Bond Strength of Experimental Root Canal Sealers Based on MTA and Butyl Ethylene Glycol Disalicylate.

This study investigated the bond strength of two experimental root canal sealers based on MTA and butyl ethylene glycol disalicylate: MTAe and MTAe-HA. The reference materials used for comparison were AH Plus and MTA Fillapex. Twenty human upper incisors were selected and one 1 mm slice was obtained from the cervical third of each root. On the coronal surface of each slice, four 0.9 mm wide holes were drilled through the dentine. Standardized irrigation was performed and holes were filled with one of the four tested sealers: AH Plus, MTA Fillapex, MTAe, and MTAe-HA. The filled slices were stored in a PBS solution (pH 7.2) for 7 days at 37 °C. A push-out assessment was performed with a 0.7 mm plunger tip. Load was applied at a crosshead speed of 0.5 mm/min until sealer displacement. The results were expressed in MPa. The Kruskal-Wallis test was applied to assess the effect of each sealer on the push-out bond strength. Mann-Whitney with Bonferroni correction was used to isolate the differences. The alpha-type error was set at 0.05. Significant differences among medians values obtained by materials were observed (p<0.001). AH Plus displayed the highest value of bond strength (p<0.001). In contrast, MTA Fillapex presented the lowest bond strength among all tested sealers (p<0.001). Experimental sealers showed intermediary bond strength values, with no statistical differences between them (p>0.05). In conclusion, experimental root canal sealers presented suitable bond strength outcomes when compared to MTA Fillapex.