Long-Lasting Efficacy of an Experimental 1450 ppm Fluoride/Zinc-Based Dentifrice as Measured by Calcium Buildup Using an In Situ Intra-Oral Device After 12 Hours: A Randomized Clinical Trial.

OBJECTIVE: To assess the efficacy of an experimental 1450 ppm fluoride as sodium monofluorophosphate (SMFP)/zinc-based dentifrice (Test), a clinically proven 1450 ppm fluoride as SMFP/zinc-based dentifrice (Positive Control), and a 1000 ppm fluoride as SMFP and 450 ppm fluoride as sodium fluoride (NaF) dentifrice (Negative Control) in delivering 12-hour anti-tartar benefits as measured by calcium buildup after a single product brushing.

METHODS: Fourteen (14) adult subjects completed this single-center, double-blind, randomized, cross-over clinical study conducted in Piscataway, New Jersey. An intra-oral appliance was custom-made for each subject as a surface on which the anti-calculus agents' inhibition of early calculus formation could be analyzed. After brushing with their assigned toothpaste, each subject wore their respective appliance for 12 hours overnight. When the appliance was removed, it was washed, suspended in 0.1 MHCL to release Ca2+ from deposits, and analyzed by Inductively Coupled Plasma (ICP) for deposited calcium. There was a one-week washout period between each product use. Statistical analyses were performed on the mean level of calcium (μg). Comparisons of the treatment groups with respect to 12-hour post-brushing (overnight) calcium levels were performed via a two-way analysis of variance (ANOVA), with subjects and products as factors in the ANOVA model. Post-ANOVA pair-wise comparisons of the study treatments were performed using the Tukey's test for multiple comparisons. All statistical tests of hypothesis were two-sided, and employed a level of significance of α = 0.05.

RESULTS: At the 12-hour post-brushing examination, the mean level of calcium buildup was 0.46 μg for subjects assigned to the experimental Test dentifrice, 0.41 μg for subjects assigned to the Positive Control dentifrice, and 2.47 μg for subjects assigned to the Negative Control dentifrice. After 12 hours post-brushing, subjects assigned to the experimental Test dentifrice and Positive Control dentifrice both exhibited statistically significantly (p = 0.005 and p = 0.004, respectively) lower levels of calcium buildup as compared to the subjects assigned to the Negative Control dentifrice. No statistically significant (p = 0.996) difference was observed between the experimental Test dentifrice and Positive Control dentifrice with respect to tartar control efficacy after 12 hours post-brushing. No adverse effects of the hard or soft oral tissue were observed by the clinical investigators or reported by the subjects.

CONCLUSION: Both the experimental Test dentifrice (1450 ppm fluoride as SMFP/zinc-based dentifrice) and the Positive Control dentifrice (1450 ppm fluoride as SMFP/zinc-based dentifrice) provided significantly greater 12-hour tartar control as measured by calcium buildup, as compared to the Negative Control dentifrice containing 1000 ppm fluoride as SMFP and 450 ppm fluoride as NaF.