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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 dental implants and orthopedic implants.
Co-Cr alloys are most commonly used to make artificial joints including knee and hip joints due to high wear-resistance and biocompatibility. Co-Cr alloys tend to be corrosion resistant, which reduces complication with the surrounding tissues when implanted, and chemically inert that they minimize the possibility of irritation, allergic reaction, and immune response.