Abstract:

Objective To compare the intraradicular bacterial community structures in under-filling teeth with or withoutperiapical infection.Methods The intraradicularbiofilm samples were collected from under-filling teeth with periapicalinfection (apical periodontitis group, 3 teeth) and underfilling teeth withoutperiapical infection (non-apical periodontitis group, 2 teeth). The V3, V6 hypervariable regions of bacterial 16S rRNA genes were amplified, and the high-throughput sequencingwasperformed. Thecomposition and structure characteristic of intraradicular microbiota were revealed by bioinformatics analysis.Results The microbiotain apical periodontitis group comprised of Firmicutes, Proteobacteria, Actinobacteriad and others, total 22 phyla. While the microbiotain non-apical periodontitis group comprised of Firmicutes, Proteobacteria, Actinobacteria and others, total 8 phyla. The complexity of the microbiotain apical periodontitis groupwas significantly higher than without apical periodontitis group, but both groups comprised thesimilar most representivephyla.Conclusion The diversity of intraradicular bacterial community in underfillingteeth with apical periodontitis was higher than those in non-apical periodontitis.

Key words: Periapical periodontitis, Metagenomic analysis, Biofilm, Microbiota, Diversity

摘要：

目的 采用宏基因分析技术比较根管治疗欠填伴或不伴明显根尖周病变患牙根管内微生物群落的构成差异。方法 临床采集根管治疗欠填5年以上后伴根尖周病变患牙（根尖周病变组,3颗）和无明显根尖周病变患牙（无根尖周病变组,2颗）根管内微生物群落样本。提取样本中细菌的总DNA,PCR扩增其对应于16S rRNA片段上的V3、V6高变区基因片段以构建宏基因组文库。经高通量测序后进行种系发育分析和主成分分析。结果 伴根尖周病变组微生物群落包含厚壁菌门、变形菌门、放线菌门等22个菌门。无明显根尖周病变组微生物群落包含厚壁菌门、变形菌门、放线菌门等8个菌门,菌门类别及占比均明显少于伴根尖周病变组,但优势菌门组成相似。结论 根管治疗后伴根尖周病变患牙的根管内微生物群落构成复杂,多样性高,与根充欠填但无明显根尖周病变患牙在根管内微生物群落构成上差别明显。

关键词: 根尖周病变, 宏基因分析, 生物膜, 微生物群落, 多样性