Aesthetic Management of Artificially-Induced Stained-Remineralized Dental Caries Lesions

Objectives: Non-invasive aesthetic treatment options for stained arrested caries lesions have not been explored. This study aimed to develop laboratory models to create stained-remineralized caries-like lesions (s-RCLs), based on metallic/non-metallic stains, and to test the efficacy of bleaching on the aesthetic treatment of the created lesions.
Methods: Human dental specimens (enamel and dentin) were embedded in acrylic blocks, and their color was measured spectrophotometrically at baseline and after demineralization. Specimens were randomly divided into 4 groups (n=14) based on the tested staining/remineralization protocols for a total of 5 days: G1: control (no staining/no remineralization); G2: no staining/remineralization in artificial saliva (AS); G3: non-metallic staining/AS; G4: metallic staining/AS. The mineral loss (ΔZ) and lesion depth (L) were measured using transversal microradiography (TMR) along with color change (ΔE). Specimens were subjected to bleaching and color was re-evaluated. Color change and TMR outcomes were analyzed using ANOVA models followed by Fisher’s PLSD tests (α=0.05).
Results: For both enamel and dentin, s-RCLs in stained groups (G3 and G4) were darker than non-stained groups (G1 and G2), with G4 being darker than G3 (all p<0.001). s-RCLs in G2, G3 and G4 showed significantly lower ΔZ and L than G1 (all p<0.001), indicating their remineralized status. G4 had significantly lower ΔZ and L (better remineralization) compared to G2 (p<0.001). Bleaching treatment was more effective (p<0.001) in non-metallic compared to metallic-stained lesions regardless of the type of substrate.
Conclusions: The proposed models created distinct simulated s-RCLs. Non-metallic stained lesions were lighter and more responsive to bleaching compared to metallic stained lesions.