The purpose of this in vitro study was to investigate the fracture strength and phase structure of different high-translucency zirconia ceramics depending on the changes in sintering duration and thermocycling.


 Thermocycling was applied to half the specimens.  For nonthermocycled specimens, the fracture strength of NEX was significantly higher than that of KAT (P<.001).  Thermocycling had a significant effect on fracture strength depending on sintering duration and zirconia ceramic interaction (P=.046).


 Thermocycling decreased the fracture strength of both zirconias, except when the sintering duration was 2 hours for NEX. 
THERM