This 6-month, double-blind clinical study, also following the American Dental Association guidelines, investigated the efficacy of Colgate Optimized Stannous Fluoride (COSF) dentifrice in controlling supragingival dental plaque and gingivitis. The same dentifrice, containing 0.454% stannous fluoride, stannous chloride, polyphosphate, and citrate in a silica base was used. Adult men and women from the Atlanta, Georgia, area received an oral prophylaxis and were instructed to brush their teeth twice daily (morning and evening) for 1 minute with their assigned dentifrice, using a soft-bristled toothbrush. As in the first study, plaque and gingivitis examinations were conducted after 3 months and again after 6 months of using the dentifrices. At both the 3- and 6-month study examinations, the COSF dentifrice group exhibited statistically significant reductions in both plaque and gingivitis compared to the control dentifrice group. At the 6-month examination, the magnitude of these percent reductions exceeded 20% for all 4 parameters measured. Thus, the results of this study reflect those found in the New Jersey study, i.e., supporting the conclusion that the COSF dentifrice is efficacious for the control of supragingival plaque and gingivitis.