Anticalculus efficacy of an essential oil dentifrice containing 1.3% pyrophosphate ion

One-hundred and fifty (150) healthy adult subjects, who readily form dental calculus under normal brushing conditions, completed this study to determine the efficacy of an essential oil dentifrice formulation containing 1.3% pyrophosphate ion (PPi) in inhibiting the development of supragingival calculus, compared to a commercially available control dentifrice (Crest Regular). This study was conducted in two phases: an 8-week pre-trial phase (Phase I) to identify a suitable calculus forming population, and a 12-week trial phase (Phase II) utilizing a randomized, double-blind, parallel group design. Calculus scores from Phase I were used to form balanced groups for Phase II. At the start of Phase I, subjects received a thorough dental prophylaxis and were instructed to brush twice daily for 60 seconds with the control dentifrice. At 8 weeks, subjects were scored for calculus; subjects with a Volpe-Manhold Calculus Index score > or = 7.0 qualified to enter Phase II. Qualifying subjects were stratified by calculus scores and randomly assigned to one of two treatment groups. Subjects then received a baseline oral soft tissue examination and dental prophylaxis, and began twice-daily brushing with their assigned dentifrice for 12 weeks. At 12 weeks, subjects received an oral soft tissue examination and were re-scored for calculus. The 1.3% PPi dentifrice group mean score was statistically significantly different (p = 0.03) from the control dentifrice group mean score, producing a 14.1% calculus reduction. In this study the essential oil dentifrice containing 1.3% pyrophosphate ion was effective in inhibiting the development of supragingival calculus.