / Q000737:chemistry; D012973:Sodium Hypochlorite / Q000737:chemistry; D013314:Stress, Mechanical; D015040:Zirconium / Q000737:chemistry
chemical_list: D003188:Composite Resins; D017220:Dentin-Bonding Agents; D016877:Oxidants; D010756:Phosphoric Acids; C083568:Z100 composite resin; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate; D012822:Silicon Dioxide; D003094:Collagen; D015040:Zirconium; D012973:Sodium Hypochlorite