Lesion activity assessment of early caries using dye-enhanced quantitative light-induced fluorescence

Seok Woo Park, Si Mook Kang, Hyung Suk Lee, Sang Kyeom Kim, Eun Song Lee, Bo Ra Kim, Elbert de Josselin de Jong, Baek Il Kim

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We aimed to determine whether dye-enhanced quantitative light-induced fluorescence (DEQLF), wherein porous structure of caries lesions is stained with a fluorescent dye, could quantitatively distinguish between active and inactive caries. A total of 126 bovine specimens were prepared to artificially simulate caries activity. Active caries were demineralized with 1% carbopol solution for 3 (A3), 5 (A5), and 10 days (A10). For inactive caries, half specimens in each group were remineralized with 2% NaF and reallocated into three groups (I3, I5, and I10, respectively). Wet specimens were dried with compressed air for 10 s and then dyed with 100-µM sodium fluorescein for 10 s. Fluorescence images of speicmens were captured with a QLF-digital 2 + Biluminator. Fluorescence intensity (ΔG) was measured in fluorescence images of dyed specimens. ΔG between active and inactive groups was compared using independent t-test, and ΔG among active groups (or inactive groups) were compared using ANOVA (α = 0.05). ΔG in the active groups was 33.7–59.0 higher than that in the inactive groups (P < 0.001). Except between I3 and I5, there was significant differences in ΔG according to the demineralization period (P < 0.001). DEQLF might be used to evaluate early caries activity, and longitudinally monitor changes in lesion activity.

Original languageEnglish
Article number11848
JournalScientific reports
Issue number1
Publication statusPublished - 2022 Dec

Bibliographical note

Funding Information:
This research was supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant number: HI20C0129) and by a grant of the Bio & Medical Technology Development Program of the National Research Foundation (NRF) & funded by the Korean government (MSIT) (No. 2022M3A9F3016364).

Funding Information:
Inspektor Research Systems BV provided the salary for author EdJdJ, but it did not have any role in the study design, data collection, analysis, decision to publish, or preparation of the manuscript. EdJdJ’s involvement in this research was under the auspices of his status as adjunct professor at Yonsei University College of Dentistry supported by BK21 FOUR Project. The specific role of EdJdJ was to provide his expertise regarding the fluorescence technology. This does not alter the author’s adherence to the policies of Scientific Reports on sharing data and materials. EdJdJ holds several patents with respect to QLF technology. The remaining authors declared no conflicts of interest.

Publisher Copyright:
© 2022, The Author(s).

All Science Journal Classification (ASJC) codes

  • General


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