Immunodiagnostic potential of the RANK/RANKL/OPG ratio in gingival crevicular fluid for periodontitis

Abstract

Introduction: Periodontitis and apical periodontitis are multifactorial inflammatory diseases involving microbial activity and host responses that lead to tissue destruction. Biomarkers such as receptor activator of nuclear factor-kappa B (RANK), its ligand (RANKL), and the osteoprotegerin (OPG) system in gingival crevicular fluid (GCF) have been investigated for their diagnostic and prognostic roles in these conditions. Aim: This study evaluates these biomarkers’ levels to differentiate between stage I and stage III periodontitis, and healthy controls. Materials and methods: This cross-sectional study included 90 participants divided into three groups: stage I periodontitis, stage III periodontitis, and healthy control. GCF samples were collected from all participants in this study to measure the immunomarkers using ELISA. Results: The result revealed significantly higher levels of RANKL and OPG in stage I periodontitis compared to stage III periodontitis and controls. Additionally, we observed a significant difference between the study groups in the RANK/OPG and RANKL/OPG ratios, with stage I periodontitis showing the highest ratios. Conclusion: This study demonstrated that the levels of receptor activator of nuclear factor-kappa B (RANK), its ligand (RANKL), and osteoprotegerin (OPG) in the gingival crevicular fluid (GCF) can serve as valuable biomarkers for distinguishing between stage I and stage III periodontitis. The results showed a significant increase in RANKL and OPG levels in stage I periodontitis compared to stage III and control groups. Moreover, the RANK/OPG and RANKL/OPG ratios were significantly higher in stage I periodontitis, indicating their potential as diagnostic indicators.