Objective: The objective of this double-blind, randomized, parallel-design clinical study was to compare the efficacy in reducing dentin hypersensitivity of a novel toothpaste containing 8.0% arginine, calcium carbonate, and 1450 ppm fluoride to a benchmark desensitizing toothpaste containing 2% potassium ion and 1450 ppm fluoride, and to a control toothpaste containing 1450 ppm fluoride, instantly after a single direct topical self-application using a fingertip, and after subsequent brushing twice daily for three days.
Methods: Qualifying subjects from the Mississauga, Canada area who presented two hypersensitive teeth with a tactile hypersensitivity score (Yeaple Probe) between 10 and 50 grams of force, and an air blast hypersensitivity score of 2 or 3 (Schiff Sensitivity Scale) participated in this study. The first phase of the study consisted of a single topical application of the assigned product directly onto the hypersensitive surface of each of the two baseline-designated hypersensitive teeth. Study subjects applied a pea-size amount of their assigned toothpaste onto the hypersensitive surface of each tooth, and massaged each surface for one minute. The second phase of the study consisted of twice-daily at-home brushing with the assigned toothpaste for three days. Dentin hypersensitivity assessments, as well as examinations of oral hard and soft tissues, were conducted at baseline, immediately after direct topical application, and after three days of product use.
Results: One-hundred and twenty subjects complied with the protocol and completed the study. Relative to the desensitizing toothpaste and the control toothpaste groups, the 8.0% arginine toothpaste group exhibited statistically significant (p < 0.05) reductions in dentin hypersensitivity on both tactile and air blast measures immediately after completion of the first phase of the study. Reductions in sensitivity for the 8.0% arginine toothpaste, compared to the benchmark desensitizing toothpaste and the control toothpaste, were 130.7% and 139.5% (tactile), and 43.8.0% and 49.6% (air blast), respectively. Relative to the benchmark desensitizing toothpaste and control toothpaste groups, the 8.0% arginine group also exhibited statistically significantly (p < 0.05) reductions in sensitivity after completion of the second phase of the study, of 104.9% and 136.1% (tactile), and 44.5% and 53.2% (air blast), respectively. There was no loss of the instant relief effects in the 8.0% arginine group after the brushing period.
Conclusion: A single fingertip topical self-application of the 8.0% arginine-calcium carbonate toothpaste directly onto the hypersensitive surface of teeth provides significant immediate improvements in dentin hypersensitivity relative to an identical application of the control toothpaste and to the benchmark potassium-based desensitizing toothpaste. Significant improvements in dentin hypersensitivity were also demonstrated after three days of brushing with the 8.0% arginine-calcium carbonate toothpaste, subsequent to the single topical self-application of the product, relative to an identical application of the control toothpaste and to the benchmark potassium-based desensitizing toothpaste. The improvement demonstrated by the 8.0% arginine toothpaste after direct application was maintained after three days of twice-daily brushing.