The aim of the study was to evaluate the regional push-out bond strength of mineral trioxide aggregate (MTA) after exposure to sodium hypochlorite (NaOCl), ethylenediaminetetraacetic (EDTA), and peracetic acid (PAA) irrigation solutions.Materials and Methods:
1-mm-thick longitudinal slabs of root dentin were obtained from freshly extracted human canine teeth (n = 80). Simulated root perforation defects, 1 mm in diameter, were prepared in the coronal, middle, and apical thirds of radicular dentin. Mineral trioxide aggregate was placed into the cavities, and the specimens were stored for 1 week at 37°C. Thereafter, the specimens were randomly divided into four groups (n = 20) according to the irrigation solution applied over the repair sites: Group 1–10 ml of 5.25% NaOCl for 10 min; Group 2–10 ml of 5.25% NaOCl for 10 min, followed by 5 ml 17% EDTA for 5 min; Group 3–10 ml of 5.25% NaOCl for 10 min, followed by application of 5 ml 1% PAA for 5 min; and Group 4–no irrigation. Push-out test was performed at a crosshead speed of 1 mm/min. Debonding values were compared statistically using two-way analysis of variance and Tukey tests (P < 0.05).Results:
The push-out bond strength of MTA was not affected by the type of irrigation solution or location of the perforation defects (both P < 0.05). Stereomicroscopic inspection of the samples showed that the bond failure was predominantly adhesive.Conclusion:
Exposure of repaired root perforations to 5.25% NaOCl, 17% EDTA, or 1% PAA does not alter the dislocation resistance of MTA at different locations of root dentin.