Altered tissue contribution to interfacial bond strength with acid conditioned dentin.
OBJECTIVE
To measure the shear bond strength of resin composite to dentin using three fourth generation bonding agents in combination with three different acid treatments. One such treatment was followed by sodium hypochlorite. The purpose was to determine the contribution which the collagen rich, demineralized zone made to bond strength.


METHODS
Three groups, representing (1) All Bond 2/BisFil, (2) Optibond Dual Cure/XRV and (3) Scotchbond Multi-Purpose/Z100, contained four sub-groups each comprised of 10 caries-free molar teeth whose dentin was exposed in a transverse mid-coronal plane. Dressed with 320 grit, wet silicon carbide paper, the dentin surface in each sub-group was conditioned with 10% maleic acid (15 seconds), 10% phosphoric acid (20 seconds), 2.5% nitric acid (60 seconds) and 10% phosphoric acid (20 seconds) followed by 5% sodium hypochlorite (120 seconds). The bonded resin composite assemblies were stored in water at 37 degrees C for 24 hours and then subjected to shear force at a crosshead speed of 5 mm/minute until failure.


RESULTS
The mean and standard deviation values derived for the groups were not statistically different from each other (P < 0.05). It was concluded that the type of conditioning agent was not a factor in achieving optimal bond strength for the system tested. Furthermore, it was tentatively concluded that the collagen-rich zone offered no direct, quantitative contribution to the interfacial bond strength which is probably derived from complete resin diffusion into the porous, partially demineralized dentin below.
Gwinnett
A J
AJ
Department of Oral Biology/Pathology, State University of New York, Stony Brook.
D000134:Acid Etching, Dental / Q000379:methods; D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate; D003094:Collagen / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003804:Dentin / Q000187:drug effects / Q000648:ultrastructure; D003806:Dentin Permeability / Q000187:drug effects; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D008298:Maleates; D008422:Materials Testing; D008689:Methacrylates; D008855:Microscopy, Electron, Scanning; D017942:Nitric Acid; D010756:Phosphoric Acids; D019279:Resin Cements; D012822:Silicon Dioxide; D012973:Sodium Hypochlorite; D013499:Surface Properties / Q000187:drug effects; D013718:Tensile Strength; D015040:Zirconium
C074864:All-Bond system; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D008298:Maleates; D008689:Methacrylates; C088316:Optibond Dual Cure; D010756:Phosphoric Acids; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; C083568:Z100 composite resin; C078905:Bisfil; C065770:Herculite XR; D017942:Nitric Acid; D017438:Bisphenol A-Glycidyl Methacrylate; D012822:Silicon Dioxide; D003094:Collagen; C030272:maleic acid; D015040:Zirconium; D012973:Sodium Hypochlorite; C030242:phosphoric acid