Recent studies have shown that cytokines are pivotal to the pathogenesis of periodontal diseases and may be used as markers in diagnosis.

The aim of the present study was to determine the levels of interleukin (IL)-1beta, IL-4, IL-6 and IL-8 in gingival crevicular fluid of periodontally healthy and diseased individuals and to study their association to smoking, stress and clinical periodontal parameters.

A total of 80 patients were included in the study : 20 patients with early onset or aggressive periodontitis (EOP), 20 with chronic adult periodontitis (AP), 20 with gingivitis (G) and 20 patients with healthy periodontium (H). GCF was collected by means of Durapore strips, from four sites per patient, randomly selected in each quadrant. The contents of IL- 1beta, IL-4, IL-6 and IL-8 were measured in 320 samples by use of commercially available sandwich enzyme-linked immunoadsorbent assays.

In periodontally diseased subjects the total amounts of IL-1beta, IL-6 and IL-8 were significantly elevated as compared to healthy subjects, whereas IL-4 showed an inverse relationship to periodontal status and higher amounts were found in the healthy group. The amounts of all four cytokines were positively correlated with probing depths. IL-4, IL-6 and IL-8 were significantly correlated to smoking while stress was associated with IL-1beta, IL-6 and IL-8 levels.

The present data suggest that crevicular IL-1beta, IL-6 and IL-8 reflect the activity of periodontal destruction, whereas IL-4 shows an inverse correlation to it. The enhanced production of inflammatory cytokines in the presence of smoking and stress may have clinical consequences.