Elevated Cytokine Levels in Gingival Crevicular Fluid of Teeth with Apical Periodontitis

Biomarkers assayed from gingival crevicular fluid (GCF) are a potential tool for endodontic diagnosis and for monitoring treatment response. This cross-sectional study measured cytokines in GCF from teeth with apical periodontitis and evaluated their relationship with preoperative pain and other clinical findings.

Participants presenting for root-end resection surgery due to apical periodontitis diagnosis (n = 56) underwent standardized clinical testing and completed preoperative questionnaires. GCF from diseased and control teeth were collected, processed, and analyzed. Mann-Whitney U and Wilcoxon tests were used to examine the cytokine levels in diseased compared to healthy control teeth. We also assessed the relationship of cytokine levels with clinical findings.

Interleukins (IL)-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, interferon-γ, and tumor necrosis factor-⍺ (TNF-⍺) were detected in GCF. TNF-⍺ levels were significantly higher in GCF collected from diseased versus control teeth (P = .02) and increased IL-1β levels in diseased teeth were detected (P = .06). Lower IL-10 levels were observed in teeth with a sinus tract and/or swelling compared to teeth without a sinus tract and/or swelling (P = .08). Cytokine levels did not clearly relate to the presence of pain.

Elevated levels of proinflammatory cytokines, including TNF-⍺ and IL1- β, were detected in GCF from diseased teeth compared to the healthy controls. Additional studies are needed to further investigate the utility of these biomarkers for objectively evaluating periradicular pathology.