Abstract
BACKGROUND: Dentine hypersensitivity (DH) can occur after gum recession or enamel loss and may impact quality of life. Treatments include toothpastes that decrease DH by occluding dentine tubules. One effective occluding ingredient used in toothpastes is stannous fluoride (SnF(2)), but this can be unstable in aqueous formulation. These three studies aimed to characterise the short-term effects of an experimental, anhydrous SnF(2) dentifrice on DH. METHODS: Three examiner-blind, parallel-group studies evaluated DH in participants with the condition after a single brushing and after 3d brushing with an experimental anhydrous 0.454% SnF(2)/polyphosphate toothpaste (Test) or a toothpaste containing 0.76% sodium monofluorophosphate (Control). Test treatment participants brushed two pre-identified sensitive teeth first, then their remaining dentition for ≥1 min ('focused brushing'). Control treatment participants brushed their whole dentition for ≥1 min. DH was measured after single brushing and after 3d twice-daily use, via evaporative (air) (Schiff Sensitivity Scale) and tactile (Yeaple probe) stimuli and analysed using an ANCOVA model. RESULTS: In all studies, after 3d treatment, the Test toothpaste/brushing regimen significantly reduced DH compared to the Control regimen by both evaporative and tactile stimuli assessment (p < 0.0001 for all). The Test regimen also significantly reduced DH from baseline at both time-points by both measures in all studies (p < 0.0001 for all). Mean Schiff sensitivity score differences (95% confidence intervals) between Test and Control regimens after 3d were: Study 1: - 0.45 (- 0.577, - 0.319); Study 2: - 0.40 (- 0.505, - 0.300); Study 3: - 1.31 (- 1.500, - 1.128). Mean tactile score differences were: Study 1: 11.30 (7.927, 14.662); Study 2: 3.57 (2.531, 4.614); Study 3: 24.54 (20.349, 28.736). After single use, in Studies 2 and 3, the Test toothpaste/brushing regimen significantly reduced DH versus Control by both measures (p < 0.001 for all); in Study 1, treatment differences were not significant. Toothpastes were generally well-tolerated. CONCLUSIONS: Taken together, these studies indicated focused brushing with an experimental anhydrous 0.454% SnF(2)/polyphosphate toothpaste reduces DH compared to brushing with a conventional toothpaste after single use, with greater reduction after 3d. TRIAL REGISTRATION: Registrations at ClinicalTrials.gov : Study 1: NCT02832375 (registered 26.July.2016); Study 2: NCT02731833 (registered 26.April.2016); Study 3: NCT02923895 (registered 5.October.2016).