Periodontitis is an inflammatory disease that is initiated by distinct oral pathogens that populate dental plaque biofilms on the tooth surface resulting in damage of tooth supporting structure. The aim of the periodontal therapy is to arrest infection, restore the lost structure and maintain a healthy periodontium. Ozone has a powerful oxidation effect with significant antimicrobial potential.It can inhibit bacterial proliferation, upregulate cellular antioxidant enzymes, enhance the release of growth factors and local oxygen supply and promote hemostasis. This prospective split mouth randomized case control study was conducted in 10 systemically healthy patients with pocket depth of >5mm on at least two teeth in each quadrant of maxilla/mandible. Selected quadrants were randomized using coin toss method into 2 groups