Commonly used zirconia ceramics in dentistry include: tetragonal zirconia ceramics, zirconia toughened ceramics, partially stabilized zirconia ceramics and nano-zirconia and alumina composite ceramics. All four zirconia ceramics contain stable tetragonal phases and are toughened by martensitic transformation, but have different microstructures, which also determine their different properties and suitable processing techniques. Specific differences include the use of different stabilizers to promote zirconia to form a stable tetragonal phase, and different strengthening mechanisms (nano-alumina toughened zirconia, tetragonal zirconia toughened alumina, tetragonal zirconia dispersed in cubic zirconia) , Different microstructures (crystal form, grain size).
Zirconia toughened ceramics have made great progress in the research of structural ceramics. There are also many types of toughened ceramics. Currently known additives that can stabilize zirconia are: magnesium oxide, calcium oxide, lanthanum oxide, yttrium oxide , cerium oxide and other single oxides or their composite oxides.
