Impact of Ultrasonic Activation on the Effectiveness of Sodium Hypochlorite: A Review

Using ultrasonic devices in endodontics can enhance the antibacterial and tissue dissolving ability of different root canal irrigants such as sodium hypochlorite (NaOCl) which is the most common irrigant with excellent antibacterial and tissue dissolving abilities. However, due to its high surface tension, its penetration into the irregularities of the root canal system is a challenge. The purpose of this paper was to review the different ultrasonic devices, different types of ultrasonic irrigation, the effect(s) of ultrasonic activation on the antibacterial and biofilm-removal abilities of NaOCl as well as the effect of ultrasonic activation on the smear layer removal ability of NaOCl.