Periodontitis is a chronic multifactorial inflammatory disease associated with dysbiotic plaque biofilms and characterized by progressive destruction of the tooth-supporting apparatus, subsequently causing pocket formation, gingival recession or both. Ozone has been applied in medicine for more than a century now, although its clinical implications in dentistry have only been recently investigated. The beneficial biological effects of ozone, its anti-microbial activity, oxidation of bio-molecules precursors and microbial toxins implicated in periodontal diseases and its healing and tissue regeneration properties, make the use of ozone well indicated in all stages of periodontal diseases. Therefore, the use of ozone as an adjunctive therapy characterizes a novel method in the treatment of chronic periodontal disease.