Cobalt-chrome

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Cobalt-chrome disc with dental bridges and crowns manufactured using WorkNC Dental

Cobalt-chrome or cobalt-chromium (CoCr) is a metal alloy of cobalt and chromium. Cobalt-chrome has a very high specific strength and is commonly used in gas turbines, dental implants, and orthopedic implants.[1]

The alloy composition used in orthopedic implants is described in industry standard ASTM-F75: cobalt with 27 to 30% chromium, 5 to 7% molybdenum, and limits on other important elements such as manganese and silicon, less than 1%, iron, less than 0.75%, nickel, less than 0.5%, and carbon, nitrogen, tungsten, phosphorus, sulfur, boron etc.[1] Besides cobalt-chromium-molybdenum (CoCrMo), cobalt-nickel-chromium-molybdenum (CoNiCrMo) is also used for implants.[2] The possible toxicity of released Ni ions from CoNiCr alloys and also their limited frictional properties are a matter of concern in using these alloys as articulating components. Thus, CoCrMo is usually the dominant alloy for total joint arthroplasty.[2]

References[edit]

  1. ^ a b ARCAM ASTM F75 CoCr Alloy
  2. ^ a b Biomimetic Porous Titanium Scaffolds for Orthopedic and Dental Applications, Alireza Nouri, Peter D. Hodgson and Cui’e Wen (Institute for Technology Research and Innovation, Deakin University, Australia)