In vitro ability of a laser fluorescence device in quantifying approximal caries lesions in primary molars

Abstract Objectives This in vitro study aimed at evaluating the ability of Laser Fluorescence device (LFpen) in quantifying approximal caries lesions in primary molars. Methods Two examiners assessed 123 approximal surfaces of primary molars using the DIAGNOdent pen (LFpen). Surfaces were determined to be either sound with white-spot lesions or have small cavitations. After sectioning, lesion depth was determined through polarized light microscopy. The intra-/inter-examiner agreement was calculated using intraclass correlation coefficient (ICC) and Bland–Altman analyses. Furthermore, Spearman correlation coefficients ( R s) were calculated between LFpen readings and lesion depth. Results Correlation between LFpen values and lesion depth was low for both examiners ( R s = 0.36 and 0.51), especially when cavitated lesions were excluded from the analysis ( R s = 0.22 and 0.40). For all surfaces, ICC revealed intra- and inter-examiner reproducibility values of 0.75 and 0.63, respectively, but when only non-cavitated surfaces were analyzed, these values decreased (0.41 and 0.33, respectively). Conclusions LFpen readings present low correlation with approximal caries lesion depth and low reproducibility, especially in white-spot lesions. Therefore, the device could not be a suitable method for monitoring non-cavitated approximal caries lesion in primary molars.