Spectral fluorescence imaging for quantitative diagnosis and mapping of dental fluorosis affected tooth surfaces

A new analytical method for quantitative diagnosis of dental fluorosis is suggested. The method is based on the spectral modifications in the fluorescence light emitted from affected enamel surfaces, relative to normal dental enamel. Imaging of the tooth surface is obtained using an imaging Fourier transform fluorescence spectrophotometer. This technique provides simultaneous fluorescence spectra at all pixels of the examined area. Images and the corresponding spectra were acquired at various tooth regions, and it was shown that normal, white opaque, brown discolored, and pitted tooth surfaces have different distinct spectral features which characterize the different degrees of the observed pathology of dental fluorosis. Criteria for quantitative assessment of the dental fluorosis stages were suggested. These were based on the measured spectral emission ratio at two wavelengths and comparison with the spectrum of normal enamel. The suggested parameters were validated against clinical observation of numerous samples affected by dental fluorosis at various pathological stages. Besides the introduction of the quantitative assessment, the method is suggested for detection of early changes in the characteristics of the tooth surface in dental fluorosis. The associated mapping capability allows for morphological characterization, which provides additional important clinical information.