Noise-cancelling device blocks out sound of dentist's drill

The sound of the dental drill is the prime cause of anxiety about dental treatment, with some patients avoiding trips to the dentist because of it. This new device could help address people’s fears and encourage them to seek the oral healthcare treatment they need.

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 plug the device into their MP3 player or mobile phone and then plug their 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.

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 ’adaptive filtering’ to cancel the sound from the drill even if the amplitude and frequency of the sound changes as the drill is being used.