Can nasal irrigation with chlorine dioxide be considered as a potential alternative therapy for respiratory infectious diseases? The example of COVID-19.

Chlorine dioxide (ClO2) is a high-level disinfectant that is safe and widely used for sterilization. Due to the limitations on preparing a stable solution, direct use of ClO2 in the human body is limited. Nasal irrigation is an alternative therapy used to treat respiratory infectious diseases. This study briefly summarizes the available evidence regarding the safety/efficacy of directly using ClO2 on the human body as well as the approach of nasal irrigation to treat COVID-19. Based on the available information, as well as a preliminary experiment that comprehensively evaluated the efficacy and safety of ClO2, 25-50 ppm was deemed to be an appropriate concentration of ClO2 for nasal irrigation to treat COVID-19. This finding requires further verification. Nasal irrigation with ClO2 can be considered as a potential alternative therapy to treat respiratory infectious diseases, and COVID-19 in particular.

Comparative evaluation of antiplaque and antigingivitis effects of an herbal and chlorine dioxide mouthwashes: A clinicomicrobiological study.

AIM: The aim of the present study was to compare the efficacy of herbal mouthwash and chlorine dioxide mouthwash in reduction of plaque and gingivitis. SETTINGS AND DESIGN: In a randomized clinical trial, forty patients were randomly selected and divided equally into two groups. MATERIALS AND METHODS: After professional oral prophylaxis, the clinical parameters plaque index, gingival index, and modified sulcular bleeding index were recorded at baseline, 7th day, 14th day, and 21st day. The plaque samples were collected from gingival sulcus with an absorbent sterile paper point and were stored in a thioglycollate broth, then sent for microbiological examination. The microbial colony-forming units were assessed at baseline, 7th day, 14th day, and 21st day for Streptococcus mutans, Tannerella forsythia, and Fusobacterium nucleatum. RESULTS: There was a statistical significant reduction in both clinical and microbiological parameters were observed with use of both the mouthwashes. However, herbal mouthwash was more effective in reducing the plaque and gingivitis than chlorine dioxide mouthwash. CONCLUSION: Herbal mouthwash was statistically efficacious in controlling plaque and gingivitis with potent antimicrobial activity.

The whitening effect of chlorine dioxide--an in vitro study.

OBJECTIVES: The aim of this study was to investigate the whitening properties and rate of bleaching action of chlorine dioxide and compare them with those of hydrogen peroxide of similar concentration. METHODS: Sixty bovine central incisor crowns were ground and polished until flat surfaces were obtained. The crowns were subjected to extensive staining cycles of artificial saliva, chlorehexidine and tea before being randomly assigned to three groups: chlorine dioxide (ClO2), hydrogen peroxide (H2O2) and deionised water (H2O). The crowns in each group were subjected to seven 2 min exposure cycles in addition to an extra 30 min cycle. CIE LAB spectrophotometric measurements were taken at baseline, after each 2 min, and each extended 30 min bleaching cycle. RESULTS: L* for ClO2 specimens was significantly higher only after the first 2 min cycle (p<0.001) while for H2O2 specimens, L* significantly increased after the first two cycles (p<0.001) and continued to increase, at a slower rate, until the end of the treatment cycles. ΔE was significantly greater within H2O2 than within ClO2 specimens (p<0.001). CONCLUSION: Chlorine dioxide whitens teeth at a faster rate than hydrogen peroxide. Specimens treated with chlorine dioxide were significantly lighter than those treated with hydrogen peroxide at the end of the first 2 min application cycle, however, extended exposures did not enhance color.

The efficacy of a continuous-use stabilized chlorine dioxide dental unit waterline cleaner and the evaluation of two water sampling methods.

