Comparison of fluorescence detection of carious dentin for different excitation wavelengths.

This study compared the fluorescence spectra obtained at three laser excitation wavelengths from intact enamel, sound dentin and carious dentin. Results were analyzed using a figure of merit (ratio of backscattered peak to maximum fluorescence amplitude). The results showed that the best excitation wavelengths for caries detection, which offered the greatest contrast between sound and carious tissue, were 442 and 632 nm. A discussion of the results between these two ends of the visible spectrum is provided. The results confirmed the choice of red light as a good excitation source for fluorescence detection of caries.