Basic information on material and use in medicine

Used in medicine for already 30 years

The zirconia oxide or more precisely Y - TZP (Yttrium stabilized tetragonal zirconia polycrystals) stabilized by yttrium oxide has been successfully used in orthopedics since 1969 for the production of coxa artificial heads. There have been documented more than 400 000 uses worldwide. Due to great number of wear tests and mechanical load tests it can be determined that mechanical properties of Y - TZP show satisfactory strength when used in orthopedics or dental implants even after 50 years of physiological use. Y - TZP has proved in various in vivo and in vitro tests neither mutagenic (chromosome aberrations test) nor carcinogenic (Ames test) effects. There has been made an agreement proving that at contact of zircone - oxide ceramics with a bone or soft tissues there are not expected any local toxic reactions.

The zircone oxide is used in dentistry in the form of stock root posts, jaw-orthopedic briquettes or as implant attachment. The processing of zirconia oxide was carried out only in heavily cemented condition and it is connected with extreme tool wearing and substantial time demand.

CERON system offers, with respect to the material processing in pre-cemented condition, a new economic fabrication technique for crowns and bridges from zirconia oxide.

Significant strength enhancement
The static fracture strength of cutter-processed 3 - segment bridges in the lateral part from zirconia oxide is in comparison with 3 - segment bridge from the pressed ceramics (EMPRESS II) or infiltration ceramics (InCeram Alumina) higher by the factor 2 - 3. The permanent strength of Y - TZP exceeds the strength of InCeram Alumina 3 times. When comparing fracture strength of all-ceramic crowns in the lateral part, the zirconia oxide restorations fabricated by means of Cercon system show significantly higher values than other all-ceramic systems commonly presented on the market (InCeram Zirconia, Procera, Empress II). In vitro experiments for fracture strength with crowns in the frontal part have proved the values for Cercon restorations comparable with values for metal-ceramic crowns on noble metal alloys basis.