Aesthetic caries infiltration - Long-term masking efficacy after 6 years

This study aimed to evaluate the masking efficacy of caries infiltration technique of initial caries lesions (ICL) six years after debonding and single treatment.

In 10 adolescents, 74 ICL (ICDAS 2) in 74 teeth were treated by resin infiltration (Icon, DMG) at a mean (SD) of 1.2 (1.2) months after bracket removal. The etching procedure was performed up to 3 times. Standardized digital images were taken before treatment (T₀), seven days (T₇) and 6 years (T₂₁₉₀) after treatment. Outcomes included the evaluation of the color differences between carious and healthy enamel at T₀, T₇ and T₂₁₉₀ by quantitative colorimetric analysis (ΔE), ICDAS scores, quantitative light-induced fluorescence (QLF; ΔF,ΔQ,WS Area) and qualitative visual evaluation (5-point Likert-scale [deteriorated (1), unchanged (2), improved, but not satisfying (3), improved and no further treatment required (4), completely masked (5)).

The median color difference ΔΕ₀ (25^th/75^th percentiles) at T₀ was 10.3 (8.56/13.0). At T₇ a significant decrease was observed (ΔΕ₇=3.7 (2.0/5.8); p<0.001; Friedmann-test; ICDAS p<0.001; Chi-square test). No significant changes based on ΔΕ (p=0.972; Friedmann-test) and ICDAS grading (p=0.511, chi-square test) were observed between T₇ and T₂₁₉₀ (ΔΕ₂₁₉₀=2.9 (1.8/4.2)). Furthermore, at T₂₁₉₀ four experienced dentists classified 50% and 37% of the lesions as "improved and no further treatment required" and "completely masked", respectively (Fleiss kappa: T₂₁₉₀: 0.782 (substantial agreement)).

Aesthetic caries infiltration can effectively mask post-orthodontic initial caries lesions for at least 6 years. These results for most of the teeth could not only be observed by quantitative but also by qualitative analysis.

Resin infiltration efficaciously masks post-orthodontic initial carious lesions. The optical improvement can be observed directly after treatment and remains stable for at least six years.