Comparative fluorescence spectroscopy shows differences in noncavitated enamel lesions

Area of Science:

• Dental Research
• Biophotonics
• Spectroscopy

Background:

• Dental caries detection often relies on visual inspection, which can be subjective.
• Non-cavitated enamel caries present diagnostic challenges.
• Understanding the optical properties of early caries is crucial for improved diagnostics.

Purpose of the Study:

• To compare emission spectra of non-cavitated enamel caries with varying discoloration levels.
• To investigate the effect of different excitation wavelengths on caries fluorescence.
• To analyze spectral shifts and fluorescence bands in carious versus sound enamel.

Main Methods:

• Human molars with white spot, light, and dark brown spot enamel caries were analyzed.
• Emission spectra were recorded using fluorescence spectrophotometry across excitation wavelengths (360-580 nm).
• Spectra from carious and sound enamel areas were compared after normalization.

Main Results:

• All carious lesions showed a red shift in emission spectra compared to sound enamel.
• The red shift was significantly greater for dark brown spot lesions than white spot lesions (p
• Porphyrin-like fluorescence bands (600-700 nm) were observed, strongest at 400-420 nm excitation.

Conclusions:

• Enamel discoloration in caries correlates with significant spectral shifts.
• Fluorescence spectroscopy can differentiate between sound and carious enamel based on spectral characteristics.
• The findings support the potential of fluorescence techniques for early caries detection.