plaque
Thirty-six children aged 3 to 5 years were selected, including 12 children without caries, 12 children with AC and 12 children with RC. Seventy-two noninduced saliva and dental plaque samples from primary dentition were collected. Using the MiSeq platform, 16S rRNA gene sequencing of the V3-V4 region was used to determine the bacterial spectrum. Operational taxonomic unit-based analysis, including alpha and beta diversity analysis, principal coordinate analysis and linear discriminant analysis effect size (LEfSe), was used to analyse the structure and composition of the microbial community.