Effects of disinfection with a vinegar-hydrogen peroxide mixture on the surface composition and topography of a cobalt-chromium alloy

• Published in: The Journal of prosthetic dentistry
• Main Authors: Sakis, Gabriela Silveira, Kapczinski, Myriam Pereira, Fraga, Sara, Mengatto, Cristiane Machado
• Format: Journal Article
• Language: English
• Published: United States 19.12.2022
• ISSN: 1097-6841

Choosing the best disinfection agent for removable partial dentures may be challenging since most commercially available disinfection solutions alter the properties of the metal framework. The purpose of this in vitro study was to analyze the changes in the surface topography and elemental composition of a cobalt-chromium (Co-Cr) alloy when immersed in a vinegar-hydrogen peroxide mixture. Disk-shaped specimens (N=50) were fabricated with Co-Cr alloy and randomly distributed into 5 groups (N=10) according to the immersion solutions: distilled water (control) (W); 0.5% sodium hypochlorite (H); 3% hydrogen peroxide and water in a 1:1 ratio (HP); vinegar and water in a 1:1 ratio (V); and vinegar and 3% hydrogen peroxide mixture in a 1:1 ratio (VHP). The immersions simulated 90 uses of 10 minutes each. The surface topography and the elemental composition were analyzed with scanning electron microscopy and energy-dispersive spectroscopy, before (T ) and after (T ) the immersions. The 2-way ANOVA for repeated measures was used for statistical comparisons (α=.05). The tested mixture (VHP) did not change the metal surface topography or increase the oxygen proportion, indicating that no corrosion occurred. Similarly, groups W, HP, and V had no topographic changes and nonsignificant statistical differences at T for elemental composition (P>.05). However, the specimens immersed in sodium hypochlorite (H) showed staining, surface irregularity, composition change, with an appearance of 22.56% more oxygen, 41% less chromium, and 28.77% less cobalt at T (P<.05). The immersion of Co-Cr alloy in a vinegar-hydrogen peroxide mixture did not change the surface structure of the metal.