Apical seal using the GPII method in straight canals compared with lateral condensation, with or without sealer

The purpose of this study was to test the apical seal provided by a recently introduced low-fusing gutta-percha, GPII, compared with lateral condensation, with or without a sealer. For this study, 84 roots with straight circular canals separated from extracted teeth were prepared to K-file size 45. A standardized gutta-percha master cone was fitted to 80 of these roots. The roots were then randomly separated into four groups of 20 each and filled with GPII or laterally condensed gutta-percha, with or without AH26 sealer. The roots were immersed in India ink, subjected to vaccuum for 2 hours and kept in the marker for 4 days for the study of apical leakage. Four unfilled roots served as an experimental control. The teeth were demineralized, cleared in methyl salicylate and examined with a stereomicroscope. When no sealer was used, 12 roots filled with GPII leaked from 0 to 2.5 mm and in the lateral condensation group ink penetrated from 0 to 6 mm in 14 roots (difference not significant at the 0.05 level). None of the specimens in which sealer was used showed any penetration of ink beyond the end of the preparation of the canal regardless of the filling technique.