Ineffectiveness of ozone therapy in nonsurgical periodontal treatment: a systematic review and metaanalysis of randomized clinical trials.

This systematic review (SR) aimed at assessing the adjunctive clinical effect of ozone therapy (OT) on nonsurgical periodontal treatment. Articles published prior to September 2019 were electronically searched in four databases without any other date or language restrictions and manually searched in regular journals and in gray literature. This review was performed according to the PICO format. The eligibility criteria comprised randomized controlled trials (RCTs) that analyzed the adjunctive effect of OT on nonsurgical periodontal treatment. Twelve studies published between 2010 and 2019 were included in this SR. A metaanalysis of ten reports showed that there was no statistically significant difference in the periodontal parameters analyzed when scaling and root planing (SRP) plus sulcus irrigation with ozonated water or sulcus insertion of ozonated gas were used when compared to SRP alone. Additionally, there was no significant difference when the effect of SRP plus ozonated water was compared with SRP plus 2% chlorhexidine gluconate (CLX). No studies reported significant microbiological differences when the use of ozone was compared with SRP alone. The results of this SR do not support the use of OT for nonsurgical periodontal treatment. However, due to the potential heterogeneity across the studies, the presence of confounding factors, and the short follow-up of some included RCTs, these results should not be considered definitive. The current evidence indicates that ozone has antimicrobial activity and good biocompatibility with periodontal cells and gingival fibroblasts. However, no evidence was found for a positive effect of OT as an adjunct to scaling and root planing.