Objective The improvement of the optical properties of new generation dental ceramics enables more esthetic and durable restorations. This study aimed to investigate the color changes, caused by exposure to different beverages on composite, hybrid ceramic, and zirconia‐reinforced lithium silicate (ZLS) CAD/CAM blocks. Materials and methods CAD/CAM blocks 40 samples (1.5 × 7 × 12 mm) were obtained from each material under water cooling. Following the polishing process and the initial color measurement, the prepared samples were exposed to red wine, coffee, cola, energy drink, and distilled water. Color changes were measured by spectrophotometer at the end of the 1st, 7th, and 30th days. To analyze the color change results, one‐way analysis of variance (ANOVA) test was performed. Results In all restorative material groups, the most prominent color changes were observed on the red wine‐exposed samples, then the coffee‐exposed ones. No significant discoloration was observed on the samples exposed to cola and energy drink, compared to the control group (P > .05). Among the samples exposed to red wine and coffee, the highest discoloration values were observed in composite CAD/CAM material. Conclusions At the end of the 30th day, all materials exposed to wine and coffee showed color change above the clinically acceptable value (ΔE00:2.25). Clinical significance Hybrid ceramic and ZLS CAD/CAM blocks recently used more often by clinicians have shown similar color changes. The results of our study indicate the necessity of choosing esthetic materials according to the dietary habits of individuals.

Aim: Although it has been stated that composite resins should be used in the restoration of teeth after color shade selection, it has recently been stated that single-shade composite resins can be used for all tooth shades. The objective of our study is to evaluate the surface roughness and color change of single-shade composite resins compared with multi-shade system composite resins. Material and methods: In our study, samples (8 mm diameter and 2 mm depth) were obtained using single-shade (Omnichrorma) and multi-shade system (Filtek Universal Restorative, Clearfil Majesty ES-2 Premium, Harmonize) composite resins. Two steps finishing and polishing system (Clearfil Twist Dia) was used in the finishing polishing processes of the samples. The initial roughness values of the samples were measured with a profilometer and color values with a spectrophotometer. Then, color measurements of the samples kept in coffee were made on the 1 st , 7 th and 30 th days and after the last polishing process. The surface roughness (Ra) and color change (ΔE00) were statistically analyzed using two-way variance analysis (ANOVA) and Tukey post-hoc test (p<0.05). Results: There was no statistically significant difference between the initial surface roughness values of composite resins with single and multi-shade systems (p>0.05). Composite resin with single-shade system showed statistically significantly more color change than composite resin with multi-shade systems in all time periods (p<0.001). Although re-polishing these materials reduced the color changes, it could not decrease it below the acceptability threshold value (ΔE00:1.8). Conclusion: New generation single-shade composite resin with smart chromatic material technology can simplify color selection without sacrificing esthetic success. However, this composite resin shows more color changes than multi-shade systems composite resins.

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Introduction Some colorant foods and beverages cause undesired discoloration on dental restorations. The aim of this study was to investigate the effect of whitening kinds of toothpaste with different active ingredients on the color change of resin‐based CAD/CAM blocks. Material and methods In the study, resin‐based CAD/CAM block samples sized 1.5 × 7 × 12 mm, were prepared. Then, to simulate the time‐dependent color change, the samples were immersed in coffee (Nescafe Classic, Nestlé) for 14 days. After the color change values of the samples colored in coffee were measured by spectrophotometer, the samples were brushed with different types of whitening toothpastes for 4 minutes. Statistical analysis of the color change (ΔE00) was performed using the one‐way analysis of variance (ANOVA). Results Color differences occurring on all resin‐based CAD/CAM blocks immersed in coffee for 14 days exceeded the 50%:50% perceptibility threshold (PT) (ΔE00:0.8). There was no statistical significant difference between the whitening toothpastes containing activated charcoal, hydrogen peroxide (HP), blue covarine pigment, and microparticles in color improvement on resin‐based CAD/CAM blocks (P > .05). Conclusion It has been verified that the discoloration on resin‐based CAD/CAM blocks exhibiting color difference above the PT after coffee immersion can be reduced by utilizing toothpastes containing whiteners. Clinical significance Color changes that occur over time in resin‐based CAD/CAM blocks can be a clinical problem. These color changes in the materials can be reduced below the PT level using whitening toothpastes.

