Alloys for Surgical Implants

In some cases, 200- to 300-fold concentrations of maximum normal values could be demonstrated in body fluids and in implants surrounding tissue (Hildebrand et al. 1988, 1996b Laffargue et al. 1998). 

Cobalt seems to produce similar effects to those of Ni and Cr. Most authors agree that secondary harmful reactions are not directly generated by the presence of ions, but by their still scarcely known metabolites. The degree of oxidation and the formation of metallo-organic complexes may play an essential role, in particular for Cr, the primary ionic form of which after liberation is the trivalent ion. Its active toxic, allergenic and carcinogenic form, however, is the hex-avalent ion (Bartolozzi and Black 1985). 

The alloy composition has less importance than the physico-chemical structure and characteristics the amount of ions released from Co-Cr alloys is similar to that liberated from stainless steel (Pazaglia etal. 1987). 

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ASTM-F562 (2000), Standard Specification for Wrought Cobalt-35 Nickel-20 Chromium-lO Molybdenum Alloy for Surgical Implant Applications, American Society f[Pg.357]

Fraker, A.C., Ruff, A.W., Sung, P. von Orden, A.C. and Speck, K.M. (1983) Surface Preparation and Corrosion Behaviour of Titanium Alloys for Surgical Implants, in Titanium Alloys in Surgical Implants, (eds H.A. Cuckey and F. Kubli), ASTM STP 796, pp. 206-219. 

Semlitsch, M., Staub, F. and Weber, H. (1985) Development of a Vital, High-Strength Titanium Aluminium-Niobium Alloy for Surgical Implants Proc. 5th European Conf. on Biomaterials, Paris, Sept. 4-6, 1985. 

Steinemann, S.G., Mausli, P.-A., Szmukler-Moncler, S., Semlitsch, M., Pohler, O., Hintermann, H.-E. and Perren, S.M. (1993) Beta-Titanium Alloy for Surgical Implants, Proc. of the 7th World Conf. on Titanium, pp. 2689-2696. 

Steineman, S.G. (1985) Corrosion of Titanium and Titanium Alloys For Surgical Implant, in Lutergering, G., Swicker, U., Bunk, W. (eds). Titanium, Science, and Technology, Volume 2, DG fiir Metal. e.V. Oberuresel, Berlin, 1373-1379. 

F 1295, Specification for Wrought Titanium-6 Aluminum-7 Niobium Alloy for Surgical Implant Applications (UNS R56700)... 

Potentiostatic measurements were made in Hanks solution. The solution was in a closed vessel and was not aerated or deaerated. Source A.C. Fraker etal.. Surface Preparation and Corrosion of Titanium Alloys for Surgical Implants... 

ASTM F1295 6A1-4V niobium alloy for surgical implant appbcations... 

ASTM F136 6A1-4V ELI alloy for surgical implant applications... 

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