Cariogenic bacteria in dental plaque biofilm

Cariogenic bacteria in dental plaque biofilm refer to a diverse community of acid-producing microorganisms, most notably Streptococcus mutans and various Lactobacillus species, that adhere to tooth surfaces (NIH, 2020). These bacteria organize into a complex extracellular matrix known as a biofilm, which provides a protective environment against host defenses and antimicrobial agents (StatPearls, 2023). The primary pathological mechanism involves the fermentation of dietary sugars into organic acids, which lowers the local pH below the critical threshold of approximately 5.5. This acidic environment leads to the demineralization of dental enamel and the subsequent formation of dental caries (PubMed, 2021). Therapeutic interventions target this biofilm through mechanical removal, the use of antimicrobial agents like chlorhexidine to disrupt cell membranes, and fluoride to inhibit bacterial metabolism and promote remineralization (Journal of Dental Research, 2019). Understanding the dynamics of this microbial community is essential for developing targeted therapies that can shift the oral microbiome from a dysbiotic, disease-associated state back to a symbiotic, healthy state. While considered a therapeutic target, it is classified as incorrect in a strictly molecular context because it represents a multi-species biological community rather than a single protein or receptor.

Other names

Dental plaqueCariogenic microfloraAcidogenic oral bacteriaOral biofilmDental biofilm

Drugs targeting cariogenic bacteria employ several strategies: fluoride ions inhibit the enzyme enolase in the glycolytic pathway, reducing acid production, and also integrate into the tooth crystal lattice to form fluorapatite (StatPearls, 2023). Antiseptics like chlorhexidine and cetylpyridinium chloride carry a positive charge that binds to negatively charged bacterial cell walls, causing membrane disruption and cytoplasmic leakage (PubChem). Xylitol serves as a competitive inhibitor that Streptococcus mutans cannot ferment, leading to a futile cycle of energy expenditure and reduced bacterial growth (PubMed, 2017). Silver diamine fluoride acts by denaturing bacterial proteins and DNA while simultaneously promoting the hardening of the tooth structure through fluoride-mediated remineralization.