Comparison of mRNA expression levels in peri-implantitis and periodontitis within the same host environment

Purpose: The aim of this study was to explore whether differences exist and to what an extent of the immune-mediated inflammatory reactions between periodontitis and peri-implantitis at the transcriptional level in the same susceptible host. Methods: Ligature-induced experimental peri-implantitis and periodontitis in the same mice were established. Gingival tissues of healthy, periodontitis and peri-implantitis sites from the same oral cavity were collected and used for RNA-sequencing. Differentially expressed genes (DEGs) were screened between periodontitis/peri-implantitis sites and healthy sites. The enrichment analysis of DEGs were analyzed. Comprehensive immune landscape was annotated by seq-ImmuCC. Results: The results showed that 137 and 353 up-regulated DEGs as well as and 670 and 174 down-regulated DEGs were specifically expressed periodontitis/peri-implantitis group compared to the healthy control group, respectively. The pathways of complement and coagulation cascade and osteoclast differentiation were dominating in the peri-implantitis sites. Moreover, peri-implantitis sites exhibited elevated macrophage proportions and relatively enriched macrophage activation and bone loss compared with periodontitis. Conclusions: Results indicated that peri-implantitis and periodontitis exhibited significantly distinct transcriptional signatures. Additionally, the study suggests that the interplay between macrophages and bone resorption are comparatively more active in peri-implantitis compared with periodontitis. These biological processes may be factors contributing to the pathogenesis of peri-implantitis being distinct from that of periodontitis. Gingival tissues of healthy, periodontitis and peri-implantitis sites from same mice (n=3) were included, and these tissues were sent to the Majorbio Technology Co., Ltd. (Shanghai, China) for sequencing.