A new tooth decay detector may help dentists detect tooth decay early.
The device, called CarieScan PRO, clips onto the mouth and through the tooth passes a small electrical current.
Traffic light colours indicate the level of decay, which give health experts a correct status of the problem, reports Sky News.
Wembley-based dentist Dr Martin Delahaye said: "What I've been able to do is diagnose decay early and make sure it's treated with fluoride varnish rather than putting in a filling."
Scientists in Scotland developed the CarieScan PRO.
The British Dental Association's scientific advisor Professor Damien Walmsley said: "The CarieScan PRO is an interesting innovation, and it's great too, that the concept and design comes from a UK company.
"We look forward to seeing the results of future clinical trials to establish its benefits."