Method: The study compared the performance of traditional visual examination under white light to negative fluorescence using narrow band blue or green LED light, and broad band visible blue and green light, using quantitative light fluorescence (QLF) as a control. Smooth surfaces of 100 extracted teeth were scored for absence of fluorescence. Experimentally created WSL served as positive controls for mineral loss.
Result:
For the positive controls, there was a linear relationship between the extent of demineralisation and the QLF fluorescence change (DF) values. Violet and blue lights could detect mineral loss by the 2nd day of demineralisation, but not green lights. On extracted teeth, ultraviolet and blue light sources showed the highest sensitivity (54.7 - 66.9%), specificity (87.1 - 95.0%) and accuracy (74.8 - 78.2%), and green light the worst, with poor sensitivity (2.7 - 7.8%).
Conclusion: Blue and violet lights, particularly blue LED lights used for curing resins, when used with an appropriate filter, may provide a simple adjunct to conventional white light examination methods for the earlier detection of WSL