16S rRNA gene sequencing-based preliminary study on the differences in the microbiota between children with rampant caries and those with arrested caries

Objective: At present, there are no studies on the microbial community of children with arrested caries (AC) and rampant caries (RC).This research study the differences in microbial profiles among caries-free (CF), AC and RC patients.Methods: 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.Results: Alpha diversity analysis revealed that in certain disease conditions (AC and RC groups), there were also significant differences in microbial diversity between saliva and dental plaque. The similarity analysis results (P<0.05) revealed significant differences in the microbial community structures among the different sampling points. These results suggest significant differences in the microbial community structures of saliva and dental plaque samples from children with different disease states. LEfSe revealed that the potential bacteria associated with CF were Leptotrichia, Porphyromonas, Actinomyces, Neisseria, Rothia_dentocariosa, and Capnocytophaga. Potential bacteria associated with AC are Prevotella, Streptococcus, Streptococcus mutans, Megasphaera, Campylobacter, and Propionibacterium. Potential bacteria associated with RC include Selenomonas, Lactobacillus, Veillonella and Prevotella.Conclusion: This study highlights the significant microbial differences between children with various caries conditions, suggesting that specific bacteria are associated with CF, AC, and RC states. Understanding these microbial profiles could lead to better prevention and treatment strategies for dental caries in children.