The purpose of this study was to compare, in vitro, the sealing ability of Super EBA and a compomer, Dyract, as root-end filling materials. Forty-eight single-rooted human teeth were cleaned, shaped and obturated with gutta-percha. The root apices were resected and root-end cavities were prepared. Twenty teeth were retrofilled with Super EBA and Dyract; eight teeth served as positive and negative controls. Half of the teeth in each group were immersed in basic fuschin for 4 weeks, the other half for 12 weeks. The teeth were then embedded in resin, sectioned, and the maximum extent of dye penetration measured. Statistical analysis (ANOVA) did not reveal a significant difference between the two materials at 4 weeks. At 12 weeks, the extent of dye penetration was statistically significant with Super EBA leaking more than Dyract (P = 0.002). Moreover, the extent of the dye penetration was statistically significantly different for Super EBA between the 4- and 12-week groups (P = 0), whereas no such difference was found for Dyract. Thus, the sealing ability of Dyract was found to be better than Super EBA at 12 weeks.