A new idea to encourage teeth to repair themselves may see the end of the fear-inducing sound of the dentist's drill, researchers say.

Researchers at King's College London believe electricity can be used to strengthen a tooth by forcing minerals into the layer of enamel.

They hope it will get rid of the need for drills, injections and fillings.

A company has been set up to bring the technique to the dentist's chair in the next three years.

Minerals such as calcium and phosphate naturally flow in and out of the tooth. Acid produced by bacteria munching on food in the mouth help leach minerals out.

The group at King's apply a mineral cocktail and then use a small electric current to drive the minerals deep into the tooth.

This is the launch of a company - Reminova - which will be based in Perth, Scotland.

Prof Nigel Pitts, one of the inventors and an investor in the new company, told the BBC: "This is early stage - you don't start with the finished product - but we're excited because we think it is groundbreaking.

He said the technology had the potential to replace the need for many existing fillings, but could not tackle large "end-stage" cavities.

"What it won’t do is physically re-grow a tooth," he added.