Methods: Master dies made by cobalt-chrome alloy were fabricated to sumilate upper second premolar abutment tooth for porcelain fused to metal (PFM) crown. 5 Ce-TZP/Alumina nanocomposite crown frameworks (P-NanoZR, Panasonic healthcare, Japan) and 5 Y-TZP crown frameworks (cercon, DeguDent, Germany) were fabricated. The thickensses of the frameworks were 0.3mm like PFM crown frameworks. A load (1mm/min) was applied using a universal testing machine (AUTOGRAPH AGS-H, Shimadzu, Japan) on the center of the occlusal surface of the crown frameworks and measured the fracture strength. The t-test was used for the statistical analysis of fracture strength.
Results: The fracture loads of Ce-TZP/Alumina nanocomposite frameworks were 174.3±31.9N. Those of Y-TZP frameworks were 107.9±11.4N. The fracture strength of the Ce-TZP/Alumina nanocomposite framework was significantly higher than that of the Y-TZP framework (p<0.05).
Conclusion: The results suggested that we can reduce the amount of abutment tooth reduction using Ce-TZP/Alumina nanocomposite crown frameworks.