Color evaluation of esthetic brackets when subjected to staining challenge

Objectives: To evaluate the color of ceramic and polycarbonate brackets (monocrystalline and polycrystalline), when stored in water and red wine, directly and on daily immersions in red wine during different time intervals. Methods: polycarbonate (Composite), polycrystalline ceramic (Ceramic and Zetta) and monocrystalline ceramic (Maia): 4 different compositions and trademarks of brackets were selected. The initial color reading of the brackets was performed using a spectrophotometer in CIE L* a* b*, then the brackets were divided into groups (n = 10): the control group (immersed in distilled water), a group immersed in red wine and a bath group (immersed in distilled water and given daily baths of 15 minutes in red wine). Successive readings were performed in the period of 15 days, 30 days and 45 days. The color change (ΔE) was calculated using the ΔE = ((ΔL)2 + (Δa)2+ (Δb)2)1/2 formula. Data were tabulated and analyzed statistically. Results: There was a color change in all tested materials. The highest color change was found in the direct immersion in red wine, followed by the group that underwent daily showers, and the group in distilled water. Polycarbonate suffered greater color change in relation to ceramics, and polycrystalline ceramic suffered greater color change compared to monocrystalline ceramic. The longest times showed the greatest color changes. Conclusion: The type of material and the time of contact with the colorant directly influence the color stability of the brackets.