An In Vitro Diacetylcurcumin Study for Periodontitis: A New Approach to Controlling Subgingival Biofilms

Background: Periodontal disease (PD) is a chronic inflammatory condition associated with dysbiotic biofilm, leading to the destruction of bone and periodontal ligament. Scaling and root planing (SRP) is the gold-standard treatment for PD, but some patients may not respond adequately, necessitating adjunctive therapies. This study investigated the antimicrobial activity of diacetylcurcumin (DAC), a modified curcumin, against multispecies subgingival biofilm associated with periodontitis. Methods: The biofilm, containing 40 bacterial species, was cultured for seven days in the Calgary apparatus. Treatments with DAC (200 μg/mL), 0.12% chlorhexidine (CHX), and a vehicle (control) were applied twice daily for 1 min, starting on the third day. On the seventh day, biofilms were analyzed for metabolic activity (MA) and bacterial counts via DNA-DNA hybridization. DAC toxicity was tested on Galleria mellonella larvae. Results: DAC reduced biofilm metabolic activity by 51%, while CHX achieved 88% reduction compared to the vehicle (p < 0.05). DAC also significantly decreased counts of key periodontal pathogens, including P. gingivalis, T. forsythia, P. intermedia, and A. actinomycetemcomitans (p < 0.05). At the tested concentration, DAC showed no toxicity in larvae. Conclusions: These findings suggest that DAC effectively reduces biofilm activity and periodontal pathogen counts, presenting a promising adjunctive therapy for PD.