Influence of staining beverages and surface finishing on color stability and surface roughness of all-ceramic restorations: Laboratory study

Purpose: Objectives of this study were to assess and compare the impact of coloring beverages and surface finishing on color stability and surface roughness of dental ceramics. Material and methods: Twenty-eight identical cuboids (14*12*1mm) were cut from zirconia-reinforced lithium silicate blocks (suprinity) using a precision cutting machine. Another 28 identical cuboids with the same dimensions were milled from high translucent zirconia ceramic blank (zolid fx). The specimens of each ceramic material were divided into 2 main groups (n=14) according to the finishing technique used; group G: specimens were glazed. group P: specimens were polished. Each subgroup was subdivided into 2 subgroups (n=7) according to the immersion solution used; Tea or Cola. Color measurements and surface roughness of all specimens were measured at the beginning and after 28 days of immersion in the staining beverages. Results: Tea possessed the highest color changes in all tested groups, and these changes were statistically significant compared with those of Cola in both surface finishing groups and in both types of ceramics. The color changes of Tea were not clinically acceptable in the zirconia ceramic groups (ΔE ˃3.3). While Cola possessed the highest mean Ra in all tested groups, and these changes were statistically significant compared with those of Tea in both surface finishing groups and in both types of ceramics. Conclusions: Tea showed the highest impact on the color of polished and glazed types of used ceramics, while Cola significantly increased the surface roughness of both polished and glazed types of used ceramics.