ABSTRACT
This chapter discusses the composition and diversity of human oral microbiome. The term microbiome was proposed by Nobel laureate Joshua Lederberg to signify the ecological community of commensal, symbiotic and pathogenic microorganisms that literally share our body space. The oral microbiome is one of the most diverse and complex microbiomes in the human body. The two types of microbiome that exist across body habitats are variable microbiome and core microbiome. The oral microbiota continuously slough into the saliva, rendering salivary microbiome as a blueprint of the oral microbiome. Viruses are integral members of the human oral microbiome. In the oral microbiome, bacteriophages constitute a significant population as compared to the eukaryotic viruses which are also members of the microbiome. As many of the oral bacteriophages have been identified to have lysogenic lifestyles, they have the capability to alter the oral bacteriome substantially. Bacteriophages also play a role in driving bacterial diversity in dental plaque biofilms.
