Anticalculus effect of a dentifrice containing 0.5% zinc citrate trihydrate

A doubleblind 3-month anticalculus clinical study was conducted to determine the magnitude of the antitartar effect to be derived from use of a 0.5% zinc citrate dentifrice. From a population of 1600 subjects exhibiting calculus, 1210 subjects (age 18 and over) were selected and received a dental prophylaxis. The subjects were initially stratified on the basis of calculus score, age, and sex, then allocated randomly to a 3-month usage period of one of two treatment groups. These were a dentifrice containing 0.5% zinc citrate or a control dentifrice without zinc citrate. Calculus was assessed using the Volpe-Manhold Index. Oral soft tissue status was assessed throughout the course of the study. At the conclusion of the study 964 subjects had completed the trial: 486 using the zinc citrate dentifrice and 478 using the control. The results showed that the mean calculus scores in the group using the dentifrice containing zinc citrate were 13.7% lower than those of the group using the control dentifrice. This finding was statistically significant (P less than 0.05). No adverse effects related to the use of either dentifrice were observed.