In vitro antiviral activity of stabilized chlorine dioxide containing oral care products

OBJECTIVE

To determine the in vitro antiviral activity of oral care products containing stabilized chlorine dioxide toward infectious viruses that harbor in the oral cavity. Specfically, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), SARS-CoV, human coronavirus (HCoV) 229E, influenza A (H3N2), rhinovirus type 14, adenovirus type 5, and herpes simplex virus (HSV) type 1 and 2 were examined.

METHODS

Validated in vitro suspension virucidal assays were used. Test product was mixed with the test virus for 30, 60, or 120 s, neutralized with sodium thiosulfate, serially diluted in dilution medium in a 96-well plate and incubated in a carbon dioxide incubator for 7 days. The 50% Tissue Culture Infectious Dose per milliliter was determined.

RESULTS

Two rinses, one oral spray and one fluoride toothpaste showed log reduction of severe acute respiratory syndrome coronavirus-2 ranging from 1.81 to 2.98 and of influenza A from 2.58 to 4.13, respectively, within 30 s of contact time; similar results were obtained at 60 s. Further, the Ultra Sensitive rinse showed 0.19, 0.75, 1.58, 1.75, 2.66, and 3.24 log reduction of severe acute respiratory syndrome coronavirus, human coronavirus 229E, rhinovirus type 14, adenovirus type 5, and herpes simplex virus type 1 and type 2, respectively, within 30 s of contact time.

CONCLUSION

Stabilized chlorine dioxide containing ClōSYS^® oral care products reduced the viral load of multiple viruses within 30 s. The results warrant further investigation for potential in vivo applications.

Effectiveness of a Novel Dentifrice Containing Stabilized Chlorine Dioxide, Sarkosyl, and Sodium Fluoride

This in vitro study evaluated the effectiveness of a novel dentifrice containing stabilized chlorine dioxide, sodium lauroyl sarcosinate (sarkosyl), and sodium fluoride in enhancing enamel fluoride uptake, remineralization, pellicle cleaning and inhibiting biofilm regrowth. Remineralization was measured by fluoride uptake and surface microhardness assessment tests. Artificial stains were removed and scored based on pellicle cleaning ratio. Biofilm regrowth was measured by counting colonies on the agar plates. All studies were conducted using bovine teeth specimens. The efficacy of Toothpaste C (CloSYS anticavity toothpaste) was compared with United States Pharmacopoeia Reference Dentifrice, Toothpaste B (discontinued CloSYS anticavity toothpaste formulation) and leading commercial toothpastes. The enamel fluoride uptake and remineralization by Toothpaste C was 96.1% to 303.3% and 38.0% to 102.4% higher than the tested toothpastes, respectively. The mean pellicle cleaning ratio of Toothpaste C was similar to American Dental Association Reference Material. Toothpaste C had a significant reduction in regrowth of the oral polymicrobial biofilm compared to the control. All tested toothpastes contained 0.24% sodium fluoride. Toothpaste C exhibited significantly superior performance towards fluoride uptake and remineralization compared to the tested toothpastes. Therefore, toothpaste ingredients other than sodium fluoride accounted for the enhanced fluoride uptake and remineralization.