ملخص البحث :

The preparation of zirconia waste powder by sieving the powder, milling and after that characterization of the zirconia recycled zirconia powder by the particle size analyses, XRD and SEM. Then preparation of the pre sintered Yttria-Tetragonal Polycrystall (3Y-TZP) blocks from the dental implant waste by different uniaxial pressures (75,100 and 145 MPa) and different presintering temperature (950, 1100°C). Then characterization of the Yttria-Tetragonal Polycrystall (3Y-TZP) blocks by XRD, SEM and EDS. The results showed (XRD) produce tetragonal phase with small amount of monoclinic phase of zirconia waste powder. While the results of the pre sintered Zirconia (3Y-TZP) showed disappeared the monoclinic phase and remained only the tetragonal phase and therefore it is possible to reuse the waste dental implant zirconia powder from used blocks and can be milling by the CAD/CAM and the suitable prefiltering temperature to reuse the powder only 950°C due to the similar properties to the commercial blocks.