Oxidative stress burden in endodontic infection: Gingival crevicular fluid 8-isoprostane in hypertensive patients with symptomatic apical periodontitis cross sectional observational study.

INTRODUCTION: Hypertension and endodontic infection may share oxidative stress-mediated mechanisms. This cross-sectional observational study compared gingival crevicular fluid (GCF) 8-isoprostane levels across healthy controls, hypertensive patients, systemically healthy patients with pulp necrosis and symptomatic apical periodontitis (SAP), and hypertensive patients with pulp necrosis and SAP. METHODS: Two hundred participants were classified into 4 groups (n = 50/group). GCF samples were collected and 8-isoprostane was quantified using enzyme-linked immunosorbent assay. Categorical variables were analyzed using the chi-square test. Between-group differences in 8-isoprostane were assessed using one-way ANOVA (Welch ANOVA when indicated) and analysis of covariance (ANCOVA) adjusting for age and sex; pairwise comparisons used Dunnett T3. RESULTS: GCF 8-isoprostane differed significantly among groups. Mean ± SD concentrations were 112.58 ± 10.85 pg/mL in controls, 237.42 ± 37.93 pg/mL in hypertensive patients, 201.36 ± 13.81 pg/mL in pulp necrosis with SAP, and 239.41 ± 21.52 pg/mL in hypertensive patients with pulp necrosis and SAP. Each disease group exhibited higher 8-isoprostane than controls (all P < 0.001). After adjustment for age and sex, the overall group effect remained significant (ANCOVA P < 0.001). Adjusted estimated marginal means showed no difference between hypertension alone and hypertension plus SAP (P = 1.000). CONCLUSIONS: GCF 8-isoprostane is elevated in hypertension and SAP relative to healthy status, independent of age and sex. Among hypertensive individuals, concomitant SAP was not associated with additional elevation, supporting GCF 8-isoprostane as a biomarker candidate reflecting oxidative stress burden in these conditions.