The sound of the bristles scrubbing against the tooth enamel has an impact on how effectively people clean their teeth, a new study has found. (Photograph: Andrey Popov/Shutterstock)

Dec 29, 2015 | News Asia Pacific

CHōFU, Japan: In modulating the frequency and loudness of tooth brushing sounds, Japanese researchers have discovered that they were able to alter people’s perceptions of cleaning efficacy and overall satisfaction with their oral hygiene routine. In light of the findings, they have described details of a futuristic toothbrush that could change the way individuals perceive their daily brushing regimen.

In trials with volunteer teeth cleaners, Japanese researchers from the University of Electro-Communications in Chōfu investigated how modulating the brush sounds affects brushing efficacy and satisfaction. After recording the sound made in the mouth during brushing with a tiny microphone in a modified toothbrush, they fed that sound back to the volunteers via headphones in order to see what effect it would have. 

They found that in manipulating the pitch, frequency and loudness of the brushing sound, they were able to alter the volunteers' perceptions of comfort and accomplishment while brushing. Moreover, they reported that auditory stimulation not only made the task more comfortable for the users; they also felt like their teeth were cleaner at the end of the process.

According to the research team, one possible explanation for this might be that tooth brushing provides a 'negative reward' as one brushes the teeth to avoid developing caries. Subsequently, it was noted that users would not consider the impact of omitting the action until suffering from caries or other dental diseases. 

However, their results show that it is possible to motivate users by interactively manipulating the frequency of brushing sounds so that the task becomes more satisfying. While the prototype system in the study required the teeth cleaner to wear headphones—a method that is impractical to apply in real life—a bone conduction speaker system could be incorporated into future smart toothbrushes in order to create an amplified feedback loop in one's mouth.

In the next step of the research, the team will recruit volunteers to test the system in the comfort of their own bathrooms.

Details of the study were published in the International Journal of Arts and Technology, Vol. 8, No. 4, in the article “Modulating tooth brushing sounds to affect user impressions”.
From http://www.dental-tribune.com