Impact of adhesive layer addition on the optical properties of remineralized white spot lesions

The present in vitro study evaluated the camouflage effect of two treatments for white spot lesions (WSLs): remineralization with Mi Paste Plus© (GC Europe N.V.) and remineralization combined with a Scotchbond Multi-Purpose© (3M ESPE 2015) adhesive layer. Additionally, the study assessed the color stability of the treatments when exposed to a staining agent, such as coffee.

Sixty extracted anterior and posterior teeth were preserved in saline solution and divided into two groups. Artificial WSLs were created using 37% orthophosphoric acid for 1 minute. Both groups underwent daily 6-hour remineralization treatments with Mi Paste Plus© for 14 days. In the second group, a thin adhesive layer was applied after remineralization. Color analysis was performed using an MHT SpectroShade Micro spectrophotometer at baseline (T₁), after remineralization (T₂), after adhesive application for group 2 (T_R), and after immersion in coffee for 24 hours (T₃). Color differences (ΔE) between healthy tissue and WSLs were assessed, with ΔE≤3.3 considered clinically acceptable. Data were analyzed using STATA 17 (P≤0.05).

ΔE analysis showed a statistically significant improvement in the camouflage effect in the adhesive-treated group (T_R) compared to remineralization alone (T₂). After coffee exposure (T₃), ΔE values increased significantly in both groups, with higher values observed in the adhesive-treated group. Intragroup analyses indicated significant differences between T₂ and T₃, as well as T_R and T₃.

The application of an adhesive system can be considered a valid option to improve the aesthetic outcome of a remineralization treatment; however, this approach carries the risk of resin staining over time.