Epigallocatechin‐Gallate Methacrylate as a Novel Addition to Pit and Fissure Sealants: An In Vitro Analysis of Physical Properties and Microscopy

To enhance the longevity of resin sealants on the occlusal surfaces of posterior teeth, improvements are needed in antibacterial properties, mechanical resistance, and bond strength to enamel. This study investigated the effectiveness of incorporating epigallocatechin-gallate methacrylate (EGCG-M) into a pit and fissure sealant (SEAL, PacSeal) by assessing its penetration depth, degree of conversion, color properties, and surface morphology. Thirty blocks of bovine enamel were divided into three groups: SEAL (control), SEAL with neat EGCG (E0), and SEAL with EGCG-M. Analyses were conducted including penetration depth with confocal microscopy, degree of conversion using FTIR-ATR, color analysis using CIELab, and surface morphology via 3D laser microscope. The EGCG-M group exhibited the highest degree of conversion (44.9% ± 2.1%) compared to the SEAL (41.7% ± 2.1%) and E0 (42.1% ± 1.1%) groups (p = 0.040). Deeper penetration was observed in the EGCG-M group (9.7 ± 10 μm), followed by SEAL (-0.1 ± 12.2 μm) and E0 (-5.3 ± 9.7 μm) groups (p = 0.002). Although no significant difference was found in L* (lightness) coordinate values between the groups (p = 0.060), the EGCG-M group exhibited a more heterogeneous surface. Therefore, incorporating EGCG methacrylate into the sealant improved the degree of conversion and penetration capability without notable changes in color.