Levels of Leukotriene B4 in Gingival Crevicular Fluid and Gingival Tissue in Specific Periodontal Diseases

Background: Leukotriene B4 (LTB4), a product of the lipoxygenase pathway of arachidonic acid metabolism, exhibits numerous activities that can account for most of the features of host responses seen in periodontal diseases. The aim of the present study was to examine the role of LTB4 in the pathogenesis of specific periodontal diseases. Methods: LTB4 levels were investigated in gingival crevicular fluid (GCF) and gingival tissue (GT) samples of 10 patients with chronic periodontitis (CP), 12 patients with generalized aggressive periodontitis (GAgP), 6 patients with localized aggressive periodontitis (LAgP), 6 patients with gingivitis (G), and 6 periodontally healthy subjects (H). Periodontal status was evaluated by measuring probing depth, gingival index, papillary bleeding index, and plaque index. LTB4 was extracted from the samples by solid‐phase method using C18 cartridge and was purified by high performance liquid chromatographic method and then analyzed by radioimmunoassay. Results: All patient groups had significantly higher levels of GCF and GT LTB4 compared to the control group (P 0.005). The CP group had higher LTB4 concentration compared to both GAgP and LAgP groups (P 0.005). No significant correlation was found between GCF and GT LTB4 levels and clinical parameters. Conclusions: The results of the present study indicate that LTB4 is likely to be an important mediator in regulating inflammatory responses in the human periodontal tissues. This lipid mediator may play an important role in the pathophysiology of periodontal disease. J Periodontol 2001;72:1025‐1031.