Purpose: To evaluate and compare the effect of accelerated aging and coffee immersion on the microhardness and gloss of a new computer-aided design and computer-aided manufacturing (CAD/CAM) hybrid material (Crystal Ultra) to those of contemporary restorative materials.
Materials and methods: A total of 160 specimens (12 × 14 × 1 mm ± 0.05 mm) were obtained from IPS e.max (IPS), VITA Enamic (VE), Crystal Ultra (CU), Lava Ultimate (LU), and CeraSmart (CS) high-translucency CAD/CAM blocks. The Vickers microhardness and gloss of the specimens were determined after thermocycling and coffee immersion. Data analysis was performed using SPSS (α = .05).
Results: IPS and CS specimens exhibited the highest (572.66 ± 11.30) and lowest (61.92 ± 3.91) microhardness, respectively. The highest gloss was observed with IPS specimens (3.31 ± 0.32), and LU specimens showed the lowest gloss (2.33 ± 0.06). A significant difference in gloss was observed between the materials at all measurement intervals (P < .01), except at T0 (P = .43). IPS specimens showed no significant changes in either group at any measurement interval.
Conclusions: The microhardness and gloss of the new CU material were comparable to those of the tested contemporary hybrid restorative materials. Glass-ceramic showed superior hardness and gloss compared to hybrid restorative materials. Accelerated aging with thermocycling and staining significantly affected the microhardness and gloss of all tested CAD/CAM materials.