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 o C. The castings were divested manually and airborne-particle abraded with 100-mm 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 (a=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

Simplified Acid Treatment Technique in Cobalt-Chromium Alloys: Effect on Metal-Ceramic Bond Strength

“…The sample size for the metal-ceramic bond strength was based on the study of Farzin et al 29 , that showed a minimally significant difference of 8.23 and a standard deviation of 6.02, which led to n = 9/group to ensure a power of 80% (α = 0.05; β = 0.2). However, the sample size was increased to 10, consistent with that of previous study by the research group 30 .…”

Effect of different air-abrasion particles on metal-ceramic bond strength

“…Some authors stated that there is no methodology capable of measuring only shear forces along the metal-porcelain interface. 2,20,21 Hammad and Talic 20 carried out a critical analysis of tests used for metal-ceramic systems. These authors stated that shear tests with a flat interface mostly direct the tension to the interface and does not evaluate the elasticity modulus of the metal as in flexural tests.…”

Influência do tratamento ácido em infraestruturas de ligas metálicas de cobalto-cromo, sobre a resistência da união metalocerâmica

“…A utilização do berílio em ligas de Ni-Cr, outrora muito empregado por favorecer a fusibilidade dessas ligas e aumentar a resistência de união metalocerâmica (MACKERT; PARRY; FAIRHURST, 1986;BEZZON et al, 1998) foi questionada, principalmente por sua presença predispor a liga metálica à maior corrosão em meio bucal (WATAHA; MESSER, 2004). Além disso, outros estudos comprovaram que a adição desse elemento químico às ligas odontológicas não aumenta a resistência de união metalocerâmica (BEZZON et al, 2001;PAGNANO et al, 2009).…”