Plaque Microbial Communities Associated with Severe Early Childhood Caries

Background: Early Childhood Caries (ECC), especially Severe Early Childhood Caries(S-ECC), may seriously affect children’s physical and mental health. According to the previous survey, 81.3% caries are concentrated in 24.8% of children, which indicates a population of high risk and great challenges to pedodentists.Oral bacteria, especially the plaque community is one of the conditions for theoccurrence of dental caries. High throughput sequencing techniques now enable us to explore the microbial diversity at the level of DNA, and to further understand their roles. we compared the plaque microbial profiles of healthy young children and those with caries by using high-throughput sequencing, trying to reveal the potential pathogenic bacteria and pathogenesis.

Methods: Plaque samples were obtained from children(3-6 year-old) with S-ECC (group S. n=36), ECC(group E. n=28) and caries-free(CF) children (group C.n=30). Total metagenomic DNA was extracted and DNA amplicons of the V3 and V4 hypervariable region of the 16S rRNA gene were generated and subjected to hiseq sequencing. The characteristics of oral microbial communities from the three groups were compared based on three microbial diversity and taxonomy assignment.

Results:First. the microbial community structure was significantly different for the three groups. Lactobacillus(p<0.01), Megasphaera, Catonella, Parascardovia(p<0.01)、Bifidobacterium, Veillonella, Prevotella7、Atopobium、Scardovia were rich in group S. Eikenella, were rich in group C. Neisseria, Alloprevotella, Peptostreptococcus, Catonella were rich in group E.

Second, some microbiota especially Megasphaera、Scardovia、Lactobacillus、Bifidobacterium were positively correlated with dmfs. Eikenella was negatively correlated with dmfs.

Conclusion: Plaque microbiota and certain taxa. such as Megasphaera、Scardovia、Lactobacillus、Bifidobacterium may be useful to screen the children`s risk of developing caries.