Useful immunochromatographic assay of calprotectin in gingival crevicular fluid for diagnosis of diseased sites in patients with periodontal diseases

Abstract Background Calprotectin, an inflammation‐related protein, is present in gingival crevicular fluid (GCF), and the determination of calprotectin is useful for diagnosing periodontal diseases. The authors have recently developed a novel immunochromatographic (IC) chip system to determine calprotectin levels in GCF. In the present study, the usefulness of this diagnostic system is investigated in patients with periodontal diseases. Methods Thirty‐six patients with periodontal diseases participated in this clinical test at multiple centers. Periodontitis sites (n = 118) and non‐periodontitis (healthy) sites (n = 120) were selected after periodontal examination. GCF collection and periodontal examination were performed at baseline, after supragingival and subgingival scaling and root planing. Calprotectin levels in GCF were determined using a novel IC chip system and evaluated as a visual score and an IC reader value. Correlations between GCF calprotectin levels, clinical indicators, and changes in cal...