Estimation of Bone Loss Biomarkers as a Diagnostic Tool for Peri-Implantitis

Background: The aims of this study are to estimate the profile of bone loss biomarkers in peri-implant tissues and to identify potential prognostic biomarkers of peri-implantitis. Methods: Peri-implant crevicular fluid samples collected from 164 participants (52 patients with peri-implantitis, 54 with mucositis, and 58 with healthy peri-implant tissues) were analyzed using enzyme-linked immunosorbent assays to evaluate concentrations of the receptor activator of nuclear factor-kappa B (RANK), soluble RANK ligand (sRANKL), osteoprotegerin (OPG), cathepsin-K, and sclerostin. Results: Concentrations of RANK, sRANKL, OPG, and sclerostin were significantly increased in patients with peri-implantitis compared with patients with healthy peri-implant tissues. Comparisons between peri-implantitis and mucositis demonstrated significantly higher values of sclerostin in peri-implantitis samples. Comparisons between mucositis and healthy peri-implant tissues showed significantly increased levels of RANK and cathepsin-K in mucositis. Conclusion: These results are suggestive of a role of sRANKL, OPG, and sclerostin as prognostic biomarkers in peri-implantitis.