The aim of this research was to investigate the flexural strength and the Young’s modulus of three different machinable dental ceramics: zirconia Cercon (Degudent, Hanau, Germany), glassceramic IPS e.max CAD (Ivoclar Vivadent, Schaan, Liechtenstein), and polymerinfiltrated hybrid ceramic Enamic (VITA Zahnfabrik, Bad Säckingen, Germany). MATERIALS AND METHOD:A total of 15 samples of each material were prepared according to the ISO6872 standard. Three point bending tests were carried out on the specimens using a universal testing machine (Instron E3000) with a loading rate of 1 mm/min. The Weibull analysis was conducted on the experimental results and the Weibull distribution constants were recorded, i.e. Weibull modulus and the characteristic strength for 63.2% failure probability. The Young’s modulus was derived from the loaddisplacement curve of the samples from the flexural strength test data. RESULTS:The Weibull modulus of Cercon, IPS e.max CAD and Enamic were 12.12, 7.01, and 18.90; the respective characteristic strength of the materials were 934.39, 381.12, and 139.59 MPa; and the calculated Young’s modulus for the studied ceramics were found to be 91.79, 57.53, and 23.54 GPa. CONCLUSIONS:Enamic has a higher Weibull modulus which suggests that it has less scatter in its strength and is the most reliable material among others. However, its strength is the lowest. As Cercon is the stiffest (highest Young’s modulus) material with the highest strength, it could be an appropriate framework material for dental bridges. Enamic could be feasible as an indirect restorative material for premolars and IPS e.max CAD for molars.

Keywords