Adhesive bonding of alumina air-abraded Ag-Pd-Cu-Au alloy with 10-methacryloyloxydecyl dihydrogen phosphate.

The aim of this paper is to study changes in the Ag-Pd-Cu-Au alloy surfaces by alumina air-abrasion process and effect of those changes on the adhesive bonding characteristic. Surface roughness, surface composition and chemical state of the alumina air-abraded alloys were analyzed by a confocal laser scanning microscope, an energy dispersive X-ray spectroscopy and an X-ray photoelectron spectroscopy. The results showed that the alumina air-abrasion changed the alloy surface by mechanical roughening, alumina remain and copper oxidation. Effect of the changes in the alloy surface on the adhesive bonding characteristic was examined by using a methyl methacrylate/tri-n-butylborane derivative (MMA/TBB) resin cement with the 10-methacryloyloxydecyl dihydrogen phosphate (MDP) contained primer. The shear bond strength test results indicated that the surface oxidation by the abrasion is the main contributor that improved the adhesive bonding rather than other effects such as mechanical roughening or alumina remain.

Chemical alteration of Ag-Pd-Cu-Au alloy surface by alumina air-abrasion and its effect on bonding to resin cement.

The goal of this study was to investigate the chemical alteration of a dental alloy surface by alumina air-abrasion and its effect on bonding to resin cement. Alumina air-abrasion was carried out on an Ag-Pd-Cu-Au alloy. The surface morphology and chemical state of the abraded alloy were characterized. The effect of the air-abrasion on the shear bond strength between the alloy and a methyl methacrylate/tri-n-butyl borane (MMA/TBB) resin cement with some primers was evaluated. The surface characterization revealed that the alumina air-abrasion mechanically roughened and chemically altered the surface. The chemical alterations had two effects: (1) abraded alumina particles remained on the alloy surface and (2) copper ions were oxidized in the alloy surface. As the result, the shear bond strength test indicated that 10-methacryloyloxydecyl dihydrogen phosphate (MDP) contained primer worked with the abraded alloy surface, whereas it did not work with the non-abraded alloy surface.

Influence of atmospheric pressure low-temperature plasma treatment on the shear bond strength between zirconia and resin cement.

PURPOSE: Zirconia exhibits excellent strength and high biocompatibility in technological applications and it is has therefore been investigated for clinical applications and research. Before setting prostheses, a crown prosthesis inner surface is sandblasted with alumina to remove contaminants and form small cavities. This alumina sandblasting causes stress-induced phase transition of zirconia. Atmospheric-pressure low-temperature plasma has been applied in the dental industry, particularly for adhesives, as a surface treatment to activate the surface energy and remove contaminants. The purpose of this study was to examine the influence of atmospheric-pressure low-temperature plasma treatment on the shear bond strength between zirconia and adhesive resin cement. METHODS: The surface treatment method was classified into three groups: untreated (Cont group), alumina sandblast treatment (Sb group), and atmospheric-pressure low-temperature plasma treatment (Ps group). Adhesive resin cement was applied to stainless steel and bonded to zirconia. Shear adhesion tests were performed after complete hardening of the cement. Multiple comparisons were performed using a one-way analysis of variance and the Bonferroni method. X-ray diffractometry was used to examine the change in zirconia crystal structure. RESULTS: Statistically significant differences were noted between the control and Sb groups and between the control and Ps groups. In contrast, no statistically significant differences were noted for the Ps and Sb bond strength. Atmospheric-pressure low-temperature plasma treatment did not affect the zirconia crystal structure. CONCLUSIONS: Atmospheric-pressure low-temperature plasma treatment improves the bonding strength of adhesive resin cement as effectively as alumina sandblasting, and does not alter the zirconia crystal structure.