ScienceDaily

An innovative device which cancels out the noise of the dental drill could spell the end of people's anxiety about trips to the dentist, according to experts at King's College London, Brunel University and London South Bank University, who pioneered the invention.

The prototype device works in a similar way to noise-cancelling headphones but is designed to deal with the very high pitch of the dental drill. Patients would simply unplug their headphones, plug the device into their MP3 player or mobile phone, and then plug the headphones into the device, allowing them to listen to their own music while completely blocking out the unpleasant sound of the drill and suction equipment. The patient can still hear the dentist and other members of the dental team speaking to them but other unwanted sounds are filtered out by the device.

Containing a microphone and a chip that analyses the incoming sound wave, the device produces an inverted wave to cancel out unwanted noise. It also uses technology called 'adaptive filtering' where electronic filters lock onto sound waves and removes them, even if the amplitude and frequency change as the drill is being used.

The device was initially the brainchild of Professor Brian Millar at King's College London's Dental Institute who was inspired initially by carmaker Lotus' efforts to develop a system that removed unpleasant road noise, while still allowing drivers to hear emergency sirens. Then with over a decade of collaboration with engineering researchers at Brunel University and London South Bank University, a prototype has been designed, built and successfully evaluated.

The product is not yet available to dental practitioners.