IADR Abstract Archives
High Strength Hybrid-Ceramic for CAD/CAM Milling: a 3-Point Bending Test
Objectives: To compare mechanical characteristic (Flexural strength, Weibull modulus, Weibull characteristic strength and Elastic modulus) of different hybrid-ceramic blocks for CAD/CAM milling.
Methods: CAD-CAM blocks of Lava Ultimate (3M), Cerasmart (GC), Cerasmart 270 (GC) and Cerasmart 300 (GC) were cut with water cooled slow speed diamond saw in bars shape. A custom support was used to perpendicularly cut the blocks. Specimens were polished and finished with silica carbide papers of increasing grit. Final dimensions of the specimens were 2.0x2.0x16mm. Specimens were tested using a universal testing machine for the 3-point bending test. Flexural strength (s), Weibull modulus (m), Weibull characteristic strength (s0) and elastic modulus (E) were calculated. s and E data were statistically analyzed by two separate one-way ANOVA followed by Tukey test for post-hoc evaluation. The significance was set at p=0.05.
Results: The main flexural strength resulted in following order: Cerasmart 300a (302±32MPa), Cerasmart 270b (269±22MPa), Cerasmartc (238±20MPa) and Lava Ultimated (191±26MPa). The main Elastic Modulus resulted in the following order: Lava Ultimatea (13.40±0.96GPa), Cerasmarta (11.84±2.14GPa), Cerasmart 270ab (11.60±1.30GPa), Cerasmartb (10,02±2.24GPa). The Weibull modulus resulted to be always higher than 10 for the GC materials and 8.56 for 3M lava Ultimate.
Conclusions: The tested hybrid ceramic CAD/CAM blocks shown statistically significant different mechanical behaviors. Flexural Strength and Elastic modulus result in an inverse relation. The material selection should take into account that hybrid-ceramics demonstrate different characteristic and these could be a pivotal factor in the prognosis of CAD/CAM single restorations.
Methods: CAD-CAM blocks of Lava Ultimate (3M), Cerasmart (GC), Cerasmart 270 (GC) and Cerasmart 300 (GC) were cut with water cooled slow speed diamond saw in bars shape. A custom support was used to perpendicularly cut the blocks. Specimens were polished and finished with silica carbide papers of increasing grit. Final dimensions of the specimens were 2.0x2.0x16mm. Specimens were tested using a universal testing machine for the 3-point bending test. Flexural strength (s), Weibull modulus (m), Weibull characteristic strength (s0) and elastic modulus (E) were calculated. s and E data were statistically analyzed by two separate one-way ANOVA followed by Tukey test for post-hoc evaluation. The significance was set at p=0.05.
Results: The main flexural strength resulted in following order: Cerasmart 300a (302±32MPa), Cerasmart 270b (269±22MPa), Cerasmartc (238±20MPa) and Lava Ultimated (191±26MPa). The main Elastic Modulus resulted in the following order: Lava Ultimatea (13.40±0.96GPa), Cerasmarta (11.84±2.14GPa), Cerasmart 270ab (11.60±1.30GPa), Cerasmartb (10,02±2.24GPa). The Weibull modulus resulted to be always higher than 10 for the GC materials and 8.56 for 3M lava Ultimate.
Conclusions: The tested hybrid ceramic CAD/CAM blocks shown statistically significant different mechanical behaviors. Flexural Strength and Elastic modulus result in an inverse relation. The material selection should take into account that hybrid-ceramics demonstrate different characteristic and these could be a pivotal factor in the prognosis of CAD/CAM single restorations.