A 24-h regrowth study to evaluate the plaque inhibitory properties of a proprietary liquid dentifrice

Dentifrices have typically been formulated as pastes. Recently however, a n umber of liquid products have become available. The chemical plaque inhibit ory activity of such products has so far received little attention. The aim of this study was to determine the plaque inhibitory effect of a proprieta ry liquid dentifrice by comparison to a negative control (water) and a conv entional fluoride toothpaste. The study design was a randomised single cent re, single blind 3-way crossover trial with the objective of validating cla ims of plaque inhibition for the liquid dentifrice. Volunteers were rendere d plaque free then asked to brush for one minute with one of the three test products, following which they abstained from oral hygiene for the subsequ ent 24 h. The plaque area was recorded and then measured planimetrically. T he results showed that more plaque accumulated with water and the liquid de ntifrice compared with the fluoride toothpaste. Thus, there: was a statisti cally significant difference between the fluoride toothpaste and water and between the fluoride toothpaste and the liquid dentifrice. There was no sig nificant difference between the liquid dentifrice and water. It is conclude d that in this particular model system, the liquid dentifrice provided litt le chemical plaque inhibitory action.