Comparative Investigation of the Antimicrobial Effects of Cerium Complex with Black and Green Tea Extracts

Dental floss functionality can be enhanced to provide additional benefits beyond mechanical plaque removal. Novel coating techniques offer the potential for delivering antimicrobial and anti-inflammatory agents directly to interdental spaces.

The objective of this study is to develop and evaluate a dual-layer coating of polydopamine [PDA] and cerium-tea complex on dental floss for improved functionality and antimicrobial properties.

Cerium complexes with black tea [Ce-BT] and green tea [Ce-GT] extracts were synthesized using a green synthesis method. The coatings were characterized using FTIR spectroscopy, SEM-EDX analysis, and DLS. Coated floss was evaluated for weight increase, tensile strength, and coating transfer. Antimicrobial assays were conducted against Escherichia coli, Staphylococcus aureus, Candida albicans, Streptococcus mutans and Porphyromonas gingivalis.

TIR confirmed successful complex formation between Ce³⁺ ions and tea polyphenols. SEM imaging revealed amorphous structures on coated threads, while EDX analysis confirmed the presence of cerium. The dual-layer coating significantly increased floss weight [53.69% total increase] and improved its tensile strength. Simulated flossing tests demonstrated coating transfer to interdental spaces. Antimicrobial assays showed strong inhibition against tested microorganisms, with Ce-GT exhibiting superior antimicrobial properties compared to Ce-BT. In addition, Ce-BT and Ce-GT coated silk threads showed greater antimicrobial properties in inhibiting the growth of selected microbial strains when compared with a control group of 0.12% chlorhexidine coated silk threads, although there was no significant difference between the groups when tested with one-way ANOVA. The coated floss maintained appropriate mechanical properties for dental applications.

This innovative dual-layer coating approach presents a promising method for delivering antibacterial and anti-inflammatory agents directly to interdental spaces, potentially offering an effective over-the-counter solution for periodontal disease prevention and treatment. Future research should focus on optimizing the coating process, evaluating efficacy against specific oral pathogens, and conducting in vivo studies to assess clinical outcomes.