Purpose: This study investigated discoloration and surface roughness (Ra) of resin-based computer aided design (CAD)/computer aided manufacturing (CAM) blocks and direct and indirect resin composites after staining with coffee. Materials & Methods: Using a Teflon mold, 60 disc shaped specimens (8×2 mm2) were fabricated from direct (Estelite Asteria and GrandioSO) and indirect (Gradia Plus) resin composites, and 30 resin CAD/CAM specimens (12×14×2 mm3) were prepared from resin composite CAD/CAM blocks (Vita Enamic, Brilliant Crios, and Cerasmart) (n=10). A contact type profilometer was used to determine the Ra of all 60 polished samples. All specimens were thermocycled between 5 and 55°C for 3000 cycles, and immersed in coffee solution (37°C) for 1 and 7 days. A spectrophotometer was used to determine the color change (∆E00) with the CIEDE2000 formula after the specimens were re-polished. One-way analysis of variance (ANOVA) and Tukey multiple comparison test was performed to analyze the data (p<0.05). Results: The lowest degree of discoloration among the materials tested was found in Vita Enamic resin CAD/CAM block (p<0.001), whereas the highest degree of discoloration was found in the Gradia Plus indirect composite (p<0.001). There was no significant difference was seen between the initial surface roughness values (Ra) among the groups (p=0.249). No significant improvement was observed in the color of the groups except for the Cerasmart resin block after after polishing. Conclusion: Direct resin composites have a higher discoloration potential over resin-based CAD/CAM blocks, whereas they are less prone to discoloration than indirect resin composites

Objective: CAD/CAM blocks are widely used in dental restorations around the world. This study aimed to investigate the effects of different polishing and finishing systems on surface roughness and color change of resin-based CAD/CAM blocks. Material and Methods: In this study, material samples of 2×7×12mm were prepared. In three different experimental groups, surface polishing was carried out with one-step, two-step and multi-step polishing systems. The samples in one subgroup of each experimental group were polished with the diamond paste. Once the initial roughness and color values of the samples were measured using a profilometer and a spectrophotometer, the samples were immersed in coffee. Surface roughness and color change (∆E00) results were statistically analyzed using two-way variance analysis (ANOVA). Results: Finishing and polishing systems created significantly different levels of surface roughness on the hybrid ceramic block (Vita Enamic) but not on the composites block (Brilliant Crios, Grandio Blocs). While the two-step and multi-step finishing and polishing systems produced the lowest color change on hybrid ceramic blocks, one-step and two-step systems achieved this on composite blocks (p<0.05). In all test groups, the supplementary polishing performed after regular polishing procedures helped us reduce the surface roughness and color change on CAD/CAM blocks.  Conclusions: The findings obtained in this study suggest that one and two-step polishing systems are more suitable for resin-based composite CAD/CAM blocks; for hybrid ceramic CAD/CAM blocks, on the other hand, two and multi-step finishing and polishing systems seem to be more efficient concerning lower surface roughness and resistance to color changes.

Background High viscosity glass ionomer cement (HVGIC) and resin-modified glass ionomer cement (RMGIC) have recently been clinically preferred thanks to their numerous advantages. However, initial moisture contamination has a negative effect on the mechanical and physical properties of these cements. The aim of this study was in vitro of HVGICs and RMGICs, with and without surface protection, on water sorption, solubility and release of aluminum. Material and Methods In this study, as HVGICs; Equia Forte, IonoStar Plus, Riva Self Cure; as RMCIS, Ionolux and Riva Light Cure; and as control, Z250 universal composite was used. Equia coat, Voco varnish and Riva coat were chosen as surface protective. Water sorption and solubility levels of the samples were measured according to ISO 4049:2009. Al levels released from samples were determined by graphite furnace atomic absorption spectroscopy (GFAAS) for 7, 14 and 21 days. Statistical evaluation of the results was made using one-way variance analysis (ANOVA) and Tukey post-hoc test ( p <0.05). Results RMGICs from restorative materials showed more water absorption than HVGICs, but no differences in solubility. Among the materials tested, the water absorption values of the HVGIC and RMGIC materials without surface protection were higher than those with the surface protection ( p <0.001). Conclusions It was determined that the Al release of HVGIC and RMGIC groups with the surface protection were lower in all time periods than the groups without surface protection ( p <0.001). The application of surface protection effectively reduced water sorption and Al release from HVGICs and RMGICs. Key words: Highly viscous glass ionomer cement, resin coating, aluminum release, water sorption, solubility.

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