Drying protocol influence on the bond strength and apical sealing of three different endodontic sealers

The aim of this study was to evaluate the influence of drying protocols (DP) on the apical sealing (AS) and on the bond strength (BS) of teeth filled with different sealers. The root canals of one hundred and fifty-six roots of maxillary canines were prepared with Reciproc rotary files (R50). The teeth were randomly divided into four groups (n = 39), according to the DP: GI-paper points; GII-70% isopropyl alcohol + aspiration with NaviTip points; GIII-95% ethanol + paper points; GIV-EndoVac + paper points. Each group was divided into subgroups, according to the sealer used: AH Plus, Sealapex and MTA Fillapex, using a single-cone technique. Evaluation of AS and BS was performed with fluid filtration (FF) and push-out (PO) methods, respectively. The PO test consisted of sectioning the roots, and subjecting a single slice from each third to testing and analysis for failure type. The data was submitted to two-way and three-way variance analysis (ANOVA) and Tukey (α = 5%). The AS showed no drying protocol influence. The FF results revealed a statistically significant difference between MTA and Sealapex (p < 0.05) sealers. The BS test values showed that there was no statistical significant difference among the canal thirds (p > 0.05), but that there was such a difference among the sealers (p < 0.05), among the protocols (p < 0.05), and in the interaction between sealers and protocols (p < 0.05). AH Plus revealed the highest BS values among the sealers; the highest BS results for the sealers occurred with the specimens used with isopropyl alcohol, compared with ethanol and EndoVac.