Effect of Irrigants on the Push-Out Bond Strength of Three Bioceramic Root Repair Materials: An In Vitro Comparative Analysis

Aims: This study aims to comparatively assess the impact of root canal irrigants on the push-out bond strength (POBS) of mineral trioxide aggregate (MTA), biodentine, and EndoSequence root repair material (ERRM). Materials and Methods: In this in vitro study, the midroot dentin of human canine teeth was sectioned horizontally into slices of 1.5 mm thick. The canal lumen of each dentin slice was then enlarged to a diameter of 1.3 mm using a No. 5 GG drill. One hundred and twenty samples were then randomly split into three groups (n = 40), and the following materials were filled into the canal space, respectively: ProRoot MTA, biodentine, and ERRM putty. The samples were covered with damp gauze for 10 min. They were subsequently divided into four subgroups (n = 10) to be immersed in 3% sodium hypochlorite, saline, 2% chlorhexidine gluconate, and no irrigant (control), respectively. After incubation for 48 h, the POBS of the samples was determined using a universal testing machine. A stereomicroscopic examination of the samples was done to ascertain the nature of the bond failures. One-way ANOVA was employed to assess the differences in POBS among the three materials when exposed to different irrigants and pairwise comparison was done using post hoc Tukey test. The significance level was set to P < 0.05. Results: ERRM demonstrated the highest POBS of 6.83 +/- 0.94 MPa when tested with normal saline and ProRoot MTA recorded the lowest POBS of 3.44 +/- 0.47 MPa under chlorhexidine. Under saline, both ERRM and biodentine showed a significantly better (P < 0.05) POBS value than ProRoot MTA. With NaOCl, ERRM showed a significantly better (P < 0.05) POBS value than ProRoot MTA and biodentine. With chlorhexidine, both ERRM and biodentine showed significantly better results (P < 0.05) as compared to ProRoot MTA. Conclusions: ERRM showed the highest POBS value irrespective of the irrigant used, whereas ProRoot MTA showed the least. This suggests that ERRM may be the preferred choice for root repair, especially when using chlorhexidine as an irrigant.