Process for the production of dental prostheses, dental prosthetic item which can be produced by the process and pre-sintered blank

摘要

Production of dental prosthesis involves (a) preparing a blank, (b) machining this by milling and (c) dense sintering at 1200-1650[deg]C, in which the blank is a pre-sintered material and has a green breaking strength of 31-50 MPa. Independent claims are also included for the following: (1) Dental prostheses made in this way; (2) Pre-sintered blanks of zirconium oxide ceramic, which consist of 91-98/45 wt.% zirconium (Zr) oxide, 0-3.5 wt.% hafnium (Hf) oxide, 1.5-6.0 wt.% yttrium (Y) oxide, 0.05-0.50 wt.% aluminum (Al), gallium (Ga), germanium (Ge) and/or indium (In) oxide(s) and 0-1.9 wt.% colorant (calculated as oxide) and have a green breaking strength of 31-50 MPa.