RESUMO
The aim of this study was to evaluate the ability of Obtura II (Obtura Spartan, Fenton, MO) and Calamus (Densply, Tulsa, OK) to fill artificially created lateral canals in simulated plastic teeth using standard gutta-percha, Flow 150 gutta-percha (Obtura Spartan, Fenton, MO), and Resilon (Resilon Research, LLC, North Branford, CT). Lateral canals were created at 2, 4, 6, 8, 10, and 12 mm from the apex in plastic teeth. The teeth were divided into eight groups. In group 1, teeth were filled with a single increment of Calamus; in group 2, canals were filled with Calamus in three increments. In group 3, Obtura II was used with a single increment of standard gutta-percha, whereas in group 4 Obtura II was used in three increments. Groups 5 and 6 were similarly filled as in the preceding groups. A multiple-comparison analysis of variance test followed by a Tukey post-hoc test were used to compare filling material penetration into the lateral canals and the experimental groups (p < 0.05). The results indicated that the flow of the filling material into lateral canals is a function of the viscoelastic properties of the filling material rather than the mechanical properties of the delivery systems. Our data also suggest that the Resilon filling material flows better into lateral canals when a single backfill technique is used.