Interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), nuclear factor kappa beta (NKFβ), osteoprotegerin (OPG), receptor activator nuclear factor kappa (RANK) and soluble receptor activator nuclear factor kappa ligand (sRANKL) as a potential diagnostic biomarker for peri-implant-diseases

Peri-implant diseases, including peri-implant mucositis and peri-implantitis, pose a growing challenge to the long-term success of dental implants. Early diagnosis and effective management of these conditions are essential to preserve their functions and prevent failure. This study evaluated the potential of IL-6, TNF-α, NFκβ, OPG, RANK and sRANKL in peri-implant crevicular fluid (PICF) as potential diagnostic tools for peri-implant diseases. These biomarkers were selected due to their important roles in inflammatory processes and bone metabolism, which are central to the pathogenesis of peri-implant diseases. A prospective study was conducted involving 21 patients with 32 dental implants. Based on the clinical examinations and radiographical evaluation, the dental implants were categorised into peri-implant health (PH), peri-implant mucositis (PM), and peri-implantitis (PI) groups. Clinical parameters recorded in this study were probing pocket depth (PPD), full-mouth bleeding score (FMBS), full-mouth plaque score (FMPS), modified plaque index (mPI), and modified bleeding index (mBI). PICF samples were collected using standardised PerioPaper strips. Both clinical parameter measurement and PICF sample collection were done at baseline and after 3 months of non-surgical periodontal therapy (NSPT). NSPT was conducted only to reduce peri- implant inflammatory levels and to see any changes in the biomarker concentration. The PICF samples were then analysed and quantified using the ELISA test. Statistical analyses were performed to compare the concentrations of biomarker levels between groups and to discern intergroup differences before and after NSPT to allow the assessment of the changes in biomarker concentration after NSPT. The results revealed that IL-6, TNF-α, NFκβ, RANK, and sRANKL were detectable in all three groups of peri-implant conditions. Statistical significance was also seen in the concentrations of RANK and IL-6 (p > 0.05) when intergroup comparisons were made comparing PI to PM and PH. Significant reductions in concentrations of IL-6, TNF-α, NFκβ, RANK, and sRANKL were also observed after three months of NSPT (p < 0.05). Heterogeneity of results was observed where statistical significance was only seen in the PH group involving TNF-α and sRANKL (p < 0.05). In contrast, statistical significance was noted in PM and PI in IL-6, NF-κB, and RANK (p < 0.05). However, despite numerical reduction across all groups post-treatment, OPG did not show any significant statistical changes (p > 0.05). Significant improvement of PPD, mPI, and mBI was seen involving PH (p < 0.05), and both PH and PM showed significant improvement of FMBS and FMPS (p < 0.05). This study underscores the potential of PICF biomarkers as valuable tools for early detection and monitoring of peri-implant diseases. The findings also suggest that NSPT effectively reduce inflammation and improves clinical outcomes in peri-implant mucositis; however, peri-implantitis cases require surgical approaches in addition to NSPT. Incorporating biomarkers in addition to the standard practice of diagnosis may facilitate earlier detection of peri‐implant disease progression and enable more targeted, individualised therapeutic strategies.