Comparative evaluation of mechanical properties and wear ability of five CAD/CAM dental blocks

This study compares the mechanical properties and wear ability of five CAD/CAM (computer-aided design/computer-aidedmanufacturing)millable dental blocks. All the discs, including Amber Mill Hybrid, Vita Enamic, Katana Avencia, Lava Ultimate, and Amber Mill, were cut in dimensions of 1.2mmin thickness and 12mmin diameter, polished to amachined surface, and immersed in distilled water for seven days. Vickers hardness was measured and the indentations were observed using microscope. The discs were brushed under a 150 g load. Mean surface roughness (Ra) and topography were determined after 100,000 cycles. Finally the biaxial flexure strength of the discs was measured and the broken surfaces were observed using scanning electron microscopy (SEM). The data was subjected toWeibull analysis. All data were analyzed by one-way analysis (ANOVA). The results of Vickers hardness are shown as: Amber Mill > Vita Enamic > Amber Mill Hybrid > Lava Ultimate > Katana Avencia. Katana Avencia showed the highest volume percentage reduction and the roughest surface after toothbrushing. The biaxial flexural strength is shown as: Amber Mill > Katana Avencia > Lava Ultimate > Amber Mill Hybrid > Vita Enamic. All the tested materials exhibited varying degrees of mass loss and surface roughness. The properties of the composite materials are related to the filler content, filler volume, and polymerization methods.