Dr. Christian Rüssel and his colleagues of the Otto-Schott-Institute for Glass Chemistry succeeded in producing a new kind of glass ceramic with a nanocrystalline structure. Ceramic materials used so far are not very suitable for bridges, as their strengths are mostly not high enough. After all, these are worn as much as healthy teeth. “What the natural tooth enamel has to endure also goes for dentures, inlays, or bridges,” says glass chemist Dr. Rüssel, a professor at the Friedrich Schiller University Jena in Germany.
Glass-ceramics on the basis of magnesium-, aluminum-, and silicon oxide are distinguished by their enormous strength. “We achieve a strength 5 times higher than with comparable denture ceramics available today,” Dr. Rüssel explains. He and his researchers have been working for a while on high density ceramics, but so far only for use in other fields (ie, as the basis of new efficient computer hard drives). To achieve the characteristics for dentures, the glass ceramics are produced according to an exactly specified temperature scheme. “This procedure determines the crystallisation crucial for the strength of the product,” Dr. Rüssel explains. The secret of the Jena glass ceramic lies in its consistence of nanocrystals. The size of these is at most 100 nm in general. “They are too small to strongly disperse light and therefore the ceramic looks translucent, like a natural tooth,” he says.
A lot of developing work is necessary until the materials from the Jena Otto-Schott-Institute will be able to be used as dentures, but the groundwork is done. The research results are published in the online edition of the Journal of Biomedical Materials Research.
(Source: ScienceDaily, January 5, 2012)
