Comparative safety of various intracanal irrigation systems.

The objective of this project was to evaluate the safety of various intracanal irrigation systems by measuring the apical extrusion of irrigant. Twenty-two single canal, extracted mature teeth were instrumented and secured through the lid of a scintillation vial to collect apically extruded irrigant. A precision syringe pump delivered controlled amounts of irrigant at a constant flow. The irrigation systems used were EndoVac Micro and Macro Cannula, EndoActivator, manual irrigation with Max-I-Probe needle, Ultrasonic Needle Irrigation, and Rinsendo. Results were analyzed by using one-way analysis of variance with Scheffé test (P < .05). The EndoVac Micro and Macro cannulae groups did not extrude irrigant, and there was no statistically significant difference between these 2 groups and the EndoActivator group. Within the groups that produced extrusion, EndoActivator extruded statistically significantly less irrigant than Manual, Ultrasonic, and Reinsendo groups. There was no statistically significant difference among Manual, Ultrasonic, and Rinsendo groups. This study showed that the EndoVac did not extrude irrigant after deep intracanal delivery and suctioning the irrigant from the chamber to full working length. EndoActivator had a minimal, although statistically insignificant, amount of irrigant extruded out of the apex when delivering irrigant into the pulp chamber and placing the tip into the canal and initiating the sonic energy of the EndoActivator. Manual, Ultrasonic, and Rinsendo groups had significantly greater amount of extrusion compared with EndoVac and EndoActivator.