| abstract |
In one aspect, a system for detecting blood in an oral cavity during toothbrushing is disclosed. A toothbrush includes a sensor configured to emit first light at a first wavelength and second light at a second wavelength, and receive reflected portions of the light, the reflected portions having a first intensity and a second intensity, respectively. For each of a plurality of different times of a brushing session, a processor calculates a ratio of the first intensity to the second intensity. The processor identifies peaks in the ratio over the different times and, based on the number of peaks in the ratio, determines whether hemoglobin is present in the oral cavity. |