One reason why root canal treatment  is such a challenge is that it’s not just the root canals themselves that must be cleaned out and disinfected. There are also the miles of microscopic tubules that form dentin, the tooth’s middle layer of tissue – a perfect harbor for bacteria, fungi, and other pathogens.
That’s a big reason why those “biological” dentists who choose to do root canals incorporate ozone into their treatment. The idea is that ozone gas, a powerful disinfectant, can get into the tubules more thoroughly than conventional chemicals, while also reportedly being less toxic to oral cells.
Yet it’s not a panacea. As we’ve noted before ,
the tubules will always carry the DNA of any pathogens. Even if you saturated the inside of the tooth with ozone or could somehow autoclave the tooth 24/7 for a couple weeks, those traces would remain.
Now, a new review of the science  suggests that ozone may not actually be all that much better for endodontic disinfection.
Published last fall in the International Endodontic Journal, the review looked at 180 studies on ozone in root canal treatment, narrowing down to 8 that met the researchers’ criteria. Most were considered at low risk of bias, but only one was a random clinical trial. The others were lab studies.
Overall, the evidence showed that ozone actually reduced bacteria less than sodium hypochlorite (NaOCl), the most commonly used solution for disinfecting root canal teeth.
Nor did ozone seem to boost the effectiveness of NaOCl when the two were used together.
Although the selected studies have limitations, this review reached a satisfactory methodological quality and moderate evidence to provide important preliminary information regarding ozone therapy. As regards microbial load reduction for patients undergoing root canal treatment, ozone therapy has inferior results when compared with conventional chemomechanical techniques using NaOCl. As an adjunct during chemomechanical preparation, ozone intervention was ineffective in increasing the antimicrobial effect of NaOCl. Therefore, ozone is not indicated either to replace nor to complement the antimicrobial action of NaOCl.
Of course, this is all a non-issue if you avoid root canals altogether, which we generally recommend. While there are rare instances in which root canal treatment accompanied by active terrain management might be considered “the least worst option” for dealing with a severely decayed or damaged tooth, extraction is usually the safer bet, followed by tooth replacement with a partial or bridge. (Yes, one-tooth “pop-in” partials are an option.)
Always and ever, it depends on the individual and their unique health history and current health situation. One size does not fit all.