The retreatment of teeth obturated with bioceramic sealers has been shown to be challenging.
The purpose of this study was to compare the efficacy of 10% formic acid (FA), 20%
hydrochloric acid (HCl), and chloroform for achieving patency in teeth obturated with
a bioceramic sealer.
Forty-five extracted single-canal teeth were instrumented and obturated 1.5 mm short
of the working length using gutta-percha and EndoSequence BC Sealer (Brasseler USA,
Savannah, GA). Two weeks later, gutta-percha was removed, and apical patency was attempted
with a 10 C-file and a solvent (FA, HCl, or chloroform). The time to gain patency
through EndoSequence BC Sealer was recorded. Five additional teeth were irrigated
with the solvents, and scanning electron microscopy was used to evaluate the effect
of solvents on the dentin. The Kruskal-Wallis and Mann-Whitney tests were used for
Patency was achieved in all canals, except for 1 in the chloroform group. Regarding
the time to achieve patency, no significant difference was noted between chloroform
and FA (P > .05). However, there was a significant difference between chloroform and HCl (P < .05) and between FA and HCl (P < .05). The erosion of dentinal tubules was more evident when HCl was used compared
with the other irrigants.
Twenty percent HCl was superior to 10% FA and chloroform in achieving patency in teeth
obturated with EndoSequence BC Sealer. Regardless of the solvent used, patency may
be achieved for most of the cases obturated with gutta-percha and EndoSequence BC