Influence of heat treatment on the microstructure and the physical and mechanical properties of dental highly translucent zirconia
Konstantinos Dimitriadis, Athanasios K. Sfikas, Spyros Kamnis, Pepie Tsolka, Simeon Agathopoulos
Abstract
PURPOSE: study. MATERIALS AND METHODS: values smaller than 5% were considered statistically significant. RESULTS: A homogenous microstructure, with no residual porosity and grains sized between 500 and 450 nm for group A and B, respectively, was observed. Crystalline yttria-stabilized tetragonal zirconia was exclusively registered in the X-ray diffractograms. The mechanical properties decreased after the heat treatment procedure, but the differences were not statistically significant. CONCLUSION: The produced zirconia ceramic materials can be safely (i.e., according to the ISO 6872) used in extensive fixed prosthetic restorations, such as substructure ceramics for three-unit prostheses involving the molar restoration and substructure ceramics for prostheses involving four or more units. Consequently, milling technology is an effective manufacturing technology for producing zirconia substructures for dental fixed all-ceramic prosthetic restorations.