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

Abstract

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 ( $0.51\pm 0.31$  mm) in the PS group than that ( $0.75\pm 0.29$  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.