Wear, Microhardness and Fracture Toughness of Different CAD/CAM Ceramics

Asaad, Rasha Sayed; Salem, Shereen

doi:10.21608/edj.2020.45103.1287

Wear, Microhardness and Fracture Toughness of Different CAD/CAM Ceramics

Document Type : Original Article

Authors

Rasha Sayed Asaad ¹
Shereen Salem ²

¹ Oral and Maxillofacial Prosthodontic Department, Faculty of Dentistry, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia.

² Associate Professor of Fixed Prosthodontics, Faculty of Dentistry, October 6 University, Giza, Egypt

10.21608/edj.2020.45103.1287

Abstract

Objective: To evaluate wear of three CAD/CAM ceramics (Lithium Disilicate, Zirconia reinforced-lithium silicate, Zirconia-based) and their opposing enamel antagonist in addition to their microhardness & fracture toughness.
Materials and Methods: Thirty rectangular shaped samples (12 x 14 x 2 mm)were fabricated and divided into three groups according to the type of ceramic used (10 samples each):Group(IP): IPS e.max CAD, Group(VS):Vita Suprinity and Group(BZ): BruxZir. Each group was divided into two sub-groups (5 samples each) according to the testing procedure. The first sub-groups were subjected to microhardness and fracture toughness tests, while the second sub-groups were first weighed then subjected to wear test and finally re-weighed again before being subjected to microhardness and fracture toughness tests.
Results: Wear results showed a significant difference in weight loss of tested ceramics and the antagonist tooth structure between (BZ) and both (IP) & (VS) . Microhardness of the three ceramics were significantly different in each sub-group regardless of wear test. Regarding fracture toughness, there was a significant difference between (BZ) and both (IP) & (VS) in both sub-groups. For all tested ceramics, both sub-groups (without wear and after wear) were not statistically significantly different regarding microhardness and fracture toughness.
Conclusions: BruxZir showed the best wear behavior and the worst abrasiveness to enamel. Microhardness and fracture toughness were the highest for zirconia-based ceramic but both parameters were not affected by thermo-mechanical aging of wear test for the three tested ceramics.

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