Quantitative Light-Induced Fluorescence

  • Baek-II KimEmail author


Quantitative Light Induced fluorescence (QLF) distinguishes between an initial caries lesion and sound teeth by assessing fluorescence loss. Visible blue light irradiating the teeth and reaching the dentinoenamel junction (DEJ) induces fluorescence. This mechanism results in light scatters inside a white spot 5–10 times more than that in normal enamel, thus the lesion appears darker than sound enamel. The fluorescence loss detected by QLF can be visualized as an image, and with specialized software it is possible to nondestructively quantify the physical characteristics of caries lesions as numerical values. Previous studies have found that ΔF, one of the QLF parameters is strongly correlated with lesion depth. The systems is also able to assess [AZ1] red fluorescence, which reflects bacterial activity calculated by delta R (ΔR, in %).


Dental plaque Dental caries Fluorescence Optical diagnosis Quantitative light-induced fluorescence (QLF) 


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of Preventive Dentistry and Public Oral HealthYonsei University College of DentistrySeoulRepublic of Korea

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