Many commercial dental unit waterline cleaners are available. Results regarding the efficacy of these products vary and sampling methods and laboratory procedures can affect results. This study was conducted to test the efficacy of a continuous-use stabilized chlorine dioxide product and determine if two different sampling methods produced the same results. There was a statistically significant difference between the treated units and the control units (p < 0.05) but the two sampling methods revealed no statistically significant difference (p > 0.5). Treated units showed a decline in the mean number of colony forming units per milliliter (CFU/mL) over the study period but the level was not consistently low enough to meet the ADA-recommended levels of 200 CFU/mL. The findings of this study indicate that it is not necessary to replace a continuous use product with fresh, untreated water when testing water quality.

The effect of four mouthrinses on oral malodor.

The purpose of the study was to compare the efficacy of four mouthrinses in clinical outcomes of changes in oral malodor measurements in a 4-week, randomized, double-blind, longitudinal clinical trial in adults. The four rinses were coded as Products 1, 2, 3, and 4 so that neither the examiners nor subjects had the knowledge of treatment. Of the four mouthrinses, two were commercially available mouthrinses with essential oils (EO) or chlorine dioxide plus zinc (CD/Zn) as active ingredients (Products 1 and 4), one mouthrinse was a formulation containing cetylpyridinium chloride (Product 2), and one was a placebo (Product 3). A total of 99 subjects who met the study criteria were assigned randomly to one of the four groups. At three separate visits (0, 2, and 4 weeks), subjects received an examination of the oral soft tissues and were assessed for baseline oral malodor by two organoleptic judges and a laboratory instrument that measures oral malodor. Subjects were instructed to use the assigned rinse, and the measurements were performed again after 2 and 4 hours. Throughout the 4-week study period, each subject was asked to use the assigned rinse twice daily per the manufacturer's recommended directions. The results showed that the four mouthrinses reduced oral malodor within 4 hours after a single usage, with Product 2 being the most effective and the placebo being the least effective. Daily use of EO, CD/Zn, and placebo rinses for up to 4 weeks did not reduce oral malodor from week 0 baseline values, and the effects on oral malodor were comparable among these three mouthrinses. Product 2 was the only mouthrinse that reduced oral malodor from baseline values after 2 and 4 weeks of daily use.

A multifactorial investigation of the ability of oral health care products (OHCPs) to alleviate oral malodour.

UNLABELLED: AIM, BACKGROUND: Oral malodour (halitosis) is generally ascribable to oral microbial putrefaction generating malodorous volatile sulphur compounds which predominantly comprise dihydrogen sulphide and methyl mercaptan. This study assesses the relative effectiveness of 6 oral health care products in reducing oral cavity volatile sulphur compound concentrations. METHOD: A mixed model 3-factor factorial experimental design involving 6 volunteers, 7 treatment regimens (products I-VI* and water placebo) and 5 time-points (0.00-5.29 h) was undertaken. Electron-donating volatile sulphur compound levels were determined in triplicate using a sulphide monitor (Interscan model 1170) both prior to (0.00 h) and following oral rinsing (20 ml of 5 of the products) or chewing (2 capsules of the remaining product) episodes with each product examined (0.29, 1.29, 2.29 and 5.29 h post-administration). RESULTS: Results were recorded as peak and steady-state volatile sulphur compound equivalents (ppb). With the exception of one of the products, each oral health care product tested was found to reproducibly reduce volatile sulphur compound concentrations within 20 min of treatment; the mean % decreases in peak (and corresponding steady-state) levels ranging from 3.6 (0.0) to 16.8 (16.4)%. Subsequently, volatile sulphur compound concentrations returned to their zero-control (baseline) values within 5 h, the rate of this regression being in the reverse of the order observed for the magnitude of the primary 20 min reduction for both peak and steady-state measurements. As expected, the water placebo exerted no influence on oral cavity volatile sulphur compound levels. The most effective oral health care products contained admixtures of chlorite anion and chlorine dioxide (both of these agents have the ability to directly oxidise volatile sulphur compounds to non-malodorous products and the latter is also powerfully cidal towards odourigenic micro-organisms). CONCLUSIONS: We therefore conclude that oral health care products containing such oxohalogen oxidants may provide a useful therapeutic strategy for the treatment of oral malodour.