title: Effect of casting atmosphere on the shear bond strength of a ceramic to Ni-Cr and Ni-Cr-Be alloys.
abstract: The success of metal-ceramic restorations depends on an optimal bond between metal and ceramic. This study evaluated the effect of 3 casting atmospheres on the metal-ceramic bond strength (MCBS) of 2 Ni-Cr alloys, with beryllium (Fit Cast V) and without beryllium (Fit Cast SB). Sixty acrylic resin patterns (8 mm long and 5 mm diameter) were obtained using a fluorocarbon resin matrix. Wax was used to refine the surface of acrylic resin patterns that were invested and cast in an induction casting machine under normal, vacuum, and argon atmospheres at a temperature of 1340 degrees C. The castings were divested manually and airborne-particle abraded with 100-microm aluminum-oxide. Ten castings were obtained for each group. The IPS Classic V ceramic was applied (2 mm high and 5 mm diameter). The shear bond strength was tested in a mechanical testing machine with a crosshead speed of 2.0 mm/min. The MCBS data (MPa) were subjected to 2-way analysis of variance (alpha=0.05). There was no statistically significant difference (p>0.05) between the alloys or among the casting atmospheres. Within the limitations of this study, it may be concluded that the presence of beryllium and the casting atmosphere did not interfere in the MCBS of the evaluated metal-ceramic combinations.
authors.affiliation: Department of Dental Materials and Prosthodontics, Ribeirão Preto Dental School, University of São Paulo, Ribeirão Preto, SP, Brazil. valpag@forp.usp.br
authors.forename: Valéria Oliveira
authors.initials: VO
authors.lastname: Pagnano
authors.forename: Marina de Campos
authors.initials: Mde C
authors.lastname: Esquivel
authors.forename: Mônica Barbosa
authors.initials: MB
authors.lastname: Leal
authors.forename: Daniela Nair Borges
authors.initials: DN
authors.lastname: Felipucci
authors.forename: Osvaldo Luiz
authors.initials: OL
authors.lastname: Bezzon
mesh_terms: D001128:Argon; D001272:Atmosphere; D002858:Chromium Alloys; D001840:Dental Bonding; D003735:Dental Casting Technique; D003799:Dental Stress Analysis; D016876:Metal Ceramic Alloys; D009532:Nickel; D033081:Shear Strength; D014618:Vacuum
chemical_list: D002858:Chromium Alloys; D016876:Metal Ceramic Alloys; C403005:nickel-chromium-beryllium alloy; D001128:Argon; D009532:Nickel