Microhardness and Gloss of a New CAD/CAM Hybrid Material Following Accelerated Aging and Coffee Immersion.

Abstract

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. 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). 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. 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.