Title	Ozone Gas Application on Oral Biofilm Does Not Effectively Arrest or Kill Bacteria Associated with Dental Caries
Clinical Question	In patients with dental caries, does gaseous ozone therapy significantly reduce or eradicate the responsible bacteria in oral biofilm compared to lesions that receive no treatment?
Clinical Bottom Line	When applied as a gas to an active carious lesion, ozone therapy does not significantly arrest or eradicate the bacteria responsible for producing dental caries when compared to active carious lesions that receive no treatment. Many studies that were reviewed show a high risk of bias and inconsistent methods to conclusively demonstrate that ozone therapy is effective in arresting dental caries or is a cost-effective method in which to treat dental caries.
Best Evidence
PubMed ID Author / Year Patient Group Study type (level of evidence) 15266519 Rickard/2004 3 studies including 137 people, with 432 pit and fissure caries or primary root caries lesions (PRCLs) Systematic review of randomized trials Key results The three trials included in this systematic review all measured caries by Electric Caries Monitor (ECM) and Diagnodent. Baseline of clinical severity index changes, determined by these two factors, demonstrated no advantage from ozone therapy in any of the included studies. Follow up was completed at least 6 months after treatment. 16707073 Brazzelli/2006 10 studies including 287 people, with 768 carious lesions (pit and fissure caries and PRCLs) Systematic review of randomized trials Key results Participants ranged from ages 7 to 82. Follow-up periods ranged from 6 to 21 months. In the included studies, ozone therapy was always used in combination with another active treatment (including reductant, reductant plus patient care kit, sealant, and reductant with sealant) and then compared to the same treatment without ozone therapy. The main outcome measure of the included studies was caries reversal, and was determined by carious lesions becoming hard or reversing from “leathery” to “leathery approaching hard texture.” It was reported that PRCLs with ozone therapy showed improvement in becoming hard and becoming less severe, and were less likely, if at all, to become soft when compared to control PRCLs.
Evidence Search	(Dental Caries/therapy*[MeSH Terms]) AND Ozone/therapeutic use*[MeSH Terms]
Comments on The Evidence	All three trials included in Rickard/2004 were determined to have a high risk of bias. This is due to the fact that participants were not masked, the same operator provided all studied treatments and outcome assessments in the same visit, and no power calculations were included. High bias such as this makes the results questionable, thus still not giving reliable evidence that ozone treatment is more effective than no treatment in treating dental caries. The review also states that the analyses were conducted only at the level of the lesion and were not independent of the person, therefore making the analysis inappropriate. Due to pooling not being attempted in the included studies, any differences that are defined as “significant” should be viewed with caution. Data was also not provided in any study for future conventional treatment needed. Techniques used to assess extent of carious lesions must demonstrate that they can be reproducible, reliable, sensitive, and specific, as de- and re-mineralization of carious lesions has proven to be constantly changing. In the included studies, none of the diagnostic methods were standard in current dental practices. Moreover, in the three studies included in Rickard/2004, no numerical values were provided in the ozone output used by HealOzone units used for ozone therapy. The reductant and its contents used as a co-therapy were also not specified, lacking detail in what was being used in the control groups. This review states that there is lack of evidence as far as optimal ozone output/concentration for therapeutic levels, duration of application, and duration of therapeutic effects, how far therapeutic effects penetrate into enamel and/or dentin structure, or side effects that may be endured due to ozone application to carious lesions. It therefore states that ozone therapy should not be considered as an alternative to accepted dental caries treatments. It is instead recommended that better known therapies, such as topical fluoride application and sealants, be utilized to prevent and treat dental caries. In Brazzelli/2006, for two of the included studies, some P-values were reported p < 0.001. However, no statistical analyses were provided. No information was provided on validity or reproducibility of severity index made or clinical identifications of “leathery,” “soft,” or “hard.” In one study, results compared at different follow-up points showed inconsistencies in data collection. Overall, the studies claimed that high success rates were reported for non-cavitated root caries, while simultaneously claiming that root caries were not reversed using conventional methods, such as reductant. Cavitated root lesions did not appear to benefit from ozone therapy. For pit and fissure caries in another included study, the mean change from baseline in clinical severity was not significant between ozone plus reductant therapy versus only reductant therapy (p = 0.112). It was also reported that a greater number of ozone-treated lesions stabilized compared to control lesions; however, no statistical analyses of these sets of data were provided. Relationships for classifications such as “clinical severity score” and “need for future fillings” were not explained in the studies. in a pilot study by the same author P-values ranged from <0.05 (for Hardness Index and Visual Index), 0.084 (Colour Index), and 0.16 (Perceived Treatment Needed). P-values were not analyzed as “paired data” on a patient basis, therefore “validity and reliability are open to question” (16). Abstracts included in this review gave limited detail as to the methodology used and thus results “should be interpreted with caution”. Both of these systematic reviews appeared highly critical of the results, noting inconsistencies and unaccepted methods in collecting data, lack of statistical analyses being reported, lack of information regarding reproducibility or validity, and inability to explain clinical identifiers such as “leathery,” “soft,” or “hard,” or classifications such as “clinical severity score” or “need for future fillings.” The Brazzelli review also notes the inconsistency in data stating that caries were not effectively arrested by fluoride application, although it has been long been established that topical fluoride is clinically effective in doing so. The studies are cautious in accepting that ozone therapy is readily an available alternative to treating dental caries when its therapeutic doses, side effects, ability to penetrate, and other critical information are still unknown following these studies. Dental professionals ought to be suspicious of quick fix therapies such as these, especially when they are being advertised as successful when so much information regarding their effectiveness and side effects is still unknown. Until reproducible and valid methods can be used to determine ozone therapy success, with quantifiable numbers of ozone output, statistical analyses of results, and low bias, gaseous ozone therapy should not be advertised as effective in arresting or eliminating the bacteria responsible for dental caries.
Applicability	The ability to kill the bacteria responsible for dental caries without the use of anesthesia or rotary instruments (hand pieces) is a novel idea and of interest to dental professionals and patients alike. If a more efficient, less destructive way of eradicating dental caries is available, many in the dental field may want to utilize this treatment.
Specialty	(General Dentistry) (Restorative Dentistry)
Keywords	Ozone therapy, oral biofilm, caries, dental caries
ID#	3271
Date of submission	11/13/2017
E-mail	caroline.stern@ucdenver.edu
Author	Caroline Stern
Co-author(s)
Co-author(s) e-mail
Faculty mentor	Ethelyn Thomason, DMD
Faculty mentor e-mail	Ethelyn.ThomasonLarsen@ucdenver.edu
Basic Science Rationale (Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?) None available
Comments and Evidence-Based Updates on the CAT (FOR PRACTICING DENTISTS', FACULTY, RESIDENTS and/or STUDENTS COMMENTS ON PUBLISHED CATs) None available