| By helping to invent and improve materials,
tools and methods, NIST has been advancing the practice of dentistry for nearly 80 years. |
The practice of dentistry and
the National Institute of Standards and Technology
(NIST) go back a long way--back to 1919 in fact, when the U.S. Army asked NIST, then the
National Bureau of Standards, to look into the physical factors behind good and bad
metal-based amalgams for filling teeth. Ten years later, NIST's laboratory predecessor
began what continues to be a collaboration with the American Dental Association whose goal
has been the development, refinement and general improvement of medical practice through
the invention of new dental materials, tools and methods. In
addition to the introduction of new polymeric and mineral-based materials for aesthetic
tooth restoration and the development of metallic alloys for amalgams, other results from
the collaborative research between NIST and the ADA include the panoramic X-ray and the
water-driven precursor of today's air-driven handpiece with which dentists wield drills,
cleaning heads and other tools. Besides increasing the quality of patient care, both of
these instruments have saved the nation several billion dollars by reducing the time
required by dentists to treat patients and by increasing the comfort and effectiveness of
dental treatment. It was estimated in 1987 that the increased durability of composite
restorations, and thereby the reduction of replacement costs of previously used materials,
saved Americans more than the combined appropriated budgets of NIST, the ADA and the
National Institute of Dental Research.
There are many ongoing recent research projects at NIST
that aim to improve dentistry. One project seeks better understanding of the mechanism by
which dental biomaterials adhere to tissues. Biodegradable materials are being developed
for hard tissue repair and are being evaluated clinically. Improved resins that have
higher resistance to degradation by oral fluids and that reduce polymerization shrinkage
are being developed. An in-mouth radiation shield to protect cancer patients from
secondary radiation emitted from metallic restorations during radiation therapy is in
clinical trials with industrial sponsorship. The interfaces between fillers and resins of
resin-based composite restoratives are being investigated with the goal of improving
interfacial strength and durability of composite restorations. Work is in progress with
the NIST Metallurgy Division
to develop a metallic, mercury-free restorative that can be used like dental amalgam. |
