Fluorescence spectroscopy of natural carious lesions

We report on the use of a blue laser diode to excite natural fluorescence from a range of dental samples. Sixty teeth with naturally occurring lesions were examined. The lesions were classified onvisual inspection as falling into three classes as shiny lesions, dull lesions and brown lesions. The resulting fluorescence was then examined using a fibre optically coupled spectrometer in a series ofwavelength bands. By examining the intensity ratios in the two wavelength bands 480-500nm and620 to 640nm we were able to classify the lesion types and thus provide a quantifiable measurementof lesion types. This method has application for detection of dental caries as well as demonstrating potential application to evaluate lesions which may represent different degrees of caries activity.