Sealing ability and adaptability of three materials namely; Dyract eXtra, ProRoot MTA and BioAggregate were evaluated in repair of small and large furcation perforations immediately and after one month. One hundred and sixteen extracted human mandibular molars were divided into experimental groups (108 teeth) and control groups (8 teeth). For sealability evaluation, dye leakage was tested from an orthograde direction and dye extraction was performed using nitric acid (65% wt). Dye absorbance was measured at 550 nm using spectrophotometer. For adaptability evaluation, SEM was used to evaluate the interface between the repair materials and perforation margins. Regarding sealability evaluation, Dyract showed the least leakage in both small and large perforation specimens at both evaluation periods. Size of perforation and also evaluation period showed no statistically significant difference. Regarding adaptability results, Dyract eXtra showed superior adaptation compared to MTA and BioAggregate in both immediately evaluated small and large perforation specimens and also specimens evaluated after one month. It was concluded that Dyract eXtra showed good sealability and adaptability immediately and after one month. Marginal integrity at the interface appeared to deteriorate over time.