IADR Abstract Archives
Wear, Strength, and Translucency of CAD/CAM Zirconia with Accelerated Sintering
Objectives: Zirconia blocks have been developed for chairside CAD/CAM fabrication that may be sintered in less than 30 minutes. The aim of this study was to compare the relevant properties of these zirconia materials to lithium disilicate.
Methods: Samples were prepared of 3 zirconia materials used for chairside CAD/CAM fabrication (3M Chairside Zirconia, Sirona Cerec Zirconia, Kuraray Katana STML) and lithium disilicate (Ivoclar e.max CAD LT), all shade A3. All zirconia specimens were fast sintered according to manufacturer IFU in a SpeedFire furnace. All specimens were polished to P2500 SiC paper. Wear of opposing enamel (n=8) was measured in the UAB wear testing device with standardized, conical, human molar antagonists. The wear test was performed with 20N/300,000cycles/33% glycerine lubricant. Volumetric enamel wear was measured with a non-contact profilometer. Three-point bend flexural strength specimens (16mmx4mmx1.2mm, n=10) were prepared and loaded to failure at 1mm/min. Translucency specimens were prepared (8.5mmx8.5mmx1mm, n=3). L*a*b* values were taken against white and black backgrounds with a Color-i7 spectrophotometer and deltaE was calculated to determine translucency parameter. Data were analyzed with ANOVA and Tukey post-hoc analyses.
Results: Results are presented in table 1 (mean+/-SD). There were significant differences between materials for all properties (p<.01). Materials in each column with different superscripts are statistically different.
Conclusions: All fast sintered zirconias demonstrated less opposing enamel wear, higher strength, and less translucency than lithium disilicate. 3M Chairside Zirconia and Cerec Zirconia demonstrated a higher strength than Kuraray Katana STML. For all other properties, there were no differences between brands of zirconia.
Methods: Samples were prepared of 3 zirconia materials used for chairside CAD/CAM fabrication (3M Chairside Zirconia, Sirona Cerec Zirconia, Kuraray Katana STML) and lithium disilicate (Ivoclar e.max CAD LT), all shade A3. All zirconia specimens were fast sintered according to manufacturer IFU in a SpeedFire furnace. All specimens were polished to P2500 SiC paper. Wear of opposing enamel (n=8) was measured in the UAB wear testing device with standardized, conical, human molar antagonists. The wear test was performed with 20N/300,000cycles/33% glycerine lubricant. Volumetric enamel wear was measured with a non-contact profilometer. Three-point bend flexural strength specimens (16mmx4mmx1.2mm, n=10) were prepared and loaded to failure at 1mm/min. Translucency specimens were prepared (8.5mmx8.5mmx1mm, n=3). L*a*b* values were taken against white and black backgrounds with a Color-i7 spectrophotometer and deltaE was calculated to determine translucency parameter. Data were analyzed with ANOVA and Tukey post-hoc analyses.
Results: Results are presented in table 1 (mean+/-SD). There were significant differences between materials for all properties (p<.01). Materials in each column with different superscripts are statistically different.
Conclusions: All fast sintered zirconias demonstrated less opposing enamel wear, higher strength, and less translucency than lithium disilicate. 3M Chairside Zirconia and Cerec Zirconia demonstrated a higher strength than Kuraray Katana STML. For all other properties, there were no differences between brands of zirconia.