The role of oral biofilms and periodontal disease
The oral cavity is home to a highly diverse microbial ecosystem, where microorganisms thrive due to unique environmental conditions that support adhesion and growth. The process begins with the adsorption of salivary pellicle proteins onto oral surfaces, creating a substrate for microbial colonization. Over time, these microorganisms form biofilms—highly organized communities embedded in an extracellular matrix. Biofilms offer significant survival advantages to bacteria, including protection against antimicrobial agents and host immune defenses, along with enhanced co-aggregation and interaction. Understanding this process highlights how biofilms provide a robust foundation for microbial resilience and pathogenic potential.
Polymicrobial biofilms play a central role in the onset of several oral diseases, such as dental caries, periodontal diseases, implant-related infections, and oropharyngeal candidiasis. The pathogenic nature of these biofilms emerges when endogenous oral bacteria, exposed to dietary sugars, disrupt the balance between tooth minerals and ions in the biofilm fluid. The bacterial metabolism of sugars produces acids that lower the pH, leading to demineralization of tooth structures and visible cavities. This underscores the critical role biofilms play in facilitating disease progression, driven by environmental imbalances and dietary influences.
In periodontal diseases, bacteria within biofilms are the primary etiological agents, forming complex structures on teeth, gingival tissues, and implanted materials. Site-specific factors such as nutrition, spatial limitations, and metabolic activity shape these biofilms, allowing for highly specialized microbial communities. These structures not only resist the host's immune response but also provoke persistent inflammation, driving tissue damage. This relationship between biofilms and periodontal diseases demonstrates how these microbial communities are intricately linked to chronic oral health conditions.
While the mechanisms underlying biofilm-related diseases are increasingly understood, research continues to explore the immune-inflammatory pathways that transition oral health to disease. The composition and structural complexity of biofilms make them formidable contributors to oral diseases, resisting both host defenses and therapeutic interventions. By investigating these interactions further, researchers aim to develop targeted strategies to mitigate biofilm-related oral diseases and maintain long-term oral health.
Bertolini, M., Costa, R. C., Barão, V. A. R., Cunha Villar, C., Retamal-Valdes, B., Feres, M., & Silva Souza, J. G. (2022). Oral Microorganisms and Biofilms: New Insights to Defeat the Main Etiologic Factor of Oral Diseases. Microorganisms, 10(12), 2413. https://doi.org/10.3390/microorganisms10122413