BBC Teeth that can heal themselves Scientists hope there will be less need for fillings

American scientists claim to have found the answer to frequent fillings - a material that heals cavities.

They are working on a dental composite, which can actually encourage teeth to repair their own small holes.

The composite materials contain amorphous calcium phosphate (ACP), which can produce the natural mineral hydroxyapatite that is found in bones and teeth.

Dr Joe Antonucci, a polymer chemist with the National Institute of Standards and Technology in Gaithersburg and Dr Drago Skrtic, a physical chemist with the American Dental Association, presented their discoveries to the 222nd American Chemical Society.

Dr Antonucci said the polymer could have many dental uses.

And hopes are high that the material will be particularly useful in helping repair cavities in children with braces as they have problems in keeping their teeth clean of food and plaque.

"We are designing a specific material right now, which the American Dental Association believes can be used as an orthodontic adhesive.

"One of the problems with using orthodontics in children's mouths is that where they're attached to teeth by braces there tends to be demineralisation around that tooth.

"Using this kind of adhesive material that has the ability to remineralise the tooth, or at least to prevent demineralisation, we believe can be a distinct advantage."

Clinical trials

The scientists said the polymer could also be used in dental fillings to protect against secondary cavities and for root canal work.

Dr Antonucci said that although it is very useful in dealing with small cavities ACP will not work on larger holes.

"We don't think it's going to work with a large cavity because it only repairs small holes and is not as strong or hard as conventional filling materials, such as ceramic and glass.

"We don't envision it as a permanent filling. If we use it as a liner or base, then we would put a regular filling over it."

Dr Antonucci said it is also hoped that in the future ACP can be used for delicate bone repair such as in facial reconstruction and fractures.

ACP has already been used in toothpaste and chewing gum.

Clinical trials into its use as a temporary filling or dental adhesive are expected to start in a about a year.

A spokesman for the BDA welcomed the initial research and said they looked forward to the results of the clinical trials.

"The concept of teeth being able to remineralise, however, is not new. Indeed, this knowledge is one of the main reasons why the BDA encourages the use of fluoride toothpaste. In the early stages of decay, fluoride (in water or toothpaste) helps teeth remineralise, using the minerals in saliva."

-- Anonymous, August 26, 2001