The aim of this study was to investigate the effect of post-polymerization time and curing device type on the surface roughness, microhardness and color change of 3D printed permanent resin materials. In this study, permanent resin samples with a layer print thickness of 50 μm and dimensions of 10 × 2 mm3 were produced on SLA and DLP printers. The samples were post-polymerized in blue LED and UV LED curing devices for 10, 20, 40 and 60 min. Initial surface roughness, microhardness and color values of all polymerized samples were measured. The samples were then aged (5000 cycles) and surface roughness, microhardness and color values were measured again. Data were evaluated using two-way analysis of variance (ANOVA) and Tukey post hoc test (p < 0.05). There was no statistically significant difference in surface roughness when the samples produced in SLA and DLP printer were polymerized using blue LED and UV LED curing device for different durations (p > 0.05). The samples produced in SLA printer showed higher microhardness value when polymerized with UV LED for longer time (p < 0.05). There was no statistically significant difference in the microhardness values of DLP samples when polymerized with blue LED and UV LED (p > 0.05). When the samples produced in SLA and DLP printer were polymerized using blue LED and UV LED curing device for different durations, the color change and whiteness index increased as the post-polymerization time increased (p < 0.05). The surface roughness of the samples after aging did not change statistically significantly, while the microhardness value decreased (p < 0.05). The post-polymerization time and the type of polymerization device do not affect the surface roughness of the 3D printed samples, but increase the microhardness value. Post-polymerization time increases the color change and whiteness index values of the samples. Post-polymerization of 3D printer permanent resin materials has an effect on the mechanical and optical properties of the material. The post polymerization time of 3D resin materials and the type of curing device change the microhardness, color change and surface roughness of the material. This may affect the clinical success of the restoration.

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.

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

The aim of this study was to investigate the surface roughness, gloss and microhardness values ​​of 3D-printed permanent resins after the use o