Analysis of Biomarkers and Marginal Bone Loss in Platform-Switched and Nonplatform-Switched Implants: A Randomized Clinical Trial

OBJECTIVES: To compare the peri-implant crevicular fluid (PICF) biomarker levels, peri-implant status, and marginal bone level (MBL) differences of implants restored with randomly assigned nonplatform-switched (NPS) or platform-switched (PS) abutments. METHODS: Ninety-four implants in 27 subjects were included in this study. Receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG), interleukin-1β (IL-1β), monocyte chemotactic protein-1 (MCP-1) levels in PICF, peri-implant health, and the change in the MBL were evaluated at the time of restoration (T(1)) and after 12 months (T(2)). RESULTS: The IL-1β levels decreased and the RANKL, OPG, and MCP-1 levels increased from T(1) to T(2) (P < 0.05) in both groups. RANKL/OPG ratio at T(1), MCP-1 levels at T(2), and the MCP-1 change from T(1) to T(2) were lower in the PS group than in the NPS group (P < 0.05). MBL change was lower (0.51 ± 0.31 mm) in the PS group than that (0.75 ± 0.29 mm) in the NPS group at T(2) (P < 0.001). Peri-implant health status between the study groups was negligible. CONCLUSION: PS was superior to NPS regarding the preservation of MBL. Higher MCP-1 levels, altered RANKL/OPG ratio, and lower OPG levels in the NPS group could be associated with subclinical peri-implant bone remodeling.