The effects of dentifrice systems on oral malodor

Chronic oral malodor is a serious concern for about one-fifth of the North American population, and a field of emerging research interest. The present three studies, one involving gas chromatography and two employing odor jud ge assessment, examined the efficacy of baking soda and other toothpastes i n reducing breath odor. The most common cause of oral malodor is elevated l evels of volatile sulfur compounds (VSC's), primarily hydrogen sulfide (H2S ) and methyl mercaptan (CH3SH), in the breath. Gas chromatography, an accur ate means of measuring breath VSC, vias employed to evaluate the breath lev els of VSC in 11 men after brushing with baking soda-containing dentifrices with or without the addition of Zn++. Dentifrices with either Zn++ or a co ncentration of baking soda 20% or greater significantly reduced VSC levels. The addition of Zn++ to baking soda dentifrices enhanced the anti-odor eff ects. In the first organoleptic study, dentifrices containing 20% baking so da and 30% baking soda demonstrated significantly greater ability to reduce breath odor than a standard sodium fluoride/silica dentifrice. The subject s' baseline mouth odor evaluations, initially rated as strong, declined aft er brushing with the baking soda toothpastes to a barely detectable level a t one hour, then rising to a faint level at two hours and moderate levels a t three hours. In the second organoleptic study, a dentifrice containing 65 % baking soda demonstrated significantly greater ability to reduce breath o dor than a standard sodium fluoride/silica tartar control dentifrice, but d id not differ significantly from a standard dentifrice containing 0.76% sod ium monofluorophosphate in a dicalcium phosphate dihydrate base. The result s of these studies indicate that dentifrices containing 20% or more baking soda can confer a significant odor-reducing benefit for time periods up to three hours.