Towards a noninvasive diagnosis of Peri-implantitis: proteomic analysis of Peri-implant crevicular fluid

Peri-implantitis, the inflammatory process affecting both the soft and hard tissues surrounding dental implants, has a prevalence of approximately 20 %. In current clinical procedure, diagnosis of peri-implantitis relies on the detection of an increased periodontal pocket depth and the radiological recording of bone loss, both of which are symptoms of an already advanced stage of the disease. To date, neither the cause of the disease nor the mechanisms of its progression have been clarified, which makes adequate therapy a major challenge. Therefore, the detection of peri-implantitis is of great importance to prevent progression and to ensure long-term success of dental implants.

Crevicular fluid, localized in the gap between dental implants and the gingiva, was proposed as a noninvasive source for the identification of potential diagnostic, prognostic, or therapeutic markers in the field of periodontology and implantology. In this study, we used explorative LC-MS/MS analysis with a semi-automated sample preparation workflow to identify and quantify >3000 proteins, revealing distinct proteomic profiles for crevicular fluids of healthy and diseased dental implants. Among the upregulated proteins in peri-implantitis-affected implants are proinflammatory proteins, predominantly driven by neutrophil activity, and antimicrobial proteins. The crevicular fluid of diseased implants also exhibited higher abundances of semi-specific peptides, indicative of increased proteolytic activity.