Objectives: Dental cavities are a prevalent issue that, if untreated, can escalate into severe complications. Minimally invasive treatments, such as fissure sealants, have been developed to prevent early-stage cavities from progressing. Traditional sealants, however, often fail due to moisture contamination during application. To address this, hydrophilic sealants were designed to perform effectively in moist environments. A critical determinant of their success is the ability to create a durable, tight seal along the edges. Methods: This study used 20 extracted, caries-free, sound molars, randomly divided into two groups: Group I (hydrophilic sealants) and Group II (flowable composites). Tooth sectioning was performed mesiodistally using a low-speed diamond cutting blade. The specimens were immersed in 1% methylene blue solution at room temperature for 24 hours to assess dye penetration and the microleakage was evaluated using a stereomicroscope following Ovrebo and Raadal guidelines (1990). Results: Hydrophilic sealants demonstrated superior performance in microleakage prevention, with a significantly higher number of samples scoring zero for dye penetration compared to flowable composites. Statistical analysis using the Mann-Whitney U test (p<0.05) confirmed that Group I exhibited less dye penetration, highlighting the enhanced sealing ability of hydrophilic sealants. Conclusion: Hydrophilic sealants exhibit better sealing efficacy and reduced microleakage compared to flowable composites, particularly under moist conditions. Their superior penetration and adaptability make them a promising option for long-lasting dental restorations. Future research should focus on larger sample sizes, long-term clinical performance and optimizing application techniques for diverse clinical scenarios.