Challenges in defining an efficient cleansing protocol against mono- and multi-species biofilms on a cobalt-chromium alloy surface.

BACKGROUND

Effective cleaning protocols are crucial for controlling biofilm formation on oral prostheses and preserving the oral health of patients relying on removable partial dentures (RPDs).

OBJECTIVES

The present study aimed to investigate the antibiofilm efficacy of 4 cleansing protocols on a cobalt-chromium (Co-Cr) alloy surface, which is commonly used as the base-metal framework material in dental prosthodontics.

MATERIAL AND METHODS

Cobalt-chromium specimens were contaminated with isolated strains of Candida albicans, Candida glabrata, Staphylococcus aureus, and Streptococcus mutans to form monospecies biofilms. For a multi-species biofilm, all strains were grown simultaneously on the surfaces of the specimens. After biofilm maturation, the specimens were immersed in different solutions: Ricinus communis 2%; R. communis 10%; Cepacol™; NitrAdine™; and distilled water (control). After applying the hygiene protocols, the viability of the microorganisms and the amount of residual biofilm were assessed..

RESULTS

Immersion in R. communis-based solutions did not significantly alter the viability of the microorganisms. Cepacol reduced the viability of C. albicans, C. glabrata and S. aureus in the mono-species biofilms, as well as C. glabrata in the multi-species biofilm. NitrAdine demonstrated effectiveness in reducing the viability of C. glabrata and S. mutans in both the monoand multi-species biofilms. However, its efficacy against S. aureus was only observed in the mono-species pattern. NitrAdine also reduced the area covered by the living biofilm.

CONCLUSIONS

The studied cleansing protocols exhibited reduced antimicrobial efficacy on the multispecies biofilm as compared to the mono-species model. NitrAdine showed potential as a complementary agent for controlling biofilm formation on removable partial dentures.