Materials and Methods: Sixty-six extracted human lower premolar teeth were instrumented to size F3 with ProTaper instruments. The teeth were divided into 3 groups and obturated with matched-taper single-cone, Thermafil and lateral condensation techniques. AH Plus was used as a sealer. Six teeth were used as positive and negative controls. A fluid filtration system was used to evaluate the apical seal. Measurements were made at 2-minute intervals for 8 minutes and the average of these values was recorded. One-way analysis of variance test was used for statistical analysis.

Results: Mean leakage values for the lateral condensation, single-cone and Thermafil groups were 0.49 ± 0.37 μL min^-1, 0.39 ± 0.24 μL min^-1 and 0.44 ± 0.25 μL min^-1, respectively. The difference between the groups was not statistically significant (p > 0.05).

Conclusions: The apical sealing ability of matched-taper single-cone obturation was comparable with that of lateral condensation and Thermafil techniques.