Ozone is a gas made of three atoms of oxygen with cyclic structure. We can get it from pure oxygen which is passing through high voltage area, and for medical purposes it is used as a mixture of gases containing 95% of oxygen minimum and 5% of ozone at the most. Ozone is an unstable gas that cannot be stored and should be used at once because it has a very short half-life. Ozone is used in many fields, such as industry, household and medicine. In dental medicine, dew to large capability of antimicrobial effect, is used in branches such as parodontology, oral surgery, dental pathology, oral medicine and other. In my final work I suggested two devices that are commercially used at the moment, Prozone and OzonyTrone, and mentioned their characteristics, work mode and advances of that kind of therapy. I have also made an overwiev of available literature considering ozone, and tried to briefly sum up and enclose what recent scientific work had discovered so doctors of dental medicine could have firm evidence and make an easier choice in order to buy and start practicing this kind of additional therapy. Researches speak about positive antimicrobial effects of ozone, but they are different depending whether it is used as a gas, ozonated water or ozonated oil. Most of the scientists, besides its positive effects, stand out the need of additional researches of ozone as an antiseptic in a parodontitis therapy.