Bond strength of different endodontic sealers to dentin: push-out test

objective: the aim of this in vitro study was to evaluate the bond strength of different root canal sealers to dentin. material and methods: forty extracted single-rooted human teeth were examined and the coronal and middle thirds of the canals were prepared with a 1.50 mm post drill (fibrekor post system, pentron). the teeth were allocated in two experimental groups, irrigated with 2.5% naocl+17% edta or saline solution (control group) and instrumented using race rotary files (fkg) to a size #40 at the working length. then, the groups were divided into four subgroups and filled with epiphany sealer (group 1), endorez (group 2), ah26 (group 3) and grossman's sealer (group 4). after 2 weeks of storage in 100% humidity at 37oc, all teeth were sectioned transversally into 2-mm-thick discs. push-out tests were performed at a cross-head speed of 1 mm/min using a universal testing machine. the maximum load at failure was recorded and expressed in mpa. results: means (±sd) in root canals irrigated with 2.5% naocl and 17% edta were: g1 (21.6±6.0), g2 (15.2±3.7), g3 (14.6±4.5) and g4 (11.7±4.1).two-way anova and tukey's test showed the highest bond strength for the epiphany's group (p< 0.01) when compared to the other tested sealers. saline solution decreased the values of bond-strength (p<0.05) for all sealers. conclusion: epiphany sealer presented higher bond strength values to dentin in both irrigating protocols, and the use of 2.5% naocl and 17% edta increased the bond strength values for all sealers.