According to Vistasp Karbhari, a professor of structural engineering at UC San Diego, fiber-reinforced polymer composites, usually used for aerospace, automotive, civil and marine applications, may be used in dental bridges.
In a paper scheduled for publication in the journal Dental Materials, Karbhari and Howard Strassler, a professor and director of Operative Dentistry at the University of Maryland Dental School, report the results of detailed engineering tests on dental composites containing glass fibers as well as the type of polyethylene fibers used in bullet-proof vests.
Karbhari and Strassler found that the toughness of fiber-reinforced dental materials depends on the type and orientation of the fiber used. Their report shows that braided polyethylene fibers performed the best, boosting toughness by up to 433% compared to the composite alone.
Many of the strength and durability tests reported in the paper are not currently required by the US Food and Drug Administration, which regulates dental composites as class II prescription devices. The agency requires eight minimum tests plus biocompatibility tests to ensure that dental composites are safe and nontoxic.
“Fiber-reinforced composites are now widely used in the aerospace and automotive industries and the experience we have gained in these applications can be applied in a more rigorous way in dentistry and medicine to tailor performance to exacting requirements,” says Karbhari. “Our analyses show that we can optimize these materials to match and improve performance of teeth, for greater durability, toughness, and resistance to breakage.”
[EMax Health, December 7, 2006]