Preparation and properties of dental zirconia ceramics

Y2O3-stabilized tetragonal zirconia polycrystalline (Y-TZP) ceramics with high-performance were prepared for dental application by use of the micro-emulsion and two-step sintering method. The crystal phase, morphology, and microstructure of the reaction products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). XRD results show that the ceramics mainly consist of tetragonal zirconia. Physical and mechanical properties test results show that the bending strength, fracture toughness, and the density of full sintered Y-TZP ceramics are 1150 MPa, 5.53 MPa.m(1/2), and 6.08 g/cm(3), respectively, which suggest that the material is relatively suitable for dental restoration. The dental base crown machined with this material by CAD/CAM system exhibits a verisimilitude configuration and the material's expansion coefficient well matches that of the glaze. These results further indicate that the product can be used as a promising new ceramic material to fabricate dental base crowns and bridges. (C) 2008 University of Science and Technology Beijing. All rights reserved.