Antimicrobial effect of cinnamaldehyde in a peri-implant mucositis model

Evaluate the antimicrobial effect of an experimental mouthwash containing 1 % cinnamaldehyde in a polymicrobial biofilm model for peri-implant mucositis.

Polymicrobial biofilms were seeded on zirconia and on titanium (n = 6 or 8/group) surfaces from stimulated saliva collection from 2 periodontal health donors and 2 with gingivitis. Salivary pellicle was performed, by 60 min. Inoculum was seeded (1 ×10⁸ CFU/mL) in McBain medium (1 % of sucrose). Biofilms on zirconia were cultured in aerobiosis and on titanium in microaerophilic conditions for 24 h. Daily challenges with 10 % sucrose were stablished. Samples were exposed to the experimental mouthwash for 1 min, twice a day, for 72 h. Chlorhexidine digluconate at 0.12 % and saline solution (at 0.9 %) were used as controls. Biofilms were kept in culture for an additional 24 h to count viable cells, evaluate biomass and cellular metabolism.

In zirconia, evaluation of cellular metabolism did not detect a statistically significant difference between the biofilm conditions (p > 0.05). It was found that cellular metabolism was decreased from exposure to mouthwash and chlorhexidine, with a difference compared to the negative control (p < 0.05). In titanium, viable cell count in two media and the biomass were higher for biofilms from the periodontal health salivary condition (p < 0.05). There was a decrease in the biomass of biofilms exposed to the experimental mouthwash for both salivary conditions. Metabolic activity was decreased when exposed to experimental mouthwash and chlorhexidine compared to the negative control (p < 0.05).

Experimental mouthwash with 1 % cinnamaldehyde showed an antimicrobial effect similar to chlorhexidine against polymicrobial biofilms.