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Summary: Tantalum used for implants

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  • Summary: Tantalum used for implants

    Summary: Tantalum used for implants

    Thanks to all, how had send me some mails.
    This summary replaces completely me 1. resume, where several dates
    and references are missing. Excuse moi, nobody is perfect.

    First the references from the E-mails
    The follow references are from Scott Tashman, (tashman@bjc.hfh.edu)

    Alberius, P., Bone reactions to tantalum markers. A scanning electron
    microscopic study. Acta Anat (Basel) 115: 310-8, 1983.

    Ciccotti, M. G., Rothman, R. H., Hozack, W. J. and Moriarty, L.,
    Clinical and roentgenographic evaluation of hydroxyapatite-augmented
    and nonaugmented porous total hip arthroplasty.
    J Arthroplasty 9: 631-9,1994.

    Glantz, P. O., Bjorlin, G. and Sundstrom, B., Tissue reactions to
    some dental implant materials. An in vivo study in white rats.
    Odontol Revy 26: 231-8, 1975.

    Rune, B., Sarnas, K. V., Selvik, G. and Jacobsson, S., Movement of
    the cleft maxilla in infants relative to the frontal bone. A roentgen
    stereophotogrammetric study with the aid of metallic implants.
    Cleft Palate J 17: 155-74, 1980.

    Spolyar, J. L. and Canady, A., Component bone marker displacements
    revealed by image-corrected cephalometric analysis. A lateral
    cephalometric study of the cranium in normal and craniosynostosis--an
    implant study. Childs Nerv Syst 12: 640-53, 1996.

    Zitter, H. and Plenk, H., Jr., The electrochemical behavior of
    metallic implant materials as an indicator of their biocompatibility.
    J Biomed Mater Res 21: 881-96, 1987.

    Selvik, G., 1990, "Roentgen Stereophotogrammetric Analysis," Acta
    Radiologica, Vol. 31, pp. 113-126.

    Selvik, G., 1990, "Roentgen Stereophotogrammetry. A Method for the
    Study of the Kinematics of the Skeletal System,"
    Acta Orthop. Scand. Supp., Vol. 232, pp. 1-51.


    The follow references are from Fabio Baruffaldi, (baruffaldi@tecno.ior.it)

    H. Baldursson, L. Hansson, T.H. Olsson and G. Selvig, Migration of
    the acetabular socket after total hip replacement determined by
    roentgen stereophotogrammetry, Acta Orthop. Scand. 51 (1980) 535-540.

    A. Wykman, G. Selvig and I. Goldie, Subsidence of the femoral
    component in the noncemented total hip,
    Acta Orthop. Scand. 59 (1988) 635-637.

    B. Mjoberg, J. Brismar, L.I. Hansson, H. Petterson and G. Selvig,
    Definition of endoprosthetic loosening,
    Acta Orthop. Scand. 56 (1985)469-473.


    The follow reference is from Robert Poggie, (Bob.Poggie@Implex.com)

    "Biological Performance of Tantalum",
    Clinical Materials, 16 (1994), pp 167-173..


    The follow reference is from Niclas Borlin, (Niclas.Borlin@cs.umu.se)

    Kdrrholm: 'Roentgen Stereophotogrammetry, Review of orthopaedic
    applications', Acta Ortopaedica Scandinavica, 60 (4):491-503, 1989,


    I found some of the follow references

    Johansson CB , et al; Qualitative interfacial study between bone
    and tantalum, niobium or commercially pure titanium.
    (Biomaterials, 1990 May)

    Laass M , et al; [Investigations on secondary emission of metallic
    implant materials Ti and Ta following radiation]
    (Dtsch Stomatol,1991)

    Rabenseifner L , et al; [Is fracture healing in the presence of
    biocompatible implant materials tantalum and niobium different in
    comparison to steel implants?]
    (Z Orthop, 1984 May-Jun)

    Lopez GD, 1993
    Biodeterioration and corrosion of metallic implants and prostheses
    Medicina (B Aires) 53(3), 260-274 (1993)

    Aronson AS, 1985
    Tantalum markers in radiography. An assessment of tissue reactions.
    Skeletal Radiol 14(3), 207-211 (1985)

    Ungethum M, 1984
    Toxicology of metals and biocompatibility of metallic implant
    materials
    Z Orthop 122(1), 99-105 (1984)

    Pourbaix M, 1984
    Electrochemical corrosion of metallic biomaterials.
    Biomaterials 5(3), 122-134 (1984)

    Steinemann SG, 1996
    Metal implants and surface reactions.
    Injury 27, SC16-SC22 (1996)

    Cook SD, 1992
    Biocompatibility and biofunctionality of implanted materials.
    Alpha Omegan 85(4), 41-47 (1992)

    Peronneau P, 1981
    Biomaterials
    C R Seances Soc Biol Fil 175(5), 598-635 (1981)

    Rehberg HJ, 1973
    Metal implants and corrosion
    Dent Labor (Munch) 21(2), 123-125 (1973) (no abstract available)


    Some information about Tantalum

    General [http:// www.chronograph.com/tantalum.htm]
    Tantalum is a very heavy metal with a density more than twice that
    of steel. The physical properties of tantalum are similar to mild
    steel, except that tantalum has a (much) higher melting point (3000
    C). The tensile strength is about 345 MPa (50,000 psi), which can
    be approximately doubled by cold work. Tantalum is easy to
    fabricate. It is soft, ductile and malleable and can be worked into
    intricate forms. It can be welded by a number of techniques but
    requires completely inert conditions during welding. The metal is
    practically inert to many oxidizing and reducing acids, except
    fuming sulfuric. It is attacked by hot alkalis and hydrofluoric
    acid. However, it is very susceptible to hydrogen pickup and
    embrittlement. Its cost limits its use to thermocouple pockets,
    heating coils, bayonet heaters, coolers and condensers operating
    under severely corrosive conditions. Other applications include
    electrodes in thermionic valves, capacitors, surgical implants, and
    corrosion resistant linings in chemical industry.

