Replies to post #21988 on SiNtx Technologies Inc (SINT)

[boston745]

AMCs have serious phase instability issues.

The weak point of AMCs is their tetragonal crystalline phase that tends to transform into the monoclinic phase even under physiological conditions because of the presence of biological fluids and frictional heating.24 When evaluated in the laboratory under severe microseparation test mode, the monoclinic content of 36 mm diameter heads increased considerably from 15% to 30%.25 Monoclinic transformation is of concern, as it alters the phase integrity of the material and increases surface roughness, and potentially reduces sliding properties over time. Although AMCs are commonly used in THA, they have not yet firmly established a long-term track record in terms of wear and osteolysis, as compared with third-generation Al ceramics.

Why Zimmer would consider these is beyond me. As with ZTA, wear particles cause tissue inflammation and are potentially toxic at the nano level.