Bioactive glass

Bioactive glass

Bioactive glasses are a group of surface reactive glass-ceramics and include the original bioactive glass, Bioglass. The biocompatibility of these glasses has led them to be investigated extensively for use as implant materials in the human body to repair and replace diseased or damaged bone.

History

Larry Hench and colleagues at the University of Florida first developed these materials in the late 1960s and have been further developed by his research team at the Imperial College London and other researchers worldwide.

Compositions

There have been many variations on the original composition which was Food and Drug Administration (FDA) approved and termed bioglass. This composition is known as 45S5. Other compositions are in the list below.
*45S5: 46.1 mol% SiO2, 26.9 mol% CaO, 24.4 mol% Na2O and 2.5 mol% P2O5. Bioglass
*58S: 60 mol% SiO2, 36 mol% CaO and 4 mol% P2O5.
*S70C30: 70 mol% SiO2, 30 mol% CaO.

Structure

Solid state NMR spectroscopy has been very useful in elucidating the structure of amorphous solids. Bioactive glasses have been studied by 29Si and 31P solid state MAS NMR spectroscopy. The chemical shift from MAS NMR is indicative of the type of chemical species present in the glass. The 29Si MAS NMR spectrscopy showed that Bioglass 45S5 was a Q2 type-structure with a small amount of Q3; i.e., silicate chains with a few crosslinks. The 31P MAS NMR indicated a Q0 species; i.e., PO44- with predominately sodium cations. (Lockyer et al. 1995)

Medical Applications

Bioactive glasses have many applications but these are primarily in the areas of bone repair and bone regeneration via tissue engineering.
*Synthetic bone graft materials for general orthopaedic, craniofacial (bones of the skull and face), maxillofacial and periodontal (the bone structure that supports teeth) repair. These are available to surgeons in a particulate form.
*Cochlear implants.
*Bone tissue engineering scaffolds. These are being investigated in many forms, in particular as porous (contains pores into which cells can grow and fluids can travel) 3-dimensional scaffolds.
*Treating Dentine hypersensitivity and promoting enamel remineralization in the form of NovaMin.ReferencesLockyer, M. W. G., Holland, D. & Dupree, R., NMR investigation of the structureof some bioactive and related glasses. J. Non-Crys. Sol., 1995, 188, 207-219.

External links

NovaBone Products in Alachua, FL manufactures and markets bioactive glass. The Musculoskeletal Transplant Foundation distributes NovaBone internationally. Visit: www.novabone.com and www.mtf.org
Vivoxid Ltd in Finland manufactures, markets and sells bioactive glass.Visit: www.vivoxid.com


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Glass — This article is about the material. For other uses, see Glass (disambiguation). Moldavite, a natural glass formed by meteorite impact, from Besednice, Bohemia …   Wikipedia

  • Glass electrode — A glass electrode is a type of ion selective electrode made of a doped glass membrane that is sensitive to a specific ion. It is an important part of the instrumentation for chemical analysis and physico chemical studies. In modern practice,… …   Wikipedia

  • Glass transition — The liquid glass transition (or glass transition for short) is the reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle state into a molten or rubber like state …   Wikipedia

  • Glass microsphere — For microspheres made of other materials, see Microsphere. SEM micrograph of a glass microsphere in concrete Glass microspheres are microscopic spheres of glass manufactured for a wide variety of uses in research, medicine, consumer goods and… …   Wikipedia

  • Lead glass — Swarovski flacon. Lead glass is a variety of glass in which lead replaces the calcium content of a typical potash glass.[1] Lead glass contains typically 18–40 weight% lead(II) oxide (PbO), while modern lead …   Wikipedia

  • Cranberry glass — Vintage cranberry glass bowl Cranberry glass (or Gold Ruby glass as it is known in Europe, or Rubino Oro as it is known by glass workers) is a red glass made by adding gold(III) chloride to molten glass. Tin, in the form of stannous chloride, is… …   Wikipedia

  • Milk glass — Decorative pedestal milk glass bowl Milk glass is an opaque or translucent,[citation needed] milky white or colored glass, blown or pressed into a wide variety of shapes. First made in Venice in the 16th century, colors include blue, pin …   Wikipedia

  • Chemically strengthened glass — is a type of glass that has increased strength as a result of a post production chemical process. When broken, it still shatters in long pointed splinters similar to float glass. For this reason, it is not considered a safety glass and must be… …   Wikipedia

  • Chalcogenide glass — A chalcogenide glass (hard ch as in chemistry ) is a glass containing one or more chalcogenide elements. These are Group 16 in the periodic table e.g. sulfur, selenium or tellurium. Such glasses are covalently bonded materials and may be… …   Wikipedia

  • Cobalt glass — for decoration Cobalt glass is a deep blue colored glass prepared by adding cobalt compounds to the molten glass. It is appreciated for its attractive color. It is also used as an optical filter in flame tests to filter out the yellow flame… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”