ABSTRACT
PURPOSE: To evaluate the efficacy of an experimental mouthwash containing 3% potassium nitrate (KNO3) in relieving dentin hypersensitivity when used as an adjunct to brushing with fluoride toothpaste compared with use of the same toothpaste alone. METHODS: This was one of three randomized, two-treatment, examiner-blind, parallel-design, single-site, 8-week studies in healthy subjects with self-reported and clinically diagnosed dentin hypersensitivity. Subjects were randomized to receive either fluoride toothpaste plus 3% KNO3 mouthwash or the same fluoride toothpaste alone, and instructed to use their allocated treatment twice daily for the next 8 weeks. Dentin hypersensitivity was evaluated at baseline and following 4 and 8 weeks of treatment through assessment of responses to evaporative (air) and tactile stimuli [measured by the Schiff Sensitivity Scale, a visual rating scale (VRS), and tactile threshold, respectively], and using the Dentin Hypersensitivity Experience Questionnaire (DHEQ; a validated quality-of-life instrument for dentin hypersensitivity). RESULTS: A total of 216 subjects were randomized and 214 completed the study. Both treatment groups demonstrated statistically significant reductions from baseline for each clinical measure of sensitivity (P≤ 0.01) at Weeks 4 and 8. Use of the 3% KNO3 mouthwash after brushing with fluoride toothpaste resulted in statistically significantly greater reductions in sensitivity to an evaporative (air) stimulus (mean Schiff score and mean VRS, P< 0.001; primary objective mean Schiff score at Week 8, P< 0.0001) and statistically significantly higher tactile threshold (P< 0.001) at Weeks 4 and 8 compared with toothpaste alone. The DHEQ responses reflected the clinical outcomes for several parameters, indicating a significant improvement in oral health-related quality of life after 8 weeks' use of the 3% KNO3 mouthwash. CLINICAL SIGNIFICANCE: The results of this study suggest that daily use of a 3% KNO3 mouthwash as an adjunct to brushing with fluoride toothpaste provides clinically relevant improvements in dentin hypersensitivity after 8 weeks' twice-daily use.