Dental plaque control effect of a zinc citrate dentifrice.

OBJECTIVE: This research evaluated the antiplaque efficacy of a new 2% zinc citrate fluoride dentifrice versus a non-zinc matching placebo or a commercial fluoride dentifrice, also used as the washout product in two crossover studies. METHODS: Healthy human subjects meeting inclusion criteria entered two respective randomized crossover clinical studies. Study 1 had 24 subjects, and compared the zinc dentifrice to the commercial fluoride dentifrice over a 24-hour period. Study 2 had 19 subjects, and compared the zinc dentifrice to the matching placebo over a 24-hour period. After one week of washout using the commercial fluoride dentifrice, the subjects used the test product for one week prior to the test period. Both studies employed the Modified Gingival Margin Plaque Index (MGMPI) for the assessments. RESULTS: In Study 1, the mean differences in the MGMPI score, representing post-treatment plaque regrowth along the gingival margin for the zinc prototype as compared to the commercial fluoride dentifrice, were 13.87 (+/- 8.27) and 21.23 (+/- 11.08), respectively. Study 2 demonstrated the mean differences in MGMPI scores for the zinc dentifrice and a matching placebo of 14.99 (+/- 13.32) and 24.38 (+/- 7.69), respectively. In both studies, the zinc dentifrice demonstrated a significant 35% and 39% inhibition of dental plaque formation compared to those of their respective control dentifrices. CONCLUSION: Two clinical studies demonstrated plaque control efficacy for a new zinc citrate-containing dentifrice, suggesting a new antiplaque and possible multi-benefit dentifrice for oral hygiene.