OBJECTIVETo evaluate the influence of mechanical property of tooth-like yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) by adding rare earth oxide as colorants.

METHODSSix kinds of tooth-like Y-TZP were made by introducing internal coloration technology. The colorants included rare earth oxide (Pr6O11, CeO2, Er2O3) and transition element oxide (MnO2). Mechanical properties (flexural strength, vickers hardness and fracture toughness) were tested. Microstructure was examined by scanning electron microscope(SEM), and the fracture model was analyzed.

RESULTSThe range of flexural strength of the six kinds of tooth-like Y-TZP were (792 +/- 20)-(960 +/- 17) MPa, the fracture toughness were (4.72 +/- 0.31)-(5.64 +/- 0.38) MPam(1/2), and the vickers hardness were (1332 +/- 19)-(1380 +/- 17) MPa. SEM observation on the cross section of the six kinds of sintered composites showed a relatively dense polycrystal structure, and the fracture models was mixed type.

CONCLUSIONTooth-like Y-TZP is acquired with better mechanical properties (fracture toughness and vickers hardness) by adding rare earth oxide as colorants. It is available for clinical application.