A method for the detection of prostaglandin E (PGE) in crevicular fluid has been developed which provides a sensitive, noninvasive technique for measurement of local concentrations of this mediator of inflammation. Assay sensitivity sufficient for the detection of 4 picograms of PGE2 was achieved by utilizing a high-affinity anti-PGE2 antibody, a solid-state second antibody and low isotope concentrations. The method permits detection of concentrations equivalent to 10(-8) M PGE2 in 1 microliter of crevicular fluid. Crevicular fluid PGE (CFPGE) concentrations were determined in samples from 12 patients with periodontal disease. Patients with periodontitis had significantly higher mean CFPGE concentrations than patients with gingivitis (179.5 +/- 51.4 pg/microliter vs 32.1 +/- 15.5 pg/microliter, mean +/- SEM). Periodontitis sites were selected on the basis of clinical and radiographic evidence of periodontal destruction. Some sites displayed low CFPGE levels, while others had CFPGE concentrations which were elevated tenfold, suggesting the presence of both inactive and active periodontal lesions. CFPGE levels greater than 100 pg/microliter were positively associated with gingival erythema and pain on probing.