Bioinertness and fracture toughness evaluation of the monoclinic zirconia surface film of Oxinium™ femoral head by Raman and cathodoluminescence spectroscopy

A comparative study of the mechanical behaviour of thermally oxidised commercially pure titanium and zirconium

“…2 shows the cross-sections of the thermally oxidised (TO) Ti and Zr specimens and Table 1 summarises the characteristics of the untreated and TO specimens. In consistency with the observations of other investigators (Aniolek et al, 2016;Leto et al, 2014), TO produced a dark oxide layer (OL) at the surface and an oxygen diffusion zone (ODZ) at the subsurface of both materials (Fig. 2).…”

“…Leto et al (2014) found that in the OL produced on Zr-2.5%Nb alloy by the commercial Oxinium TM process, there existed an interfacial region about 1 m thick between the OL and ODZ where a peculiar stoichiometric balance was achieved with a diffuse-type oxygen concentration. This would help to relieve the residual stresses arising from the thermal expansion mismatch between the surface ceramic OL and the metallic ODZ, and thus would contribute to enhanced integrity of the OL.…”

Ceramics and ceramic coatings in orthopaedics

“…There are no reported data for TiNbN, but its K IC range will likely be similar to TiN. An investigation of the fracture toughness of OxZr layers was performed by Leto et al using cathodoluminescence spectroscopy, resulting in K IC values of between 2.2 and 2.8 MPa m 1/2 [326]. Their results are similar to values observed for bulk monoclinic zirconia [327].…”

“…There are no reported hydrothermal stability studies for OxZr; but this layered ceramic is expected to be highly stable. As discussed previously, perhaps the only concerns for this coating are its thickness and hardness differential between the coating and the substrate, which could lead to delamination [326]. Finally, as presented in the prior section on corrosion, HAp coatings are designed to be hydrothermally active in order to facilitate osseointegration.…”

Bioceramics for Hip Joints: The Physical Chemistry Viewpoint

“…Such being the case, which testing protocols could prove the most appropriate? Our recent spectroscopic research suggests that the answer might lie in the physical chemistry of the biomaterial surfaces [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ], the issue of much contention in pre-clinical experimental testing of hip prostheses thus resulting shifted toward the possibility of specifying additional (and more effective) evaluation criteria and protocols. In the opinion of this author, new protocols should additionally rely on designing and monitoring the bearing surfaces at the molecular scale.…”