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Oral Biofilm Sampling for Microbiome Analysis in Healthy Children
Published on: December 31, 2017
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Microbiota associated with caries and apical periodontitis: A next-generation sequencing study
Euon Jung Tak1, Ok-Jin Park2, Jin-Sun Lee2
1Department of Life and Nanopharmaceutical Sciences and Department of Biology, Kyung Hee University, Seoul, Republic of Korea.
International Endodontic Journal
|March 12, 2025
Summary
Microbial communities in root canals with apical periodontitis differ from dental biofilms. Specific bacteria found in caries-affected dentine and root canals, like Hallela multisaccharivorax, are linked to primary apical periodontitis development.
Area of Science:
- Microbiology
- Dental Research
- Infectious Diseases
Background:
- Dental caries and apical periodontitis are common oral infections.
- Understanding the microbial etiology of these conditions is crucial for effective treatment.
- The relationship between oral biofilms and root canal microbiota in primary apical periodontitis requires further investigation.
Purpose of the Study:
- To investigate the correlation between the microbiota of caries-free enamel biofilms, caries-affected dentine biofilms, and root canals in teeth with primary apical periodontitis.
- To compare bacterial community structures across different oral sample sites using high-throughput sequencing.
Main Methods:
- Biofilm samples from caries-free enamel (Biofilm-C) and caries-affected dentine (Biofilm-E), along with root canal samples (Canal), were collected from 31 patients.
- Microbial composition was analyzed using 16S rRNA gene amplicon sequencing on an Illumina MiSeq platform.
- Statistical analyses included Kruskal-Wallis test, pairwise permutational multivariate analysis of variance, and MaAsLin2 for differential abundance analysis.
Main Results:
- A total of 16 phyla, 130 genera, and 314 species were identified.
- Distinct bacterial communities were observed between biofilm and root canal samples, with no significant alpha diversity differences.
- Several genera, including Acinetobacter, Dialister, and Parvimonas, were more abundant in root canal samples. Hallella, Lactobacillus, and Olsenella were increased in caries-affected dentine compared to caries-free enamel.
Conclusions:
- Bacterial community structures significantly differed between root canal samples and oral biofilms.
- No significant differences in biofilm communities were found based on caries status.
- Specific taxa, such as Hallela multisaccharivorax, Olsenella uli, and Lactobacillus gasseri, were abundant in both caries-affected dentine and root canals, suggesting their critical role in primary apical periodontitis pathogenesis.
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