A Randomized Clinical Study Investigating the Stain-Removal Potential of Two Experimental Dentifrices

To evaluate the ability of two experimental desensitizing dentifrices, both containing a chemical cleaning agent, one with ultra-low abrasivity and one with low abrasivity, a standard fluoride dentifrice, and a daily-use whitening dentifrice to remove extrinsic tooth stain.

This was a single-center, examiner-blind, randomized, controlled, four-treatment, parallel-group study in healthy adults. Extrinsic stain was evaluated using the Macpherson modification of the Lobene Stain Index (MLSI). At baseline, eligible subjects with a total MLSI (area x intensity [A x I]) score of 15 for the facial surfaces of the 12 anterior teeth were stratified (based on total MLSI [A x I] score [< 45 = low; ≥ 45 = high] and smoking status) and randomized to treatment with one of four dentifrices: an experimental ultra-low abrasivity desensitizing dentifrice (relative dentin abrasion [RDA] -12); an experimental low abrasivity desensitizing dentifrice (RDA -40); a standard fluoride dentifrice with moderate abrasivity (RDA -80); and a whitening dentifrice with higher abrasivity (RDA -142). Both desensitizing dentifrices contained 5% potassium nitrate and 5% sodium tripolyphosphate (a chemical cleaning agent). Treatment effects were evaluated after four and eight weeks of twice-daily brushing.

In total, 142 subjects were randomized and 133 subjects completed the study. All study dentifrices demonstrated statistically significant reductions in extrinsic tooth stain from baseline after four and eight weeks of twice-daily use (p < 0.01). There were no statistically significant between-treatment differences for the primary variable (mean MLSI [A x I] score across all assessed sites) at four or eight weeks, and no notable trends were observed.

All study dentifrices reduced extrinsic tooth stain. The experimental ultra-low and low abrasivity desensitizing dentifrices containing 5% sodium tripolyphosphate performed similarly to both a moderate abrasivity standard fluoride dentifrice and a higher abrasivity whitening dentifrice.