Background: Stannous fluoride has long been an effective antibacterial, anticaries, antisensitivity, and antigingivitis addition to toothpaste formulas. However, in the past its chemical properties in aqueous solution have made it difficult to stabilize with desirable results. The recent development of a novel formulation of 0.454% stannous fluoride stabilized with nitrate and phosphates (SNaP) has resulted in prolonged therapeutic effect without compromising product experience and esthetics.
Methods: Dentifrice antibacterial performance in vitro was determined through bacterial bioenergetics measured via rate of oxygen consumption and extracellular acidification in real-time comparing the SNaP toothpaste, a stannous fluoride positive control toothpaste, a non-antibacterial negative control toothpaste, and no treatment. Also, a single- center, randomized, controlled, double-blinded, clinical investigation of 98 subjects was performed to analyze dentifrice antibacterial performance in vivo following twice daily treatment with SNaP toothpaste (n = 48) and non-antibacterial control toothpaste (n = 50). Oral microenvironments, including plaque, tongue, cheek, gum, and saliva, of study participants 12 hours post-brushing were analyzed for bacterial load at baseline, 2 weeks, and 4 weeks.
Results: In vitro treatment of biofilms with SNaP toothpaste resulted in significant suppression of bacterial respiration and glycolysis compared to a positive control, negative control, and no treatment. In the clinical trial, treatment with SNaP toothpaste showed significantly lower bacterial load in all oral microenvironments 12 hours post-brushing after 2 weeks (all: P less than .01) and 4 weeks (all: P less than .05) compared to non-antibacterial negative control toothpaste. Compared to baseline, SNaP toothpaste significantly reduced bacteria from tongue (P = .007) and saliva (P less than .001) at week 2, and from all microenvironments by week 4 (all: P ≤ .001).
Conclusions: SNaP toothpaste provided significantly greater and more sustained antibacterial effects than other tested toothpastes. Stannous fluoride, when stabilized in the SNaP formulation, effectively inhibited bacterial respiration and glycolysis in saliva-derived in vitro biofilms. The specific stabilization strategy used in SNaP toothpaste is critical for the antibacterial performance of stannous fluoride, as this formulation was more effective at reducing bacterial metabolic activity than a toothpaste containing the same amount of stannous fluoride stabilized with gluconate. The clinical study supports the in vitro findings by showing that the regular use of SNaP toothpaste leads to a significant and prolonged reduction in viable bacterial counts of five oral microenvironments.
Practical implications: The highly stabilized stannous ion in SNaP toothpaste confers potent, sustained antibacterial activity that can contribute to improved oral hygiene and potentially reduce the risk of tooth decay, early gum disease, calculus, and halitosis, which have been linked to oral bacteria.