Drillings and fillings at the dentist's are always dreadful and make tooth decay treatment very unpleasant.

But British scientists have developed a new approach of fixing tooth decay, which could get rid of all the drillings, injections and fillings -- and unpleasantness, a press release by King's College London (KCL) said on Monday.

Dentists normally treat caries in a tooth by drilling to remove the decay and filling the tooth with a material such as amalgam or composite resin. But scientists at King's College London (KCL) took a different approach, one that re-builds the tooth and heals it without the need for drills, needles or amalgam.

By accelerating the natural process by which calcium and phosphate minerals re-enter the tooth to repair a defect, the device boosts the tooth's natural repair process.

The new method could be in use at the dentist's chair in the next 3 years, according to researchers.

The two-step method first prepares the damaged part of the enamel outer layer of the tooth, then uses a tiny electric current to 'push' minerals into the tooth to repair the damaged site. The defect is remineralised in a painless process that requires no drills, no injections and no filling materials.

Electric currents are already used by dentists to check the pulp or nerve of a tooth; the new device uses a far smaller current than that currently used on patients and which cannot be felt by the patient.

Professor Nigel Pitts from KCL said: "Not only is our device kinder to the patient and better for their teeth, but it's expected to be at least as cost-effective as current dental treatments. Along with fighting tooth decay, our device can also be used to whiten teeth."