Wear behavior of tetragonal zirconia polycrystal versus titanium and titanium alloy

Abstract

The aim of this study was to clarify the influence of tetragonal zirconia polycrystal (TZP) on the two-body wear behavior of titanium (Ti). Two-body wear tests were performed using TZP, two grades of cp-Ti or Ti alloy in distilled water, and the cross-sectional area of worn surfaces was measured to evaluate the wear behavior. In addition, the surface hardness and coefficient of friction were determined and an electron probe microanalysis performed to investigate the underlying mechanism of wear. The hardness of TZP was much greater than that of Ti. The coefficient of friction between Ti and Ti showed a higher value than the Ti/TZP combination. Ti was more susceptible to wear by both TZP and Ti than TZP, indicating that the mechanism of wear between TZP and Ti was abrasive wear, whereas that between Ti and Ti was adhesive wear. No remarkable difference in the amount of wear in Ti was observed between TZP and Ti as the opposite material, despite the hardness value of Ti being much smaller than that of TZP.

Fatigue induced changes in conical implant–abutment connections

“…NA implants are made of cold worked cp-titanium resulting in an enhanced Vickers hardness (unpublished data). Increasing the hardness of a metal is usually accompanied with an increased yield strength and therefore the material exhibits a higher threshold for the occurrence of plastic deformation [40,42]. All implants show chipping and plastic deformation, suggesting forces exceeding the elastic properties of the material [40].…”

Influence of the difference between implant body and screw materials on abutment screw loosening

“…The results of the t-test showed a significant difference before and after tests in the groups fastened with grade 4 pure titanium screws, with ZrB-Ti4S showing the highest loosening torque ratio. In terms of the Vickers hardness of the materials used in this study, it is reportedly 177 Hv for grade 4 pure titanium, 256 Hv for Ti-6Al-4V, and 1356 Hv for Y-TZP 5) , and these were the combinations used in the study that showed the greatest difference in hardness between materials. Therefore, cyclic loading tests were also performed at the centric point.…”

“…When a screw is tightened, a frictional force occurs at the contact surface of the screw, and shear stress due to the torsional torque and axial stress caused by the axial force are applied to the screw 29) . Kanbara et al 5) reported that in wear tests on pure titanium and Ti-6Al-4V, abrasive wear was caused by Y-TZP. Therefore, abutment screws for zirconia implants should be fabricated out of zirconia.…”

“…Avivi-Arber and Zarb reported that abutment screw loosening is the most frequent mechanical complication 2) . It reportedly causes component failure, peri-implantitis, and other issues that in some cases lead to serious complications [3][4][5] . On the incidence of abutment screw loosening, Jemt et al 6,7) reported that of single-tooth restoration cases, 55.7% experience abutment screw loosening within 1 year after the superstructure has been set 6) , with 24.2% after 2 weeks and 5.7% after 4 weeks 7) .…”

Metal stain on monolithic zirconia restoration: A case report

“…However, an in vitro study on wear between titanium alloy and zirconia20 has reported that the amount of wear of titanium alloy opposing zirconia was 20 times higher than that of the zirconia, and pointed out that this is due to the hardness of zirconia. In addition, a previous study20 has also described that, while adhesive wear occurred between metal and metal, abrasive wear occurred between zirconia and metal. In the present case, a secondary electron image revealed the presence of Ni-Cr alloy as a foreign body on the zirconia surface (Fig.…”