Color Stability of Glass Ionomer Cement (GIC) Modified with Silica from Beach Sand after Immersion in Arabica Gayo Coffee

Abstract

The discoloration is a condition that can affect the color stability of a material. The discoloration of glass ionomer cement (GIC) can occur due to extrinsic and intrinsic factors. GIC has poor mechanical properties, which are brittle, which shows high microporosity in GIC. Microporosity of GIC can affect the ability of materials in maintaining color stability. Therefore, it is necessary to add material alternatives to improve the mechanical properties in order to maintain color stability in GIC, such as silica. This study aims to determine the color change in GIC which is added with 5% silica after immersion in gayo arabica packaging coffee. Cylindrical specimens with a diameter of 5 mm and 2 mm thick. Specimens amounted to 16 pieces consisting of two treatment groups, the first group using conventional GIC and the second group using GIC with the addition of silica. Both groups were immersed in arabica gayo coffee for 4 days. Color changes were observed with a stereomicroscope and then the value of CIELab was used using Adobe Photoshop, which measured its average color change parameter (ΔE). The average value of discoloration of conventional GIC ΔE = 5.77 and GIC with the silica addition ΔE = 7.94. The results of the unpaired t-test show a value (p> 0.05) which means that there is a significant color change. It can be concluded that the two groups had discoloration after immersion in Arabica gayo coffee, and the color change value in conventional GIC with the addition of silica was higher than conventional GIC.