Application of quantitative light-induced fluorescence technology in early caries detection and resin infiltration treatment.

Objectives: The aim of this study is to explore the specific application scenarios of quantitative light-induced fluorescence (QLF) in the detection and treatment of early caries, so as to provide more evidence for the clinical application of QLF.

Methods: (1) The accuracy of QLF in detecting the lesion depth of early caries was evaluated by combining transverse microradiography (TMR) and spectrophotometer analysis (n=6). (2) Resin infiltration therapy was used as a representative method for the treatment of early caries to evaluate the ability of QLF in assessing the therapeutic effect on early caries (n=6). (3) Re-demineralization of early caries after treatment was performed to evaluate the detection capability of QLF for deeper lesions (n=6).

Results: In the detection of early caries, when the demineralization depth < 200 µm, both QLF and spectrophotometer analysis were accurate and correlated well with TMR results (r=-0.9938, r=-0.9534, p < 0.05). In addition, both QLF and spectrophotometer detection could effectively reflect the therapeutic effect on early caries after resin infiltration treatment. However, when the early caries treated with infiltrative resin were re-demineralized and the lesion depth > 200 µm, the diagnostic accuracy of QLF for the re-demineralized early caries decreased significantly, which was not as precise as TMR and spectrophotometer analysis.

Conclusion: When the demineralization depth is less than 200 µm, QLF can be used to detect early caries and evaluate the therapeutic effect on early caries. However, QLF is not suitable for detecting deep re-demineralized lesions exceeds 200 μm after resin infiltration treatment.

Clinical Significance: Timely diagnosis and treatment of early caries are very important in clinic. Exploring the specific applicability of QLF in the detection and treatment on early caries is helpful to provide more evidence for its clinical application, which is of great significance for the prevention and treatment of caries.