In vitro evaluation of bacterial leakage resistance of an ultrasonically placed mineral trioxide aggregate orthograde apical plug in teeth with wide open apexes: a preliminary study

Objective: The purpose of this study was to compare the sealing ability of an ultrasonically placed orthograde mineral trioxide aggregate (MTA) apical plug in open apices. Study design: Thirty extracted human maxillary incisors were used. Experimental teeth were instrumented up to #100 file at the apex, and the 5 mm MTA apical barrier was placed with (group A; n = 11) or without (group B; n = 11) ultrasonic activation. Eight teeth served as control group. Bacterial leakage was assessed daily for 180 days using a double-chamber bacterial leakage model with Enterococcus faecalis. The results were analyzed with Fisher exact test. Results: After 60 days, the ratio of leaked samples showed significant difference between groups A (2 out of 10) and B (8 out of 11) (P < .05). The mean time elapsed before leakage showed significant difference between groups A (158 days) and B (23 days) (P < .05). Conclusions: Ultrasonically placed orthograde MTA apical plugs were effective at delaying bacterial leakage.