In comparison with no ozone therapy, the ultrasonic and sonic activation of ozone led to diminished pain in people undergoing single-visit endodontics. The study authors aimed to investigate the effect of different application techniques of ozone on the incidence of postendodontic pain in people undergoing root canal therapy.

The study included 108 people having necrotic pulp in single-rooted teeth and apical periodontitis. Using 5.25% sodium hypochlorite and rotary nickel-titanium files, a standard single-visit endodontics protocol was followed.

Following shaping and cleaning, participants were randomly segregated to: (i) Group 1 (n = 21): Ozone therapy with no activation (NA); (ii) Group 2 (n = 22): Ozone therapy with manual dynamic activation (MDA); (iii) Group 3, (n = 21): Ozone therapy with passive ultrasonic activation (PUA);  (iv) Group 4 (n = 23): Ozone therapy with sonic activation (SA); and (v) Group 5 (n = 21): No ozone therapy (the control group).

With the aid of a visual analog scale (VAS), recording of patient levels of discomfort was done at six different time intervals. The comparison of  mean difference between the groups and time intervals was carried out utilizing a 2-way analysis of variance. This was followed by a post hoc Bonferroni test with the level of significance set at 5%.

The VAS scores were greatest for the control > NA > MDA > SA > PUA groups. A considerable reduction in pain VAS scores was witnessed in the SA and PUA groups when compared to the  MDA, NA, and control groups. The timewise comparison indicated a remarkable drop in VAS scores at all the time intervals. Thus, ozone therapy can remarkably control endodontic pain.