Differences In The Plaque Microbiome Of Toddler At Various Stages

This study investigates the successional characteristics of the dental plaque microbiome during early childhood by analyzing the composition and functional profiles of microbial communities in children of different ages. The study enrolled 54 caries-free or treated caries children aged 18–24 months (lower-month-old group) and 56 children aged 30–36 months (higher- month-old group). Dental plaque samples were collected from the labial surfaces of the maxillary deciduous incisors and subjected to third-generation full-length 16S rRNA amplicon sequencing. Comparative analyses of microbial composition and functional differences were conducted between the two groups. Alpha diversity indices (Chao1, ACE, and Shannon) were significantly higher in the higher-month-old group. PCoA analysis based on binary Jaccard distance revealed greater beta diversity in the lower-month-old group. LEfSe analysis identified 119 significantly differentiated taxonomic units, with a higher proportion enriched in the higher-month-old group. Functional analysis demonstrated significantly stronger microbial functional development in the higher-month-old group. Common oral microorganisms and caries-associated taxa begin colonizing tooth surfaces during early childhood. The diversity and functional capacity of the dental plaque microbiome undergo dynamic succession as children age. Oral hygiene practices during early childhood are essential, and modulation of the oral microbiome at this stage may be critical for preventing future dental diseases.