Antimicrobial activity of various ‘active’ gutta‐percha points against Enterococcus faecalis in simulated root canals

AbstractAim  To test the antimicrobial activity of various gutta‐percha points against Enterococcus faecalis in simulated root canals.Methodology  Root canals were simulated by inoculated glass capillaries. A 2.5 μL increment of a suspension of E. faecalis was placed into 10 simulated root canals together with Calcium HydroxideR points (CHP), Calcium Hydroxide PlusR points (CH+P), active pointsR (AP), conventional gutta‐percha points (CP) (Coltène Whaledent, Langenau, Germany) or no points (NP) (control) (each n = 2). The points and simulated root canals were flushed with 2 mL of sterile saline solution after 10 min or after 5 h of anaerobic incubation (37 °C, 100% humidity). Dilution sequences until 10−3 and 10−4 were prepared and plated on agar plates. The original suspension, diluted until 10−6 and 10−7, served as another control. The numbers of colony forming units were counted after 24 h. This experimental procedure was repeated 15 times.Results  Without gutta‐percha points, bacteria grew threefold in number within 5 h. With CHP and CH+P bacterial counts at 10 min and 5 h were approximately 50% compared with the control. AP killed all bacteria within 5 h. With CP, bacteria proliferated more than without points (counts at 5 h 177% of NP). Except for CHP versus CH+P differences between groups were statistically significant (Mann–Whitney test, P < 0.01).Conclusions  In this experimental model, the potential of CHP and CH+P to kill E. faecalis was limited. CP stimulated bacterial growth. AP killed all bacteria after 5 h.