Metal biomaterial

Pourbaix, M., Electrochemical Corrosion of Metallic Biomaterials , Biomaterials, 5, 122-134 (1984)... 

Metallic biomaterials (metals such as Ti or its alloys and others) are used for the manufacture of orthopaedic implants due to their excellent biocompatibility with respect to electrical and thermal conductivity and their mechanical properties, e.g., for hard tissue replacement such as total hip and knee joints, for fracture healing aids such as bone plates and screws or dental implants. For example, Co-Cr-Mo alloys are employed for metal-on-metal hip bearings in total joint replacements. Problems with implants occur because of ion release in patients with metal implants. To control this ion release, the ultratrace determination of Co, Cr and Mo in the blood (or serum) and urine of patients with Co-Cr-Mo alloy hip implants is carried out routinely in the author s laboratory. The trace metal determination of Co, Cr and Mo in complex matrices such as urine and blood by ICP-MS is not trivial due to the low concentrations expected in the sub-ngmF1 range, the possible danger of contamination during sample collection, sample preparation and the... 

Garvey, B. T., and Bizios, R., A transmission electron microscopy examination of the interface between osteoblasts and metal biomaterials. J. Biomed. Mat. Res. 29 (8), 987-992 (1995). 

Most metallic biomaterials fall into one of four categories stainless steels, titanium and titanium-based alloys, cobalt-chromium alloys, and amalgams. Additionally, research is under way on a number of... 

Next-generation metallic biomaterials include porous titanium alloys and porous CoCrMo with elastic moduli that more closely mimic that of human bone nickel-titanium alloys with shape-memory properties for dental braces and medical staples rare earth magnets such as the NdFeB family for dental fixatives and titanium alloys or stainless steel coated with hydroxyapatite for improved bioactivity for bone replacement. The corrosion resistance, biocompatibility, and mechanical properties of many of these materials still must be optimized for example, the toxicity and carcinogenic nature of nickel released from NiTi alloys is a concern. ... 

JL Gilbert, SM Smith, EP Lautenschlager. Scanning electrochemical microscopy of metallic biomaterials—reaction-rate and ion release imaging modes. J Biomed Mater Res 27 1357-1366, 1993. 

This relationship between allergy and metallic biomaterials has also been confirmed for alloys used in dentistry Ni, Cr and Co in non-precious alloys (Hildebrand et al. 1989a, 1989b), and Hg and Ag in dental amalgams (Veronetal. 1986 Horsted-Bind-slev et al. 1997 Sandborgh-Englund et al. 

Particular attention must be given to any metallic biomaterial or medical device, and both known and new devices should be submitted to continuous medical survey in order to avoid as early as possible any potentially unfavorable tissue reactions. 

Conducting polymers are an exciting alternative to conventional metal biomaterials for use in a range of implant applications with a requirement for electroactivity. The development... 

Non-Metallic Biomaterials for Tooth Repair and Replacement (ISBN 978-0-85709-244-1)... 

Schwach, G., Coudane, J., Engel, R. and Vert, M. (2(X)2) Influence of polymerization conditions on the hydrolytic degradation of poly(DL-lactide) polymerized in the presence of stannous octoate or zinc-metal. Biomaterials, 23, 993—1002. 

Biomaterials in general are based on the materials groups metals, polymers and ceramics [3]. Typical metallic biomaterials are based on stainless steel, cobolt based alloys and titanium or titanium alloys and amalgam alloys. Polymeric biomaterial composites from monomers are based on amides, ethylene, propylene, styrene, methacrylates, and/or methyl methacrylates. Biomaterials based on ceramics are found within aU the classical ceramic families traditional ceramics, special ceramics, glasses, glass-ceramics, coatings and chemically bonded ceramics (CBC). 

Although a variety of metallic biomaterials have been employed in joint arthroplasty, alloys of cobalt, 28% chromium, and 6% molybdenum (CoCr) are viewed as the gold standard for use in MOM bearings. CoCr alloy is also considered the gold standard as a femoral head material for articulations against conventional as well as highly crosslinked UHMWPE (Muratoglu and Kurtz 2002, Sauer and Anthony 1998). CoCr alloys (e.g., Vitallium ) have been used for hip replacements since 1938, when the biomaterial was employed in the Smith-Petersen mold arthroplasty (Smith-Petersen 1948). 

Park J.B. 1995. Metallic biomaterials. In The biomedical engineering handbook. ].D. Bronzino, Ed. Boca Raton, EL CRC Press. 

A further direction of advancement was originated by the progress being made in research and surgery and by the demand for materials with special properties for special applications. For these cases the materials, which are often composite materials, had to be tailored to the intended application. One example is the development of the alloy TiTa30 which in its thermal expansion coefficient is very similar to alumina and can therefore be crackfree bonded with the ceramic. This material is used as a dental implant. The metallic biomaterial which can resist bending stresses is inserted into the jaw. The upper part of the implant consisting of alumina, which shows a smaller deposition of plaque than the metallic materials. 

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