Evaluation of microleakage and remineralization potential of a fissure sealant containing microcapsules on artificial enamel lesions: with and without adhesive application.

Within the concept of minimal invasive dentistry, the progression of initial caries lesions can be inhibited with preventive measures. This study evaluated the microleakage and remineralization potential of a bioactive fissure sealant (FS) on artificial caries lesions. For microleakage assessment, 40 extracted human molars were demineralized and randomly assigned to four groups (n = 10). Specimens were sealed with either bioactive FS (BioCoat®; Premier Dental Co, USA) or a conventional resin-based FS (Clinpro™; 3 M ESPE, USA), with half of each group pretreated with a universal adhesive system. After thermocycling, microleakage was evaluated using a dye penetration test. For remineralization analysis, 10 molars were divided into BioCoat and Clinpro groups (n = 5 each). Four standardized windows were prepared on each tooth to represent sound enamel, demineralized enamel, and demineralized enamel treated with either sealant, with or without prior adhesive application. After a 30-day dynamic pH cycling process, Scanning Electron Microscopy / Energy Dispersive X-ray Spectroscopy (SEM/EDX) was performed at depths of 0, 5, 10, 15 and 20 μm from the outer enamel surface toward dentin. Microleakage scores were analyzed using the chi-square test, while SEM/EDX measurements were evaluated using the Kruskal-Wallis test and repeated-measures ANOVA (p < 0.05). No significant differences in microleakage were observed between the bioactive and conventional FS groups. SEM/EDX analysis demonstrated greater mineral-related changes across the evaluated depths in the bioactive FS group, with increased Ca, P, and F levels (p < 0.001). In contrast, the conventional FS showed limited remineralization at depths of 0 and 5 μm (p < 0.05). The use of an adhesive system under FS did not significantly influence microleakage or remineralization. These findings suggest that bioactive fissure sealants may enhance enamel remineralization in initial caries lesions more effectively than conventional sealants. However, further clinical studies are required to support these findings.