Gas Chromatography – A Sensitive Tool for Assessing Malodour Management

Methods: These were blinded, randomised, crossover studies with 16 (study A) or 20 (study B) healthy volunteers between the ages of 19-54. Study A: breath samples were collected at baseline, immediately and 1hr after brushing. Four dentifrices (Zinc A, Zinc B, a commercially-available dentifrice and Control) were evaluated. Study B: breath samples were collected at baseline, immediately, 1, 2, 3 and 7 hours after treatment. Subjects consumed a defined breakfast then provided an additional breath sample between baseline assessment and treatment. Two dentifrices (gel-to-foam and a commercially-available dentifrice) were evaluated. Breath samples were collected using a 20 ml syringe and were analysed for VSCs (hydrogen sulphide, methyl mercaptan and Total VSCs) utilising gas chromatography (GC) with flame photometric detection.

Results: Study A: immediately after treatment, a statistically significant reduction in VSCs from baseline was observed for Zinc A product only. A statistically significant reduction in VSCs from baseline was observed after 1 hour for all products. Both zinc products exhibited a significantly greater reduction from baseline VSCs than the commercially-available dentifrice and Control at all time points. Study B: a statistically significant reduction in VSCs from baseline was observed at all time points for both products. The gel-to-foam product exhibited significantly greater reduction from baseline Total VSC concentration than the commercially-available dentifrice at all time points from 1 hour post-treatment.

Conclusion: Control of oral malodour by toothpaste treatment, evaluated as VSC levels using GC, has been demonstrated. Zinc is effective at reducing VSCs and the efficacy of zinc is formulation dependent. A gel to foam dentifrice was more effective at controlling VSC levels than a commercially-available dentifrice up to 7 hours.