The fracture and fatigue of surface-treated tetragonal zirconia (Y-TZP) dental ceramics
Prelom in utrujenost površinsko obdelane tetragonalne (Y-TZP) dentalne keramike

english
slovenian

2007

volume 41, issue 5

Inštitut za kovinske materiale in tehnologije
(Obvezni izvod spletne publikacije)

The effects of dental grinding and sandblasting on the biaxial flexural strength of Y-TZP ceramics containing the mass fraction of 3 % yttria were evaluated. Dental grinding at high rotation speed lowers the mean strength under static loading and the survival rate under cyclic loading. Sandblasting, in contrast, may provide a powerful tool for surface strengthening also resulting in a substantially higher survival rate under cyclic loading. Fractographic examination of ground specimens revealed that failure originated from radial cracks extending up to 50 m from the grinding groves into the bulk of the material. However, no evidence of grinding-induced surface cracks could be obtained by SEM analysis of the ground samples, prepared by a standard bonded-interface technique. Sandblasting, in contrast, introduces lateral cracks, which are not detrimental to the strength of Y-TZP ceramics. The "medical-grade" Y-TZP ceramics also containing 0.25 % of dispersed alumina used in this work exhibited full stability under hydrothermal conditions.

08.06.2010