Gadget silences sound of dentist's drill

Nervous patients who cannot stand the sound of the dentist's drill could be offered relief by a new device.

Scientists at London universities have developed a gadget which cancels out the sound of the drill, leaving people free to enjoy their own music.

Patients simply unplug their headphones, plug the device into their MP3 player or mobile phone and then plug their headphones into the device.

Those using the device can still hear dentists and other staff speak to them about their treatment, since the tool only filters out the sounds of the high pitch of the drill.

The gadget contains a microphone and a chip which is able to analyse the incoming sound wave and then produces an inverted wave to cancel out the unwanted noise.

It also uses technology called adaptive filtering to "lock on" to sound waves and remove them, even if the amplitude and frequency change as the drill is being used.

Experts from King's College London, which is home to the UK's largest academic dental institute, Brunel University and London South Bank University are hoping to attract funding from an investor to develop the device further.

It was initially the brainchild of Prof Brian Millar at King's College London.

Prof Millar said: "Many people put off going to the dentist because of anxiety associated with the noise of the dentist's drill.

"But this device has the potential to make fear of the drill a thing of the past.

"The beauty of this gadget is that it would be fairly cost-effective for dentists to buy, and any patient with an MP3 player would be able to benefit from it, at no extra cost.

"What we need now is an investor to develop the product further, to enable us to bring this device to as many dental surgeries as possible, and help people whose fear of visiting the dentist stops them from seeking the oral healthcare they need."