This review article examines the human oral microbiome, a highly diverse and ecologically complex community consisting of bacteria, archaea, viruses, and microeukaryotes. It highlights the intricate, structured biogeography of these microbial communities within the various microenvironments of the oral cavity, which shapes local metabolic activity. The article explores the crucial interface between the oral microbiota and the host's immune system, emphasizing its significant role in maintaining both oral and systemic health. Recent advances are discussed, including new insights into species-level biogeography, the ecological function of candidate phyla radiation bacteria, and the impact of non-bacterial microbes. Furthermore, the review summarizes the established connections between the oral microbiota and the pathology of various oral and systemic diseases, aiming to provide a holistic understanding that can inform future preventive and therapeutic strategies.
The Oral Microbiome: Key Concepts in Diversity, Structure, and Health
Diverse Composition: The oral microbiome is a complex ecosystem comprising a wide variety of microorganisms, including bacteria, microeukaryotes (like fungi), archaea, and viruses.
Complex Biogeography: Microbes in the mouth are not randomly distributed but form highly structured communities. Their specific location (e.g., on the tooth surface, tongue, or gums) is determined by the unique microenvironments present, a concept known as biogeography.
Impact on Health: The oral microbiota is fundamental to human health, influencing not only the condition of the oral cavity (e.g., preventing or causing diseases like cavities and periodontitis) but also affecting overall systemic health.
Host-Microbe Interaction: There is a constant and important interaction between the oral microbial communities and the human immune system.
Emerging Research: The field is advancing with new discoveries about the specific roles of less-understood microbes, such as candidate phyla radiation (CPR) bacteria, and non-bacterial members of the microbiome.
Link to Systemic Disease: The review highlights the growing body of evidence connecting the oral microbiota to the pathology of systemic diseases beyond the mouth.
Future Applications: A comprehensive understanding of the oral microbiome is essential for developing novel preventive and therapeutic strategies to improve both oral and systemic health.