Pagnano VO, Leal MB, Catirse ABCEB, Curylofo PA, Silva RF, Macedo AP. Effect of oxidation heat treatment with airborne-particle abrasion on the shear bond strength of ceramic to base metal alloys.
J Prosthet Dent 2021;
126:804.e1-804.e9. [PMID:
34654570 DOI:
10.1016/j.prosdent.2021.08.013]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 10/20/2022]
Abstract
STATEMENT OF PROBLEM
Oxidation heat treatment has been studied to increase the metal-ceramic bond strength. However, information about its use with cobalt-chromium (Co-Cr) alloys is lacking.
PURPOSE
The purpose of this study was to evaluate the effect of oxidation heat treatment and oxidation heat treatment with alumina airborne-particle abrasion on the metal-ceramic bond strength of Co-Cr alloys compared with that of nickel-chromium (Ni-Cr) alloys.
MATERIAL AND METHODS
In total, 165 metal cylinders (∅5×8 mm) made of 5 base metal alloys were obtained by casting: 2 Ni-Cr (Fit Cast-SB and Fit Cast-V) and 3 Co-Cr alloys (Keragen, StarLoy C, and Remanium 2001). The specimens were divided into groups (n=11): no treatment, oxidation heat treatment, and oxidation heat treatment with airborne-particle abrasion. Oxidation heat treatment was performed starting at 650 °C and rising to 980 °C. The airborne-particle abrasion was performed with 100-μm alumina (0.2-MPa pressure, 5 seconds). One specimen had the surface topography and composition evaluated by scanning electron microscopy and energy dispersive X-ray spectrometry. The feldspathic ceramic was applied to the base metal alloy specimens (n=10). Shear tests were performed to obtain the metal-ceramic bond strength (MPa). The failure modes were evaluated. Data were evaluated by 2-way ANOVA and the Tukey post hoc test, Pearson correlation, and Fisher exact tests (α=.05).
RESULTS
The group without treatment showed the highest roughness. The treatments increased oxygen and chromium levels and decreased nickel, molybdenum, and tungsten levels. Oxidation heat treatment provided an increase in metal-ceramic bond strength (P<.05) for base metal alloys with over 7% molybdenum (Fit Cast-SB, Fit Cast-V, and Remanium 2001). With oxidation heat treatment with airborne-particle abrasion, there was improvement only in Fit Cast-SB. No treatment was better for StarLoy C. A weak correlation was found between metal-ceramic bond strength and failure mode (ρ=.166; P=.043). The mixed failures were prevalent in Co-Cr alloys (P<.001) and oxidation heat treatment with airborne-particle abrasion (P=.008).
CONCLUSIONS
The oxidation heat treatment was only beneficial for base metal alloy with a molybdenum content of over 7%. Although the oxidation heat treatment with alumina airborne-particle abrasion was a better treatment for Fit Cast-SB, its use is not justified because it showed no difference for oxidation heat treatment and requires another step in the surface treatment.
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