Unveiling the Calcium Hydroxide Impact: Comparison of Push-out Bond Strength in AHplus and ADseal Resin-based Endodontic Sealers

Objectives: This in vitro study aimed to evaluate effects of calcium hydroxide (Ca(OH) 2 ) on bond-strength of two resin-based endodontic sealers, AHplus and ADseal. In light of ADseal's recent introduction to the dental market and the absence of research on the effects of Ca(OH) 2 on its bonding strength to dentinal walls, our investigation sought to fill this gap in knowledge. Methods: : Root canals of 128 single-rooted teeth were prepared and randomly divided into two groups (n = 64): Control group without Ca(OH) 2 and experimental group with Ca(OH) 2 inside canals. After a week of keeping samples at 100% humidity and 37°C, Ca(OH) 2 was removed, and the samples were further subdivided into two subgroups (n = 32) for filling with AHplus sealer or ADseal sealer. Following another week of incubation, the samples were cut into 2mm thick plates and subjected to pressure. Maximum force was measured in Newton just before bond failure and calculated using push-out bond-strength in MPa. Results: : The results showed average bonding-strength of AHplus sealer in treatment group with Ca(OH) 2 was significantly lower than in group without Ca(OH) 2 (p-value=0.00). However, no significant was observed in the average bonding-strength between the control and treatment groups with Ca(OH) 2 in ADseal (p-value=0.36). Comparing control groups, the average bond strength of AHplus sealer was significantly higher than that of ADseal sealer (p-value=0.01). Interestingly, the average bonding-strength of ADseal Sealer in experimental group was significantly more than AHplus sealer (p-value=0.00). Conclusions: : This study highlights that the presence of Ca(OH) 2 decreases bonding-strength of AHplus sealer while it does not significantly affect the bond strength of ADseal sealers. These findings provide valuable insights into the interplay between calcium hydroxide and resin-based endodontic sealers, contributing to a deeper understanding of their performance and potential applications in clinical settings.