June
11, 2003
(National Institute of Standards and
Technology) -- Dentists beware: Teeth soon may be smart
enough to fix themselves.
"Smart materials" invented at the
National Institute of Standards and Technology (NIST)
soon may be available that stimulate repair of defective
teeth. Laboratory studies show that these composites,
made of amorphous (loosely structured) calcium phosphate
embedded in polymers, can promote re-growth of natural
tooth structures efficiently. In the presence of
saliva-like solutions, the material releases calcium and
phosphate ions, forming a crystalline calcium phosphate
similar to the mineral found naturally in teeth and
bone. Developed through a long-standing partnership
between NIST and the American Dental Association (ADA),
these bioactive, biocompatible materials are described
in a forthcoming paper in the NIST Journal of Research.
Plans are being made for clinical
trials, and several companies have expressed interest in
licensing the patented material once a production-ready
form is available. Initial applications include adhesive
cements that minimize the decay that often occurs under
orthodontic braces. The material also can be used as an
anti-cavity liner underneath conventional fillings and
possibly in root canal therapy.
NIST and ADA scientists continue to
enhance the material's physicochemical and mechanical
properties and remineralizing behavior, thereby
extending its dental and even orthopedic applications.
For example, the researchers found that adding silica
and zirconia to the material during processing
stabilizes the amorphous calcium phosphate against
premature internal formation of crystals, thereby
achieving sustained release of calcium and phosphate
over a longer period of time.
