Clinical evaluation of the efficacy of an in-office desensitizing paste containing 8% arginine and calcium carbonate in providing instant and lasting relief of dentin hypersensitivity.

PURPOSE: To determine the efficacy of an in-office desensitizing paste containing 8% arginine and calcium carbonate relative to that of a commercially-available pumice prophylaxis paste in reducing dentin hypersensitivity instantly after a single application following a dental scaling procedure and to establish the duration of sensitivity relief over a period of 4 weeks and 12 weeks. METHODS: This was a single-center, parallel group, double-blind, stratified clinical study conducted in San Francisco, California, USA. Qualifying adult male and female subjects who presented two hypersensitive teeth with a tactile hypersensitivity score (Yeaple Probe) between 10-50 grams of force and an air blast hypersensitivity score of 2 or 3 (Schiff Cold Air Sensitivity Scale) were stratified according to their baseline hypersensitivity scores and randomly assigned within strata to one of two treatment groups: (1) A Test Paste, a desensitizing paste containing 8% arginine and calcium carbonate (Colgate-Palmolive Co); and (2) A Control Paste, Nupro pumice prophylaxis paste (Dentsply Professional). Subjects received a professionally-administered scaling procedure, after which they were re-examined for tactile and air blast dentin hypersensitivity (Post-Scaling Examinations). The assigned pastes were then applied as the final step to the professional dental cleaning procedure. Tactile and air blast dentin hypersensitivity examinations were again performed immediately after paste application. Subjects were provided with a commercially-available non-desensitizing dentifrice containing 0.243% sodium fluoride (Crest Cavity Protection, Procter & Gamble Co.) and an adult soft-bristled toothbrush and were instructed to brush their teeth for 1 minute, twice daily at home using only the toothbrush and dentifrice provided, for the next 12 weeks. Subjects returned to the testing facility 4 and 12 weeks after the single application of Test or Control paste, having refrained from all oral hygiene procedures and chewing gum for 8 hours and from eating and drinking for 4 hours, prior to each follow-up visit. Assessments of tactile and air blast hypersensitivity, and examinations of oral soft and hard tissue were repeated at these 4- and 12-week examinations. RESULTS: 68 subjects completed the 12-week study. No statistically significant differences from baseline scores were indicated at the Post-Scaling Examinations for either the Test Paste or Control Paste groups. Immediately following product application and 4 weeks after product application, subjects assigned to the Test Paste group exhibited statistically significant improvements from baseline with respect to baseline-adjusted mean air blast (44.1% and 45.9% respectively) and mean tactile hypersensitivity scores (156.2% and 170.3% respectively). At the same time points, subjects assigned to the Control Paste group exhibited statistically significant improvements from baseline with respect to baseline-adjusted mean air blast (15.1% and 8.9% respectively) and mean tactile hypersensitivity scores (43.1% and 8.3% respectively). Immediately following application of the assigned paste and 4 weeks later, the Test Paste group demonstrated statistically significant reductions in dentin hypersensitivity with respect to baseline-adjusted mean air blast (34.1% and 40.6% respectively) and mean tactile hypersensitivity scores (79.0% and 149.6% respectively), compared to the Control Paste group. No statistically significant differences were exhibited between paste groups at the Post-Scaling and 12-week examinations with respect to mean tactile and baseline-adjusted mean air blast hypersensitivity scores.