Background: A stable copper tetraamine fluoride (CTF) with low cytotoxicity has been developed for dental use.
Objective: To investigate the antimicrobial effects of CTF against common microbes associated with dental caries and periodontal disease.
Method: The minimum inhibitory concentrations (MIC) and minimum bactericidal/fungicidal concentrations (MBC/MFC) were used to evaluate the antimicrobial effects of CTF against eight common bacteria and one fungus associated with dental caries and periodontal disease. These nine microbes included cariogenic pathogens (Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilus, Lacticaseibacillus casei, Actinomyces naeslundii and Candida albicans), pulpitis-related bacteria (Enterococcus faecalis) and periodontal disease-related bacteria (Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans). Transmission electron microscopy (TEM) was employed to examine the morphological changes of microbes with and without CTF treatment.
Results: The MIC of CTF against nine microbes ranged from 80 ppm (Lacticaseibacillus casei) to 640 ppm (Candida albicans and Enterococcus faecalis). The MBC/MFC ranged from 320 ppm (Lacticaseibacillus casei) to 2560 ppm (Candida albicans). TEM revealed abnormal curvature of cell membranes, disrupted cell membranes, cytoplasmic clear zone, and cytoplasmic content leakage of the microbes treated with CTF.
Conclusion: CTF has antimicrobial effects against common oral pathogens and presents a promising antimicrobial agent to aid management of dental caries and periodontal disease.
Keywords: Caries; antibacterial; antimicrobial; copper; fluoride.