title: Effects of surface treatments and storage times on the tensile bond strength of adhesive cements to noble and base metal alloys.
abstract: This work evaluated two resin cements and a glass-ionomer cement and their bond strength to gold-palladium (Au-Pd), silver-palladium (Ag-Pd), and nickel-chromium-beryllium (Ni-Cr-Be) alloys, utilizing three surface treatments over a period of six months. Eight hundred ten pieces were cast (in a button shape flat surfaces) in one of three alloys. Each alloy group was assigned to three other groups, based on the surface treatment utilized. Specimens were fabricated by bonding similar buttons in using one of three adhesive cements. The 405 pairs were thermocycled and stored in saline solution (0.9% NaCl) at 37 degrees C. The tensile bond strengths were measured in a universal testing machine after storage times of 2, 90, or 180 days. The highest mean bond strength value was obtained with the base metal alloy (10.9 +/- 8.6 MPa). In terms of surface treatment, oxidation resulted in the highest mean bond strength (13.7 +/- 7.3 MPa), followed by sandblasting (10.3 +/- 5.5 MPa) and polishing (3.0 +/- 6.4 MPa). Panavia Ex (13.2 +/- 9.3 MPa) showed significantly higher bond strengths than the other two cements, although the storage time reduced all bond strengths significantly.
authors.affiliation: Department of Restorative Dentistry, Federal University of Santa Maria, RS, Brazil.
authors.forename: Paulo Afonso
authors.initials: PA
authors.lastname: Burmann
authors.forename: Jose Fortunato Ferreira
authors.initials: JF
authors.lastname: Santos
authors.forename: Liliana Gressler
authors.initials: LG
authors.lastname: May
authors.forename: Joao Eduardo da Silva
authors.initials: JE
authors.lastname: Pereira
authors.forename: Paulo Eduardo Capel
authors.initials: PE
authors.lastname: Cardoso
mesh_terms: D002484:Cementation; D003722:Dental Alloys / Q000737:chemistry*; D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods*; D003799:Dental Stress Analysis; D008670:Metals / Q000737:chemistry / Q000145:classification; D010084:Oxidation-Reduction; D019279:Resin Cements / Q000737:chemistry*; D013499:Surface Properties; D013718:Tensile Strength; D013997:Time Factors
chemical_list: D003722:Dental Alloys; D008670:Metals; D019279:Resin Cements