[Interleukin-1beta and IL-1 receptor antagonist levels in gingival crevicular fluid and their relationship to clinical indices of periodontitis].

OBJECTIVE

To investigate Interleukin-1beta (IL-1beta) and IL-1 receptor antagonist (IL-1ra) concentrations in gingival crevicular fluid (GCF) of periodontally healthy teeth and to periodontitis teeth and to reveal their relationships to periodontal clinical indices.

METHODS

Thirty GCF samples were harvested from periodontally healthy sites in which 15 samples were from periodontally healthy subjects and 15 GCF samples were from patients with chronic periodontitis, and 43 GCF samples (including 28 samples from BOP positive sites and 15 samples from BOP negative sites) were harvested from periodontitis sites of 33 patients with chronic periodontitis. Clinical indices (GI, PPD and CAL) were recorded for each tooth. The concentrations of IL-1beta and IL-1ra in GCF were quantified by ELISA method.

RESULTS

(1) The mean concentrations of IL-1beta and IL-1ra and the average value of 10(4)IL-1beta/IL-1ra for periodontally healthy teeth were (61.891 +/- 20.719) pg/ml, (739.410 +/- 249.121) ng/ml and 0.857 +/- 0.375, respectively. The mean concentration of IL-1beta (224.402 +/- 87.416) pg/ml and the average value of 10(4)IL-1beta/IL-1ra for periodontitis teeth 6.813 +/- 0.375 were greater than those for healthy teeth, respectively (P<0.0001), and in contrast, the mean concentration of IL-1ra for periodontitis teeth (366.722 +/- 104.188) ng/ml was lower than that for healthy sites(P<0.0001). (2) For all sites, a strong inverse relationship was found between IL-1beta and IL-1ra levels in GCF (P<0.01). Both of IL-1beta and 10(4) IL-1beta/IL-1ra values had positive correlations with GI, PPD and CAL (P<0.01). And the negative correlation was found between GI and IL-1ra (P<0.05). (3) The mean concentration of IL-1beta and the average value of 10(4)IL-1beta/IL-1ra at BOP positive teeth were greater than those at BOP negative teeth (P<0.0001), and the mean concentration of IL-1ra at BOP positive teeth was lower than that at BOP negative teeth (P<0.01).

CONCLUSION

The results suggest that the increasing GCF level of IL-1beta and decreasing level of IL-1ra may be an important factor for the pathogenesis and development of chronic periodontitis and IL-1ra has an inhibitory effect on IL-1beta activity. The GCF level of IL-1beta and the value of 10(4)IL-1beta/IL-1ra, especially the latter one, are closely associated with the clinical indices of chronic periodontitis.