IADR Abstract Archives
Wear and Surface Hardness of Composite Blocks for CAD/CAM System
Objectives: The purpose of this study was to evaluate the surface hardness and 3-body wear resistance of various dental composite blocks for CAD/CAM system.
Methods: Five brands of composite resin blocks (Block HC, SHOFU; Cerasmart, GC; KZR-CAD HR, YAMAKIN; Lava Ultimate, 3M ESPE; MAZIC Duro, VERICOM) and one composite ceramic block (VITA Enamic, VITAta) for CAD/CAM system were tested. Wear was simulated with an OHSU oral wear simulator, which simultaneously incorporates the wear mechanism of attrition and abrasion in three-body wear mode. Composite block specimens were subjected to 50,000 cycles of wear against a steatite antagonist. Mixture of poppy seeds (2 g) and PMMA beads (1 g) in DW (10 ml) was used for 3-body abrasive medium. After wear simulation, average wear depths for abrasion wear and attrition wear were measured with the use of a 3D profilometer. Surface hardness of specimens was also evaluated using Vickers hardness tester. Ten specimens were tested each group.
Results: All composite blocks showed low abrasion wear (1.85-3.53 um). Cerasmart and MAZIC Duro showed the lower attrition wear (6.85 um and 6.67 um respectively) than others, and there were no significantly difference in attrition wear (12.34-15.25 um) for the other four composite blocks (p>0.05). Although, surface hardness of composite ceramic block (220 VHN) was two times larger than the composite resin blocks (66.5-93.2 VHN), composite ceramic block (VITA Enamic) showed the similar wear behavior to composite resin blocks. There was no correlation between surface hardness and wear resistance of composite blocks.
Conclusions: All composite blocks for CAD/CAM system showed the excellent wear resistance, they can be recommended for clinical application in the posterior region.
Methods: Five brands of composite resin blocks (Block HC, SHOFU; Cerasmart, GC; KZR-CAD HR, YAMAKIN; Lava Ultimate, 3M ESPE; MAZIC Duro, VERICOM) and one composite ceramic block (VITA Enamic, VITAta) for CAD/CAM system were tested. Wear was simulated with an OHSU oral wear simulator, which simultaneously incorporates the wear mechanism of attrition and abrasion in three-body wear mode. Composite block specimens were subjected to 50,000 cycles of wear against a steatite antagonist. Mixture of poppy seeds (2 g) and PMMA beads (1 g) in DW (10 ml) was used for 3-body abrasive medium. After wear simulation, average wear depths for abrasion wear and attrition wear were measured with the use of a 3D profilometer. Surface hardness of specimens was also evaluated using Vickers hardness tester. Ten specimens were tested each group.
Results: All composite blocks showed low abrasion wear (1.85-3.53 um). Cerasmart and MAZIC Duro showed the lower attrition wear (6.85 um and 6.67 um respectively) than others, and there were no significantly difference in attrition wear (12.34-15.25 um) for the other four composite blocks (p>0.05). Although, surface hardness of composite ceramic block (220 VHN) was two times larger than the composite resin blocks (66.5-93.2 VHN), composite ceramic block (VITA Enamic) showed the similar wear behavior to composite resin blocks. There was no correlation between surface hardness and wear resistance of composite blocks.
Conclusions: All composite blocks for CAD/CAM system showed the excellent wear resistance, they can be recommended for clinical application in the posterior region.