Gingival crevicular fluid as a source of biomarkers for periodontitis

Abstract

In evaluating the pathogenesis of periodontal diseases, the diagnostic potential of gingival crevicular fluid has been extensively explored during the last twenty years, from initially just confirming health and disease states to more recently investigating it as a potential prognostic tool. As host susceptibility is a critical determinant in periodontal disease pathogenesis, the inflammatory mediator levels present in gingival crevicular fluid represent relevant risk indicators for disease activity. Considerable work has been carried out to identify the many different cytokine inflammatory pathways and microbial stimuli that are associated with periodontal disease pathogenesis. Now, 'omics' approaches aim to summarize how these pathways interact and probably converge to create critical inflammatory networks. More recently, gingival crevicular fluid metabolomics appears promising as an additional diagnostic method. Biofilm structure and the host inflammatory response to the microbial challenge may induce specific inflammatory signatures. Host genetics and epigenetics may also modulate microbial colonization, adding to the multiplicity of potential causal pathways. Omics analyses of gingival crevicular fluid, measuring microbial and host interactions in association with the onset and progression of periodontal diseases, still show the potential to expand the landscape for the discovery of diagnostic, prognostic and therapeutic markers.

Figure 1

Schematic figure indicating the flux of gingival crevicular fluid through epithelial cells in the presence of a biofilm. In this microenvironment the exudate contributes to reorganization of subgingival biofilm and also carries inflammatory mediators and inflammatory cells to the periodontal pocket while harboring bacterial antigens, and enzymes of both host and bacterial origin.

Figure 2

Ilustration of GCF sampling sequence and use of Periotron®. Once the sites are isolated with cotton rolls and gently air-dried, the Perio® paper strips are inserted in the gingival sulcus for 30 seconds. The paper strips are then inserted in the Periotron 8000® device (Harco, Tustin, CA, USA), previously calibrated to each individual sample to obtain the fluid volume. Paper strips are then wrapped in aluminum foil, transferred to liquid nitrogen and stored at −80°C until assayed.