    Advantages [http:// www. chronograph.com/tantalum.htm]
    Anodic film has better dielectric properties than Al; Very low
    ductile-brittle transition temperature; Very versatile aqueous
    corrosion resistance: inert to HCl, HNO3 , resistant to aqua regia,
    perchloric and chromic acids, oxides of nitrogen, chlorine and
    romine, organic acids, H2O2 and chlorides.

    Limitations [http:// www. chronograph.com/tantalum.htm]
    Combines with most gases above 500 C; Susceptible to hydrogen
    embrittlement; Attacked by nascent hydrogen and F2, HF, SO3 and
    alkalis above 5% concentration; 98% H2SO4 above 170 C; H3PO4 above
    190 C. Even so, attack is uniform (no pitting). In most
    environments, tantalum is comparable to glass in corrosion
    resistance, while it has physical and mechanical properties similar
    to mild steel. Tantalum resists most acids but is attacked by HF
    and by caustic. Unlike glass, however, it is also attacked by
    fuming sulfuric acid, sulfur dioxide, and chlorosulfonic acid. Due
    to its very high cost its use is limited to extremely severe
    corrosive conditions. For economy, tantalum is normally only used
    as lining or thin cladding (or as an electroplated coating on a
    copper or steel substrate). Most tantalum piping consists of
    thin-wall tubing inside of carbon steel pipe.(Pore free)
    tantalum-plated steel can be used in hot concentrated sulfuric acid
    and tantalum-plated copper can be immersed in nitric acid without
    attack of the substrate material.

    Industrial Application [http://www.chronograph.com/tantalum.htm]
    In the chemical process industries, tantalum is predominantly used
    in bayonet heaters, heat exchangers, orifice plates, valves, and
    tantalum-plated tubes. Tantalum patches are applied for the repair
    of holidays in glass-lined steel vessels. However, these must be
    electrically isolated from other metallic components in the vessel
    to avoid hydrogen embrittlement (cathode in galvanic couple).

    Checklist [http:// www. chronograph.com/tantalum.htm]
    * Potentially useful in :
    o hydrochloric acid (all concentrations; up to the boiling
    point)
    o nitric acid (all concentrations; up to the boiling point;
    except fuming !!)
    o sulfuric acid (all concentrations; up to the boiling point;
    except fuming !)

    * Corrosives to avoid :
    o alkalis (causing embrittlement)
    o hydrofluoric acid
    o red fuming nitric acid
    o fuming sulfuric acid

    Background information about Tantalum
    [WebElements 2.0: [University of Sheffield, England]
    http://www.shef.ac.uk/~chem/web-elements ]
    Tantalum is a grey, heavy, and very hard metal. When pure, it is
    ductile and can be drawn into fine wire, which is used as a filament
    for evaporating metals such as aluminium. Tantalum is almost
    completely immune to chemical attack at temperatures below 150 C, and
    is attacked only by hydrofluoric acid, acidic solutions containing
    the fluoride ion, and free sulphur trioxide. The element has a
    melting point exceeded only by tungsten and rhenium.
    * used to make alloys with desirable properties such as high melting
    point, high strength, good ductility
    * carbide graphite composite materials may be some of the hardest
    materials ever made
    * electrolytic capacitors
    * vacuum furnace parts
    * used to fabricate chemical process equipment, nuclear reactors,
    and aircraft and missile parts
    * immune to body liquids and nonirritating: therefore, widespread
    use for making surgical appliances
    * the oxide is used to make special glass with a high index of
    refraction for camera lenses
    * oxide is used to make special glass for camera lenses

    Biological information (abundances) [WebElements]
    Tantalum has no biological role.
    Levels in humans
    The following gives the abundances of the elements in humans.
    Blood: n.a.,but low mg*dm-3
    Bone: c. 0.03 ppm
    Liver: n.a. ppm
    Muscle n.a.,but low ppm
    Daily dietary intake: 0.001 mg
    Total mass of element in average (70 kg) person: c. 0.2 mg
    The following gives an indication as to toxicity.
    Toxic intake: moderately poisonous by ingestion
    Lethal intake: LD50 (chloride, oral, rat) = 1900 mg*kg-1

    Hazards and Risks [WebElements]
    Tantalum compounds are encountered rarely by most people. Tantalum
    metal does not normally cause problems but all tantalum compounds
    should be regarded as highly toxic. There are possibilities that
    tantalum compounds cause tumours.
    The metal dust presents a fire and explosion hazard.

    That's all folks for the moment.

    Beat Goepfert
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