Introduction: The aim of this study was to evaluate the effect of different final irrigation activation techniques affect the bond strength of self-expanding Smart-Seal obturation at the different thirds of root canal space.
Materials and methods: One hundred single-rooted human teeth were prepared using the Pro-Taper system to size F3, and a final irrigation regimen using 3% sodium hypochlorite and 17% EDTA was performed. The specimens were randomly divided into five groups (n = 20) according to the final irrigation activation technique used as follows: No activation (control), manual dynamic activation (MDA), CanalBrush activation, ultrasonic activation (UA) and EndoActivator. Five specimens from each group were subjected to scanning electron microscopic observation for assessment of the smear layer removal after the final irrigation procedures. All remaining roots were then obturated with Smart-Seal obturation system. A push-out test was used to measure the bond strength between the root canal dentin and Smart-Seal paste. The data obtained from the push-out test were analyzed using two-way analysis of variance and Tukey post-hoc tests.
Conclusions: It was observed that UA improved the bond strength of Smart-Seal obturation in the coronal and middle third and MDA/EndoActivator in the apical third of the root canal space.
Keywords: Push-out bond strength; Smart-Seal system; self-expanding.