Inhibition of plaque formation in humans by octenidine mouthrinse

Octenidine, a new bispyridine antimicrobial compound, has significant antiplaque activity in animals. The present study was designed to assess the effectiveness of this agent in inhibiting plaque formation in humans. Sixty males (age 22–36 years) were randomly assigned 4 formulations which included 1) 0.1% octenidine in vehicle, 2) 0.1% octenidine in aqueous solution, 3) 0.05% octenidine in vehicle, and 4) vehicle only. After establishment of minimal levels of plaque and gingivitis, each subject rinsed twice daily under supervision with his assigned test agent. Over the next seven days, the subjects were not permitted any other means of tooth cleaning. Plaque accumulation was measured daily and gingival fluid and stain levels determined on days 0 and 7. Analysis of the data showed that both formulations of 0.1% octenidine almost completely inhibited plaque formation over the 7 day period. The vehicle had no effect on the agent's activity. The 0.05% concentration allowed some plaque accumulation, but all octenidine groups had significantly less plaque than the control group. Gingival fluid flow was significantly lower in all octenidine groups than in the control group. Tooth stain increased in all groups using the agent but remained unchanged in the group using the vehicle alone. Results of this short term clinical trial suggest that octenidine may be a useful topical antiplaque agent.