Washington: With an invention of "smart materials" that stimulate repair of defective teeth, dentists could soon be out of business.

Invented at the National Institute of Standards and Technology (NIST), the 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 issue of the NIST 'Journal of Research'.

Initial applications include adhesive cements that minimise 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.

The scientists continue to enhance the material's physicochemical and mechanical properties and remineralising behaviour, thereby extending its dental and even orthopaedic applications.

For example, the researchers found that adding silica and zirconia to the material during processing stabilises the amorphous calcium phosphate against premature internal formation of crystals, thereby achieving sustained release of calcium and phosphate over a longer period of time.

ANI