The oral cavity supports one of the most concentrated and varied microbial populations of any area of the body. It is also unique in that it provides many diverse types of habitats for the growth of microorganisms. It supports a remarkably heterogeneous, yet generally balanced, group of microbes that differs at different stages of life. In utero the fetus is germ- free but within a few months a recognizable resident microflora can be detected in all mouths. An understanding of the uniqueness of oral flora will help us recognize the pathways of disease progress in children as certain pathologic conditions such as early childhood caries are seen especially in children
