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Background: The aim of this study was to investigate the effect of an immune-boosting beverage with Sambucus nigra (SAM), an energy beverage (ENE), an in-office bleaching agent with a novel composition, and a fine-grain professional dental prophylaxis (PDP) paste on the surface roughness (Ra) and microhardness (MH) of CAD/CAM restorative materials over time. Methods: Feldspathic ceramic (FC) and polymer infiltrated ceramic network (PICN) specimens were prepared (N = 126). Glazing, polishing, bleaching and immersion in beverages groups were formed. Bleaching gel containing 25% Hydrogen Peroxide Superior was applied to the specimens with a bleaching pen. Ra and MH were measured at five time points of baseline, days 1, 14, 28 and after PDP. Scanning electron microscopy (SEM) images were taken after PDP. Statistics were performed by ANOVA and Bonferroni tests (α = 0.05). Results: Ra increased over time regardless of material type, polishing method, beverage type and bleaching (p < 0.0001). Glazed and polished FCs caused higher roughness than PICN, SAM and ENE than distilled water, and bleaching than no bleaching (p < 0.0001). For glazed or polished FCs, MH decreased slightly lower at all time points, but for PICN, MH increased until day 28, not changing after PDP. Beverages decreased the MH of ceramics at all time points, but PDP did not lead to a change for PICN (p < 0.0001). The MH decreased more in bleached specimens than in non-bleached specimens up to day 28 (p < 0.0001). According to the SEM images after PDP, the glazed FC had numerous crack marks, pores and detached particles. The polished FC had traces of mechanical polishing. The polymer part of the PICN had voids, but the ceramic part was better preserved. Conclusions: Both energy beverages and immune-boosting beverages can increase roughness on FCs compared to PICNs. There was no significant difference between glazing and polishing in terms of lower roughness in FCs. PDP tended to slightly increase the roughness for ceramics, while it tended not to change it for PICN. Beverages decreased the microhardness of ceramics. PDP further decreased the microhardness in glazed ceramics, but increased it in polished ones. In PICN the microhardness increased over time, but decreased slightly after PDP. [ABSTRACT FROM AUTHOR]

Background: The effect of an immune-boosting beverage (SAM) containing Sambucus Nigra, an energy beverage (ENE), an in-office bleaching (BLE) agent with 25% hydrogen peroxide superior, glazing (GLA) or polishing (POL) methods, and professional dental prophylaxis (PDP) on the color of CAD-CAM restorative materials is unknown. Methods: In total 210 specimens were prepared, consisting of CAD-CAM feldspathic (FC), zirconia-reinforced lithium disilicate ceramic (ZLS) and hybrid ceramic (HC). The ceramic specimens were divided according to the polishing methods of glazing (GLA) and mechanical polishing (POL). All materials were divided into two groups: with and without BLE. A 25% hydrogen peroxide superior (HPS) gel was used for BLE. After the baseline (BAS) measurement, the specimens were immersed in 3 different beverages (distilled water (DIS), SAM, ENE). After 28 days, a fine-grained (RDA 7) prophylaxis paste was applied. Statistical analysis of ∆E00 color difference values was performed by 3-way ANOVA and Bonferroni test (α = 0.05). Results: The effect of all other actions except material-BLE-beverage on color for BAS-Day 28 was statistically different (p < 0.05). The effect of material, material-BLE, beverage on color for Day 28-PDP was statistically different (p < 0.05). After 28 days, the lowest color change was found in FC-GLA and HC immersed in DIS (p = 0.0001) and the highest in FC-POL immersed in ENE (p = 0.0002). PDP was efficient in color recovery in HC immersed to DIS, ENE and SAM (p = 0.0010). For FC, HC and ZLS, BLE caused a higher color change (p < 0.0001). Regardless of the material, the highest color change for BLE-beverage was found in BLE-treated specimens immersed in ENE (p = 0.0496) and the lowest color change was found in non-BLE-treated specimens immersed in SAM (p = 0.0074). Conclusions: In materials pre-exposed to 25% HPS, the effect of PDP on color recovery was lower than in unexposed materials. After 28 days, mechanical polishing produced higher color change in FC than glazing, however, in ZLS effects of glazing and mechanical polishing on color were similar. For material/polishing method, HC was the most effective. ENE caused higher color change than DIS and SAM. PDP was more effective than ENE in restoring color to DIS- and SAM-immersed specimens. [ABSTRACT FROM AUTHOR]

PURPOSE. Surface color is one of the main criteria to obtain an ideal esthetic. Many factors such as the type of the material, surface specifications, number of firings, firing temperature and thickness of the porcelain are all important to provide an unchanged surface color in dental ceramics. The aim of this study was to evaluate the color changes in dental ceramics according to the material type and glazing methods, during the multiple firings. MATERIALS AND METHODS. Three different types of dental ceramics (IPS Classical metal ceramic, Empress Esthetic and Empress 2 ceramics) were used in the study. Porcelains were evaluated under five main groups according to glaze and natural glaze methods. Color changes (ΔE) and changes in color parameters (ΔL, Δa, Δb) were determined using colorimeter during the control, the first, third, fifth, and seventh firings. The statistical analysis of the results was performed using ANOVA and Tukey test. RESULTS. The color changes which occurred upon material-method-firing interaction were statistically significant (P<.05). ΔE, ΔL, Δa and Δb values also demonstrated a negative trend. The MC-G group was less affected in terms of color changes compared to other groups. In all-ceramic specimens, the surface color was significantly affected by multiple firings. CONCLUSION. Firing detrimentally affected the structure of the porcelain surface and hence caused fading of the color and prominence of yellow and red characters. Compressible all-ceramics were remarkably affected by repeated firings due to their crystalline structure. [ABSTRACT FROM AUTHOR]