The strength and hydrothermal stability of Y-TZP ceramics for dental applications

Effects of dental grinding, sandblasting, fatigue, and aging on the biaxial flexural strength of yttria partially stabilized tetragonal zirconia ceramics were evaluated. Grinding lowers the mean strength and reliability under static and cyclic loading. In contrast, sandblasting provides a powerful tool for surface strengthening; it also hinders the propagation of the diffusion-controlled transformation during exposure to aqueous environments. By introducing moderate porosity, a reasonable compromise between the mechanical strength and the elastic modulus has been achieved. Such biscuit-sintered specimens also exhibited full hydrothermal stability. Novel experimental dental root posts were designed that exhibit certain advantages over the zirconia posts already in clinical use.