A recent randomized clinical trial published in the International Endodontic Journal found that the use of Ultrasonically (UAI) and laser‐activated irrigation (LAI) lead to comparable levels of post‐operative pain relief in patients receiving primary root canal treatment.

A total of 56 patients with an asymptomatic tooth requiring primary root canal treatment were registered to distinguish between the efficacy of UAI and LAI in terms of pain relief. The teeth were randomly designated to 2 groups- UAI group and LAI group, with 28 patients in each group.  Patients were blinded to the final irrigation protocol. After root canal, the patients recorded the pain intensity at different time intervals i.e. 6, 24, 48 and 72 hours on visual analogue scale (VAS). The use of  analgesics was also noted.

After the root canal surgery, low pain intensity was observed, with many patients having no or minimal pain a day after the surgery. The pain intensity and incidence were considerably higher in the UAI group than the LAI group at 6 hours. No difference was found concerning the use of analgesics in both the groups. No adverse effects were found.