Efficacy of Benzydamine and Cetylpyridinium Mouth-rinse on De-novo Plaque Formation

Objective: To evaluate the effect of a mouth-rinse formulation combining benzydamine hydrochloride and cetylpyridinium chloride (BNZ+CPC) in preventing de novo plaque formation, in comparison with cetylpyridinium chloride (CPC) and placebo mouth-rinses. Methods: This was a controlled, observer blind, cross-over study. In this model of plaque regrowth, subjects received a session of oral prophylaxis and were directed to withdraw oral hygiene measures for the next 4 days, using only the mouthrinse assigned. The outcome parameters were the Plaque Index (PlI) and Gingival Index (GI). In addition, microbiological evaluation of the subgingival microflora, by means of culture, was performed, as well as patient-based variables. Data analysis was carried out using ANOVA for Latin square design. Results: The analysis of variance showed a significant statistical difference between the BNZ+CPC association and placebo (p<0.0001). No differences between CPC and placebo were detected considering multiple comparisons between treatments. The 90% confidence interval of the differences between BNZ+CPC and CPC showed no equivalence between treatments, being the PlI lower in the BNZ+CPC group. No significant difference between groups in GI were observed. Mean anaerobic CFU demonstrated a significant increase between visits in all groups (p<0.001) and differences among groups were not significant. Subjects treated with BNZ+CPC frequently reported “tingling mouth” and “numbness mouth”. Conclusion: Within the limitations of the study model, the BNZ+CPC combination showed a statistically significant plaque inhibitory capacity, as compared with the placebo mouth-rinse, and superior as compared with CPC. No relevant clinical or microbiological adverse effects were detected. Supported by LRU grant by ACRAF.