To detect an initial-stage carious tooth in a subsurface demineralization state where the intensity of fluorescence radiated from a carious part is extremely small compared to that from a healthy part.
This carious tooth detecting apparatus is provided with an irradiation means 10 for irradiating a tooth with light of a predetermined wavelength, a filter 14 for sorting out the wavelengths of light radiated from the tooth, an imaging means 15 for converting the light transmitting through the filter into electric signals, and an image display means 16 for displaying the state of the tooth from the imaging means as image information. The filter cuts out wavelength components of the irradiation light of the irradiation means 10 to remove reflected light of the irradiation wavelength and transmit only the fluorescence excited to a long wavelength side by the irradiation light out of the lights radiated from the tooth with the initial-stage carious part. This constitution displays the initial-stage carious part having the extremely small intensity of the fluorescence compared with that of the healthy part as a dark spot on the image so as to detect the initial-stage carious part.
Tomoyasu Sakaguchi
Hiroki Naito