Penetration of Universal Adhesive System after Smear Layer Removal on Dentin Using Tamarindus indica Solution

Background: The smear layer causes a weak bond to dentin; therefore, removal of the smear layer with ethylenediamine tetraacetic acid (EDTA) solution was recommended. EDTA can cause erosion and changes in dentin’s microhardness. Hence, natural products that are biocompatible and have fewer side effects are being developed, one of which is Tamarindus indica. Tamarindus indica solution contains organic acids (citric acid, acetic acid, and maleic acid), therefore, it can dissolve minerals (demineralization), remove the smear layer, and act as a chelating agent. Objective: To compare the penetration of the universal adhesive system after smear layer removal on dentin using Tamarindus indica 2,5%, 5%, 10%, and 17% EDTA solution. Methods: Premolars (n=24) had their enamel removed, exposing the dentin. Four groups of smear layer removal agents, Tamarindus indica 2,5%, 5%, 10%, and 17% EDTA were applied to dentin. A universal adhesive system was then applied, restored with composite resin, and incubated at 37° for 24 hours. Penetration of the universal adhesive system was observed using a Scanning Electron Microscope. Results: There was a significant difference in the penetration of universal adhesive after smear layer removal between Tamarindus indica 10% group and Tamarindus indica 2.5%, 5%, and EDTA 17% group (p <0.05). The longest resin tag penetration was found in Tamarindus indica 10% compared to Tamarindus indica 2,5%, 5%, and EDTA 17%. Conclusion: 10% Tamarindus indica solution was effective in the removal of the smear layer and resulted in longer penetration of resin tags compared to 2.5% Tamarindus indica, 5% Tamarindus indica, and 17% EDTA.