Fracture toughness of high alumina core dental ceramics: the effect of water and artificial saliva
Mante, F.K.; Brantley, W.A.; Dhuru, V.B.; Ziebert, G.J.
International Journal of Prosthodontics 6(6): 546-552
1993
ISSN/ISBN: 0893-2174 PMID: 8148025 Document Number: 406398
The fracture toughnesses of two high alumina core ceramics were determined by using the single edge notched specimen method. Measurements were made in air, water, and artificial saliva. Fracture toughnesses of 1.89 and 1.75 MPa.m1/2 were obtained for Cerestore and Vitadur N samples, respectively, tested in air. Values obtained from Vitadur N samples that were tested in deionized water were significantly lower than those that were measured in air. Values for samples of both ceramics that were tested in artificial saliva were not significantly different from those that were tested in air. The fracture mode was a combination of intergranular and transgranular for Cerestore and predominantly transgranular for Vitadur N.