Mechanical properties of calcia stabilized zirconia following in vivo and in vitro aging

Abstract

Aging studies were done on calcia stabilized zirconia rods of 72% theoretical density to determine the effect of actual and simulated biological environments on their strength. They were aged without stress in vitro in Ringer's solution for 1, 2 and 4weeks or in vivo in rabbits for 12 weeks. Rods aged in vitro showed mean losses in bending strength of 16, 17 and 19% respectively after 1, 2 and 4 weeks of immersion, while those aged in vivo showed a mean loss of 25%. It was concluded that the material tested would be unsatisfactory as an orthopedic replacement because of the rapid decrease in strength which occurred when exposed to actual or simulated biological media.

Cluster-assembled cubic zirconia films with tunable and stable nanoscale morphology against thermal annealing

“…[11][12][13][14] The above mentioned properties are typical of the tetragonal and cubic high-temperature phases: 1,12 this has stimulated a considerable effort in the characterization of the conditions determining zirconia phase stability and transition. 12,[15][16][17] The high-temperature phases can be stabilized at room temperature by introducing oxygen deficiencies; this is usually obtained by doping zirconia with divalent (Mg 2þ , Ca 2þ ) and trivalent (Y 3þ , Sc 3þ ) cationic species. 9 The phase stability of zirconia polymorphs is substantially different when one considers nanoparticles: in pure ZrO 2 nanopowders and nanocrystalline zirconia, the tetragonal phase (t-ZrO 2 ) and the cubic phase (c-ZrO 2 ) are stable at room temperature.…”

Microstructure, bioactivity and osteoblast behavior of monoclinic zirconia coating with nanostructured surface

“…Tetragonal and cubic zirconia possess superior mechanical properties but undergo low temperature degradation (LTD) in water or water vapor [17,18]. LTD can reduce the mechanical strength and service life of the zirconia-based materials [19,20] and it is thought to be the main reason for the failure of zirconia artificial joint balls [21]. LTD, which depends on the microstructure and fabrication process, is accelerated by micro-cracks, high roughness and pores [17][18][19].…”