Names: Zirconia, zirconium oxide, zirconium dioxide (ZrO2), yttria-stabilized zirconia (YSZ) Terms: Phase Transformation Toughening: The naturally occurring process by which cubic grains within stabilized zirconia constrain tetragonal precipitates, effectively closing advancing cracks and resulting in a sort of self-healing of the material. Fracture Toughness: A property that describes the ability of a material with inherent microstructural flaws to resist fracture via crack growth and propagation. Plasticity: The deformation of a material undergoing non-reversible changes of shape in response to applied forces. Brittle Fracture: No apparent plastic deformation takes place before fracture. Ductile Fracture: Extensive plastic deformation takes place, characterized by slow propagation and absorption of large amounts of energy, before fracture.
Zirconia is one of the most studied ceramic materials in the world for uses ranging from telecommunications to the new energy of the future to environmentally-friendly products. In clinical dentistry, it is widely used for the fabrication of crown copings, bridge frameworks and custom implant abutments. Its durability, biocompatibility, natural esthetics and low cost when compared to alternative restorative materials make it the ideal solution for a variety of clinical applications. More recently, dental use is trending toward full-contour (monolithic) zirconia — that is, solid zirconia restorations with no porcelain overlay. Ongoing material advancements have produced the strongest and most reliable all-ceramic restoration to date, making zirconia an ideal alternative solution wherever traditional metal or PFM restorations might be prescribed.