practical prophylaxis | Yvonne Hoffmann: In 2014, Hoffmann Dental took over Proxidentis Dentale Biomaterialien, a producer of natural oral health products, including ozone oil for periodontal treatment. After learning about ozone oil, it was only a small step towards developing ozone water rinses. What are the differences in application between ozone as a gas mixture and ozone dissolved in water? Viebahn-Hänsler: Gaseous ozone cannot possibly act as a disinfectant. Owing to its polar molecular structure, ozone has great solubility in a polar solvent like water. As hydrogen bonds stabilise ozone, ozone’s half-life in water by far exceeds that of its gaseous version. As such, we recommend ozone water or oil for disinfecting wounds, not an ozone–oxygen gas mixture. Moreover, the gas mixture cannot be used safely in dentistry owing its toxicity to the respiratory epithelium. Ozone water, however, can be used as a mouthwash to rinse wounds and periodontal pockets. Owing to its pronounced dis- infectant and healing effects, ozone is a perfect alter- native to tooth cleaning with sugar alcohols or sodium bicarbonate. Ozone water must be generated on-site. Is training necessary? Viebahn-Hänsler: Our ozone water generator is subject to the Medical Device Act and requires instruction and training by a medical device consultant. Nonetheless, its handling is very simple. How does ozone inhibit anaerobic periodonto-patho- genic bacteria? What advantages does it have over conventional periodontal treatment? Hoffmann: Rinsing with ozone water followed by the application of ozone oil is a great complement to con- ventional periodontal treatment or professional dental cleaning. Viebahn-Hänsler: Ozone water does not distinguish between aerobic and anaerobic bacteria. It destroys the cell membrane and ultimately the DNA/RNA of bacteria and viruses that come into direct contact with the ozone molecules. Additionally, ozone water improves healing processes by activating the cellular metabolism. Hoffmann: Ozone oil works differently in that it only kills anaerobic bacteria, which are the bacteria specifi- cally linked to periodontal disease. Because of its den- sity, ozone oil easily adheres to interdental spaces and periodontal pockets, where it is retained for longer than ozone water. Unlike chlorhexidine, ozone water and ozone oil in excessive amounts cannot possibly lead to altered taste or tooth discoloration. They do not provoke any allergies, have no known side-effects and are a safe, effective Dr Renate Viebahn-Hänsler Yvonne Hoffmann way to reduce the postoperative use of antibiotics and cortisone. What are the benefits of ozone beyond dentistry? Is it used elsewhere? Viebahn-Hänsler: Medical ozone is used for wound disinfection and treating chronic inflammatory diseases. Other therapeutic applications are auto-haemotherapy, in which the patient’s blood is exposed to ozone and then reinjected, or rectal insufflation. Hoffmann: Ozone is also used in water purification in municipal waterworks to destroy bacteria and para- sites such as Cryptosporidium and Giardia. Unnoticed by most of us, it is also used in public swimming pools to reduce the total chlorine level needed to improve the water quality. prevention 1 2018 67