Microbiome differences between trauma- and caries-derived periapical lesions using next-generation sequencing.

Background: While the microbiome of caries-derived periapical lesions has been extensively characterized, the microbial profile of trauma-derived periapical lesions remains poorly understood. This study aimed to characterize the apical microbiome of trauma-derived periapical lesions and identify taxonomic differences between trauma- and caries-derived periapical lesions.

Methods: Twenty patients with periapical lesions were enrolled, comprising 10 trauma-derived cases (trauma group) and 10 caries-derived cases (caries group). Microbial samples were collected using sterile paper points inserted into the root canal exudate, followed by DNA extraction and Illumina sequencing of the hypervariable V3-V4 regions of the 16S rRNA gene. Bioinformatic analyses included α-diversity, β-diversity based on Bray-Curtis distance and differential abundance testing (LEfSe method with LDA score ≥ 2.0).

Results: Sequencing revealed 36 bacterial phyla and 587 genera across all samples. Trauma group showed significantly greater relative abundance of Campylobacter (P = 0.002) compared to caries group, whereas Prevotella (P = 0.008), Vibrio (P = 0.041) and Filifactor (P = 0.006) exhibited reduced abundance. The core microbiota in the trauma group included Phocaeicola, Porphyromonas and Pyramidobacter, based on relative abundance. LEfSe analysis identified Campylobacter as a biomarker for the trauma group.

Conclusions: Trauma-derived periapical lesions exhibited reduced microbial diversity compared to caries-derived periapical lesions, with Campylobacter identified as a potential pathognomonic taxon for trauma-derived periapical lesions.