Peri-implant Sulcular Fluid Galectin-1, Soluble Urokinase Plasminogen Activator Receptor and IL-1β Levels under Peri-implant Inflammatory Conditions

Purpose: Soluble urokinase plasminogen activator receptor (suPAR) and interleukin 1-beta (IL-1β) are inflammatory biomarkers, whereas galectin-1 is an anti-inflammatory cytokine. The relationship between suPAR, galactin-1 and IL-1β levels in peri-implant sulcular fluid (PISF) in relation to dental implants remains unaddressed. The aim was to assess suPAR, galectin-1, and IL-1β levels in PISF under peri-implant inflammatory conditions.
Materials and Methods: Demographic data and information related to jaw location and duration of implants in function as well as systemic health was retrieved from patients’ dental records. Peri-implant plaque and gingival indices (PI and GI, respectively), probing depth (PD) and crestal bone loss (CBL) were recorded. The PISF was collected and levels of suPAR, galectin-1 and IL-1β were determined using standard techniques. Sample-size estimation and statistical analyses were done. Correlation of suPAR and galectin-1 with IL-1β were assessed via logistic regression. p-values < 0.05 were considered statistically significant.
Results: Seventy-two patients (45 males and 27 females) with peri-implant diseases were included. Thirty-six patients (22 males and 14 females) had peri-implant mucositis; 36 (23 males and 13 females) had healthy peri-implant tissues. The PISF volume was statistically significantly higher among patients with (0.52 ± 0.05 µl) than without peri-implant diseases (0.06 ± 0.01 µl) (p < 0.001). The PISF levels of suPAR (p < 0.01), galectin-1 (p < 0.01) and IL-1β (p < 0.01) were statistically significantly higher among patients with than without peri-implant diseases. In patients with peri-implant mucositis, PISF suPAR (p < 0.001) and galectin-1 (p < 0.001) levels correlated with PISF IL-1β levels. In patients with peri-implant mucositis, increasing peri-implant PD and IL-1β levels directly correlated with increased PISF suPAR (p < 0.001) and galectin-1 (p < 0.05) levels.
Conclusion: Increased PISF levels of suPAR, galectin and IL-1β suggest that these proteins possibly contribute towards the pathogenesis of peri-implant inflammation, and are potential biomarkers of peri-implant diseases.