Extrinsic Stain Removal Efficacy of Dual-Zinc-Arginine Dentifrices

Objectives: To assess the extrinsic tooth stain removal efficacy of two test toothpastes containing 0.96% zinc (zinc oxide, zinc citrate) and 1.5% arginine.
Methods: One-hundred-fifty-two adults from Santo Domingo, Dominican Republic were randomly assigned to brush twice daily using one of three 1450ppm NaF dentifrices: (Test 1) 0.96% zinc (zinc oxide, zinc citrate) and 1.5% arginine in a high cleaning silica base (Test 2) 0.96% zinc (zinc oxide, zinc citrate) and 1.5% arginine in a silica base; (3-Neg Control) non-whitening toothpaste in a silica base. Extrinsic Stain Area and Stain Intensity examinations (Lobene) were repeated after three and six weeks of product use.
Results: At the 3-week examination, subjects assigned to Test 1 and Test 2 exhibited statistically significant reductions of 28.6% and 30.0%, respectively, in Stain Area Index as compared to the Negative Control.

At the 3-week examination, subjects assigned to Test 1 and Test 2 exhibited statistically significant reductions of 31.5% and 28.5%, respectively, in Stain Intensity Index as compared to the Negative Control.

At the 6-week examination, subjects assigned to Test 1 and Test 2 exhibited statistically significant reductions of 49.0% and 40.4%, respectively, in Stain Area Index as compared to the Negative Control. .

At the 6-week examination, subjects assigned to Test 1 and Test 2 exhibited statistically significant reductions of 43.5% and 31.5%, respectively, in Stain Intensity Index as compared to the Negative Control.
Conclusions: Both dual zinc/arginine test dentifrice products demonstrated significant extrinsic tooth stain removal benefit after three and six weeks of twice daily brushing.