In vitro effect of propolis and ۲% chlorhexidine as intracanal medicaments on push-out bond strength of fiber post cemented with resin cement

Background: This study assessed the effect of propolis and ۲% chlorhexidine (CHX) on push-out bond strength of fibre post-cemented with resin cement.Materials and Methods: This in-vitro, experimental study evaluated ۳۶ extracted human mandibular premolars in three groups (n=۱۲). After root canal cleaning and shaping, propolis and ۲% CHX gel were applied as an intracanal medicament in groups ۱ and ۲, respectively. Group ۳ received no medicament. The access cavity was sealed, and the teeth were incubated for one week. The root canals were obturated and post space was prepared using the #۲ Angelus drill. After ۷۲ h of incubation, the crowns were cut, and the roots were mounted in acrylic and incubated for one week. The roots were sectioned into apical, middle and coronal thirds and underwent a push-out test. Data were analyzed using ANOVA and Bonferroni and Tukey’s tests. Results: The propolis group showed maximum and minimum bond strength in the middle and coronal thirds, respectively (P>۰.۰۵). The CHX group showed the highest and the minimum bond strength in the coronal and middle thirds, respectively (P>۰.۰۵). The control group showed maximum and minimum bond strength in the middle and coronal thirds, respectively (P>۰.۰۵). The mean bond strength in the propolis group was significantly higher than the control group (P<۰.۰۵). Conclusion: using propolis as intracanal medicament can increase the push-out bond strength of fibre post-cemented with resin cement in the middle third of the root while using CHX increases the push-out bond strength of fibre post in the coronal third.