Influence of Light Curing and Potassium Iodide Application on the Color Change in SDF-Treated Dentin Surfaces

This study investigated the effect of combining silver diamine fluoride (SDF) with potassium iodide (KI) and light curing on the color change in artificially induced dentin carious lesions of primary teeth. Fifty extracted primary second molars were demineralized to induce artificial caries and divided into 5 groups: Group I (distilled water for 60 seconds), Group II (SDF for 60 seconds), Group III (SDF for 60 seconds and KI for 10 seconds), Group IV (SDF for 10 seconds and light curing for 3 seconds), and Group V (SDF for 10 seconds, KI for 10 s and light curing for 3 seconds). Color measurements were recorded before (T0), immediately after (T1), and 4 weeks after (T2) treatment. Color differences (ΔE*ab) and L*a*b* values were compared between time points within each group. Groups III and V, showed no significant differences in ΔE*ab values between T0 - T1 and T0 - T2, regardless of light curing. Between Groups IV and V (both with light curing), Group V showed significantly lower ΔE*ab and ΔL* values, indicating that KI reduced staining under light-cured conditions (p < 0.005). Intra-group comparisons revealed that color change in the groups with light curing mainly occurred immediately after treatment (T0 - T1), whereas in the groups without light curing, greater changes occurred during the subsequent 4 weeks (T1 - T2, p < 0.05). These findings suggest that combining SDF with KI is effective in reducing black discoloration, even under light curing. This approach may offer a time-efficient and esthetically favorable treatment option for pediatric patients with limited cooperation.