Low-Viscosity Resin Infiltration Efficacy on Postorthodontic White Spot Lesions: A Quantitative Light-Induced Fluorescence Evaluation.

Objective: The aim of this study was to evaluate the efficacy of low-viscosity light-cured resin infiltration on postorthodontic white spot lesions (WSLs) on incipient and advanced lesions using quantitative light-induced fluorescence (QLF).

Methods: The study subjects were patients with clinically diagnosed postorthodontic WSLs (n=57). QLF images of the lesions were obtained using a QLF device (Inspektor-Pro, Amsterdam, The Netherlands) before any treatment. Images were processed using the built-in software (QLF patient v2.0.0.48), which produced fluorescence loss (ΔF), lesion area (Area), and impact (ΔF x Area, ΔQ) values. Lesions were categorized as incipient (-5<ΔF<-12, n=14) or advanced (-12<ΔF<-25, n=43). They were then infiltrated with low-viscosity resin (Icon-DMG, Hamburg, Germany) according to the manufacturer's instructions. QLF imaging was repeated (ΔF, Area, and ΔQ) from the same aspects assured by the relative software. Kolmogorov-Smirnov, Wilcoxon, and Mann-Whitney tests were used for data evaluation.

Results: ΔF (-8.40±0.73) and Area (3.44±5.19) decreased to -6.58±0.88 and 0.18±0.33 for incipient lesions (p<0.001 and p=0.002, respectively). ΔF (-13.20±5.32) and Area (4.71±5.56) decreased to -7.51±2.7 and 0.29±1.86 for advanced lesions (p<0.001). When ΔF, lesion area, and ΔQ changes between the groups were compared, the decrease in ΔF was greater for advanced lesions (p<0.001), whereas the decrease in the lesion area and ΔQ was similar (p=0.690, p=0.291).

Conclusions: Infiltration treatment provides improvement of WSLs in terms of fluorescence loss, lesion area, and impact for both incipient and advanced lesions, with the latter group presenting higher fluorescence loss reduction.