Clinical Effects of Increasing Toothpaste Abrasivity on Tooth Hypersensitivity

Objective: To evaluate the effect of dentifrices with differing levels of abrasivity on existing cervical dentinal hypersensitivity(CDH).

Methods: An eight-week randomized, single center, stratified, double-blind, placebo controlled clinical study was conducted to determine changes in CDH using four dentifrices differing in abrasivity. A respnse from the subject was elicited using the evaporative or thermal method consisting of a one-second air blast from the air syringe of a dental unit. Subjects assessed their CDH at baseline and at four and eight weeks utilizing the standard visual analog pain scale(VAS) of 100 mm. A totol of 141 subjects completed the study. Subjects were stratified into two groups by age, 18-30, and 31-65 and randomly assigned to one of four dentifrices varying in relative dentin abrasivity(RDA) ranging from 60, 108, 150, 210. Subjects were instructed to brush for one minute twice daily in their customary manner.

Results: A mean thermal VAS score was calculated for each subject by averaging the scores of both teeth. An analysis of covariance was performed on the change from baseline scores data using the baseline scores as a covariate. After four and eight weeks of product use, there were no statistically significant difference among study groups when assessed using a self report visual analog scale for the repoonse of an air blast causing thermal stimulation of the cervical dentin.

Conclusions: Dentifrices ranging in RDA from as low as 60 to a high of 210 do not affect the response of subjects with existing cervical dentin hypersensitivity. There appears to be no relationship between RDA values and dentinal hypersensitivity.

Supported by a grant from Colgate-Palmolive