Friday, December 8, 2006

Kevlar-like Dental Composites

Filed under: Dentistry

Dr. Vistasp Karbhari, a professor of structural engineering at UC San Diego, has quadrupled the strength of dental composites, thanks to a material similar to kevlar:

Vistasp Karbhari, a professor of structural engineering at UC San Diego, has developed fiber-reinforced polymer composites as strong, lightweight materials for aerospace, automotive, civil and marine applications, so he thought, "If they work so well in highway bridges, why not dental bridges?"

In a paper scheduled for publication in 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, available at the Dental Materials website, shows that braided polyethylene fibers performed the best, boosting toughness by up to 433 percent compared to the composite alone...

The three products tested were a 3-millimeter-wide ribbon of unidirectional glass fibers, a 3-millimeter-wide ribbon of polyethylene fibers woven in a figure-8 stop-stitch leno-weave, and a 4-millimeter wide ribbon of polyethylene fibers woven in a biaxial braid. The resistance to breakage and various measures of toughness of the three preparations were compared to the dental composite alone.

Link...

                (2)