Real-time intracanal temperature measurement comparing mechanically and laser-activated irrigation to syringe irrigation.

ABSTRACT

Antibacterial activity and tissue dilution of sodium hypochlorite (NaOCl) are improved by moderately heating the irrigant. Temperature can be risen by preheating or intracanal activation. To assess intracanal temperature development of NaOCl during irrigation activation and syringe activation (SI) in a closed system at 37°C, Type-K thermocouples were inserted close to the root canal of one human single-rooted maxillary canine at the apex and 5 and 10 mm from the apical foramen via drilled holes. The root was positioned in a plastic vial filled with alginate simulating surrounding biological structures. Experiments were performed in a closed environment at 37°C (n = 14) EA EndoActivator (Dentsply Sirona), EDDY EDDY (VDW), PUI passive ultrasonic irrigation, PIPS Photon-induced photoacoustic streaming (Fotona), S60 SI of 60°C-NaOCl, S45 SI of 45°C-NaOCl, and S20 SI of 20°C-NaOCl. S45, PUI and EDDY lead to minor intracanal temperature increases. EA and PIPS did not influence the intracanal temperature. SI with 60°C-NaOCl resulted in higher intracanal temperatures than activation systems. Temperature dissipation into simulated tissues buffered intracanal temperature changes.