title: Adhesion to bovine dentin--surface characterization.
abstract: X-ray photo-electron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS) were used to characterize the dentin surface, to determine the effects of different pre-conditioning procedures on the elemental composition of the dentin surface, and to investigate the interaction between dentin and a dentin bonding agent (ScotchBond) by studying the changes in the elemental composition of dentin as a result of the interaction. Scanning electron microscopy (SEM) was used to characterize sample surface morphology, which was then correlated with surface elemental composition. The results showed that: (a) the elemental composition of the smear layer was similar to that of the underlying dentin; (b) cleaning with hydrogen-peroxide did not produce any modification in the elemental composition of the dentin surface; and (c) acid-etching led to an almost complete demineralization of the dentin, leaving behind an organic-rich surface. The results suggest that bonding systems that use acid-etching as a pre-conditioning procedure should be based on agents able to interact with the organic components of dentin, since bonding agents that rely on a chelation-to-calcium reaction are unlikely to be successful. The investigation of the interaction between the bonding agent and dentin led to a postulated adhesive-bonding reaction mechanism and suggested a partially cohesive failure in the bonding agent during fracturing of a dentin-bonding-agent-bonded assembly.
authors.affiliation: Centre for Biomaterials, Faculty of Dentistry, University of Toronto, Ontario, Canada.
authors.forename: N D
authors.initials: ND
authors.lastname: Ruse
authors.forename: D C
authors.initials: DC
authors.lastname: Smith
mesh_terms: D000134:Acid Etching, Dental; D000268:Adhesiveness; D000269:Adhesives / Q000737:chemistry; D000818:Animals; D002118:Calcium / Q000032:analysis; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding / Q000379:methods; D003738:Dental Cements / Q000737:chemistry; D003804:Dentin / Q000737:chemistry* / Q000187:drug effects / Q000648:ultrastructure; D017886:Durapatite; D006851:Hydrochloric Acid / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006882:Hydroxyapatites / Q000032:analysis; D013058:Mass Spectrometry; D008855:Microscopy, Electron, Scanning; D010756:Phosphoric Acids / Q000494:pharmacology; D019279:Resin Cements; D013052:Spectrometry, X-Ray Emission; D013314:Stress, Mechanical; D013499:Surface Properties
chemical_list: D000269:Adhesives; D003188:Composite Resins; D003738:Dental Cements; D006882:Hydroxyapatites; D010756:Phosphoric Acids; D019279:Resin Cements; C041330:Scotchbond; D017886:Durapatite; D006861:Hydrogen Peroxide; D006851:Hydrochloric Acid; D002118:Calcium