Development of Y-TZP Pre-Sintered Blocks for CAD-CAM Machining of Dental Prostheses

摘要

The aim of this work was to establish a route to produce pre-sintered blocks of Y-TZP (yttria stabilized tetragonal zirconia polycrystal) suitable to be machined in a commercial CAD-CAM system, used to manufacture crowns and bridge frameworks for dental applications. Two commercial Y-TZP powders were investigated. The powders were pressed with different compaction pressures (40 to 500 MPa) and pre-sintered at temperature ranging from 900 to 1100℃. Vickers hardness, biaxial flexural strength, and linear shrinkage could be correlated to the relative density of pre-sintered samples. Using an empirical equation, pre-sintered blocks with a pre-defined density could be prepared. The blocks withstood the machining in a CAD-CAM system, and the machined and sintered crowns presented good adaptation.