According to the Environmental Protection Agency (EPA) in the U.S., ozone is a highly reactive gas composed of three oxygen atoms (O3). As the EPA goes on to tell us, ozone can be good or bad. The so-called "ozone layer" in the stratosphere is important because it reduces harmful UV radiation from reaching us on the Earth's surface. But this good layer of ozone is presumably being depleted by man-made chemicals.
The bad ozone, on the other hand, is created at ground level mainly by pollution from emissions of industrial facilities, vehicle exhausts, etc. Our health can be adversely affected by this bad ozone, which can trigger respiratory problems by reducing pulmonary function. It can also damage vegetation that can affect agricultural production and the landscape of recreational areas such as parks and forests.
So if the ozone closest to us can be a threat to our health and environment, why are we even discussing its use in dentistry? The answer is in its property of being, perhaps, the most powerful oxidant and antimicrobial agent. This is true whether it is used by itself as a gas or added under pressure in water. In fact, it reportedly has much higher disinfection capabilities compared to chlorine and doesn't produce harmful decomposition products. This is why ozonators, for example, are being used to reduce the amount of chlorine in swimming pools and spas. It is also being used by the bottled water industry to disinfect water before we drink it and has now been approved by the FDA to treat food. In addition, the FDA has recently approved an ozone sterilizer that can also inactivate prions.
What's more, there is even evidence that deadly methicillin-resistant Staph aureus (MRSA) infections can be prevented and maybe even treated with ozonated water. Another use of ozonated water being proposed is for sinus irrigation, which could offer tremendous relief to millions who suffer from difficult to treat sinus infections.
With this short background, you can see why ozone has been adapted for use in dentistry. The most prolific researcher in this field is one of our own Editorial Team Members, Dr. Edward Lynch. He has been investigating how best to use ozone in dentistry for many years and has helped bring the first, commercially viable ozone device on the market in most areas of the world, except notably the U.S., where it still awaits approval by the FDA.