  Early detection of dental disease is crucial to prevent adverse outcomes.
Today, dental X-rays are currently the most accurate gold standard for dental
disease detection. Unfortunately, regular X-ray exam is still a privilege for
billions of people around the world. In this paper, we ask: "Can we develop a
low-cost sensing system that enables dental self-examination in the comfort of
one's home?"
  This paper presents ToMoBrush, a dental health sensing system that explores
using off-the-shelf sonic toothbrushes for dental condition detection. Our
solution leverages the fact that a sonic toothbrush produces rich acoustic
signals when in contact with teeth, which contain important information about
each tooth's status. ToMoBrush extracts tooth resonance signatures from the
acoustic signals to characterize varied dental health conditions of the teeth.
We evaluate ToMoBrush on 19 participants and dental-standard models for
detecting common dental problems including caries, calculus, and food
impaction, achieving a detection ROC-AUC of 0.90, 0.83, and 0.88 respectively.
Interviews with dental experts validate ToMoBrush's potential in enhancing
at-home dental healthcare.
