An in vitro comparison of quantitative light-induced fluorescence-digital and spectrophotometer on monitoring artificial white spot lesions

Purpose: The aim of this study was to evaluate the efficacy of quantitative light-induced fluorescence-digital (QLF-D) compared to a spectrophotometer in monitoring progression of enamel lesions. Methods: To generate artificial caries with various severities of lesion depths, twenty bovine specimens were immersed in demineralizing solution for 40 days. During the production of the lesions, repeat measurements of fluorescence loss (δF) and color change (δ. E) were performed in six distinct stages after the demineralization of the specimens: after 3, 5, 10, 20, 30, and 40 days of exposure to the demineralizing solution. Changes in the δF values in the lesions were analyzed using the QLF-D, and changes in the δ. E values in lesions were analyzed using a spectrophotometer. The repeated measures ANOVA of δF and δ. E values were used to determine whether there are significant differences at different exposure times in the demineralizing solution. Spearman's rank correlation coefficient was analyzed between δF and δ. E. Results and conclusion: The δF values significantly decreased based on the demineralizing period (p<0.001). Relatively large changes in δF values were observed during the first 10 days. There were significant changes in L^*, a^*, b^*, and δE values in lesions with increasing demineralizing duration (p<0.001). A strong correlation was observed between δF and δE with p=-0.853 (p<0.001). The results support the efficacy of QLF-D in monitoring color changes. Our findings demonstrate that QLF-D are a more efficient and stable tool for early caries detection.