The plaque inhibitory effect of a CPC mouthrinse in a 3-day plaque accumulation model -A cross-over study-

Maintaining an adequate low level of plaque through daily tooth brushing is
often not feasible. Chemotherapeutic agents as an adjunct to mechanical plaque
control would be valuable. Cetylpyridinium chloride (CPC) has proven to be an
effective inhibitor of plaque accumulation.

The present study aims at testing whether a CPC-mouthrinse has a potential to
inhibit *de novo* plaque formation as compared to a placebo and hexetidine.

This study is designed as a double examiner-blind, 3-group cross-over, 3-day
plaque accumulation experiment. All participants will receive a professional
oral prophylaxis performed by an experienced dental hygienist. Subjects will
then receive a unique trial number and will be randomly assigned to one of the
3 groups according to a Latin square design. Each subject will receive a
written and verbal instruction about how to use the products. At this moment
subjects will rinse for the first time with their allocated product. All
subjects are instructed to use their allocated products 3 times a day. After 3
days, subjects return to the clinic for the clinical assessments. After
disclosing, plaque accumulation and gingivitis is scored. Subsequently all
subjects receive a questionnaire to evaluate their attitude towards the used
products using Visual Analogue Scales (VAS-scores). After the experimental
period, habitual oral hygiene procedures may be resumed.The above mentioned
procedure will be repeated twice in order to have all subjects run the protocol
with all three products. A wash-out period of 10 days is incorporated to
minimize carry-over effects.

During 3 days subjects have to rinse 3 a day with CPC-mouthrinse, Hexitine
mouthrinse or a placebo mouthrinse. The above mentioned procedure will be
repeated twice in order to have all subjects run the protocol with all three
products.

Risk for subjects: None