Microbiological profile of peri-implantitis: Analyses of microbiome within dental implants.

PURPOSE To characterize the microbiome composition within dental implants of peri-implantitis subjects and healthy controls using 16S rRNA gene sequencing. MATERIALS AND METHODS  Twenty-three subjects with healthy (n = 11 implants) and diseased (peri-implantitis, n = 21) implants were included in this controlled clinical cross-sectional study. Samples were obtained from internal surfaces of dental implants using sterile paper points for microbiological analysis. DNA was extracted, and the16S rRNA gene was amplified using universal primers targeting the V3-V4 regions. The resulting 16S PCR amplicons were sequenced on Illumina MiSeq, and the sequences were processed using DADA2 and the Human Oral Microbiome Database (HOMD) as references. Alpha and Beta diversity, as well as core microbiome and differential abundance analyses were then performed using the MicrobiomeAnalyst workflow. RESULTS A significant increase in microbial diversity was observed in the internal implant surface of healthy implants compared with the internal surfaces of peri-implantitis (Shannon P = 0.02). Bacterial community structure was significantly different between groups (P = 0.012). High levels of Gram-positive bacteria were detected inside implants with peri-implantitis compared to healthy implants, especially Enterococci. CONCLUSIONS There is a shift in bacterial diversity inside implants with peri-implantitis from the healthy control. The microbial colonization within that space might contribute to the etiology of peri-implant disease. This article is protected by copyright. All rights reserved.