Randomized controlled trial to study plaque inhibition in calcium sodium phosphosilicate dentifrices

To evaluate the effect of three calcium sodium phosphosilicate (CSPS)/sodium monofluorophosphate containing dentifrices, compared to positive and negative controls on plaque re-growth in a non-brushing model, after 4 days of twice daily use, as determined by plaque area and Turesky plaque index (TPI).

This was an exploratory, single-centre, examiner-blind, randomised, controlled, five treatment period, crossover, plaque re-growth study, with supervised use of study products. Twenty-three healthy adult volunteers were randomized to receive experimental 5% CSPS dentifrice; two marketed 5% CSPS dentifrices; active comparator mouthrinse and negative control dentifrice. At the start of each treatment period, zero plaque was established by dental prophylaxis and study products were dispensed as either dentifrice slurries or mouthrinse, twice daily for the next 4 days. No other forms of oral hygiene were permitted. After 96h, supra-gingival plaque was determined by plaque area (direct entry, planimetric method) and TPI. Changes from zero plaque were analysed.

For both measures, plaque re-growth at 96h was significantly lower following treatment with active comparator mouthrinse and significantly higher following treatment with the experimental 5% CSPS dentifrice, compared to all other treatments. There were no statistically significant differences between the three other treatments, except between the marketed 5% CSPS dentifrices, for overall plaque area.

The comparator mouthwash was significantly more effective at preventing plaque accumulation than the dentifrice slurries. The three marketed dentifrices contained sodium lauryl sulphate and were more effective at reducing plaque re-growth than the experimental dentifrice formulated with a tegobetaine/adinol surfactant system.

The CSPS containing dentifrices tested in this study showed no significant chemical-therapeutic anti-plaque benefits compared to a negative control dentifrice. However, sodium lauryl sulphate-containing dentifrices controlled plaque more effectively than a tegobetaine/adinol-containing CSPS dentifrice suggesting that the impact of surfactant selection on anti-plaque activity of formulations warrants further investigation.