H. Tomas et al., EFFECTS OF CO-CR CORROSION PRODUCTS AND CORRESPONDING SEPARATE METAL-IONS ON HUMAN OSTEOBLAST-LIKE CELL-CULTURES, Journal of materials science. Materials in medicine, 7(5), 1996, pp. 291-296
The cytocompatibility of the degradation products of a Co-Cr orthopaed
ic alloy was investigated with particular focus on the dose-effect of
an electrochemically dissolved alloy extract and of the corresponding
separate metal ions on human osteogenic bone marrow derived cells. The
extract solution contained 15 ppm of Co and 8 ppm of Cr as analysed b
y atomic absorption spectroscopy. Stock salt solutions of CoCl2 . 6H(2
)O, CrCl3 . 6H(2)O and Na2CrO4 at corresponding concentrations were al
so prepared. Several dilutions of the above metallic solutions were te
sted for a period of 21 days on cells (third subculture) cultured in a
lpha-minimal essential medium containing foetal bovine serum and suppl
emented with antibiotics, dexamethasone ascorbic acid and beta-glycero
phosphate. The osteoblast response to the presence of metal ions was e
valuated by several biochemical parameters: cell viability (MTT reduct
ion by intracellular enzymes), alkaline phosphatase activity (an osteo
blast marker) and protein production (both intracellular and extracell
ular). Co-Cr corrosion products showed opposite effects to their respe
ctive metal salts only on day 1. With time the different metal solutio
ns presented a similar pattern of inhibition. These results suggest th
at impaired bone formation in vitro can occur in the presence of Co-Cr
corrosion products.