Objective: The aim of the study was to compare microleakage and marginal adaptation of White Mineral Trioxide Aggregate (WMTA), Biodentine and chemical-cured glass ionomer cement (GIC) as root-end filling materials using the dye extraction method and scanning electron microscope (SEM). Materials and Methods: The study used 90 extracted human mandibular premolar teeth. After the instrumentation and obturation of root canals, the apical 3 mm of the roots were resected perpendicular to their long axes. Root-end cavities were prepared using diamond-coated ultrasonic retrotips. Samples were divided into three experimental groups according to the root-end filling material used (n = 30): WMTA, Biodentine, and EQUIA-Fil GIC. Each group was subdivided into two sub-groups A and B. Samples in sub-group A were evaluated for microleakage using the dye extraction method, while those in sub-group B were evaluated for marginal adaptation using SEM. The obtained results were analysed statistically using ANOVA and Tukey tests. The significance level was set at 5% (P ≤ 0.05). Results: WMTA had the lowest mean dye absorbance value and the smallest interfacial gap width followed by Biodentine and EQUIA-GIC, with no significant difference between them. Conclusion: WMTA, Biodentine and chemical-cured GIC demonstrated comparable sealing ability as root-end filling materials. Schlagwörter: Biodentine, glass ionomer cement, Mineral Trioxide Aggregate, periapical surgery, tricalcium silicate