Effects of ketorolac tromethamine mouthrinse (0.1%) on crevicular fluid prostaglandin E2, concentrations in untreated chronic periodontitis

The effects of topical ketorolac tromethamine mouthrinse (0.1%) on gingival crevicular fluid (GCF) prostaglandin E-2 (PGE(2)) concentrations were investigated in a 6-week, randomized, double-blind, placebo-controlled, parallel group, single center study of 42 patients with moderately advanced chronic adult periodontitis. Following screening, GCF was sampled from 6 sites per subject with filter paper strips and PGE(2) levels measured using an enzyme immunoassay kit. Only those subjects with mouth median GCF PGE(2) concentrations >30 ng/ml entered the rinsing phase. Eligible subjects were allocated placebo rinse in the first 2-week period (days 0 through 14), either ketorolac rinse (test group, n = 21) or placebo rinse (control group, n = 21) in the second 2-week period (days 14 through 28), and placebo rinse in the third 2-week period (days 28 through 42). Full mouth median GCF PGE(2) concentrations were calculated for each subject at days 0, 14, 28, and 42, and group means were compared. From day 0 to day 14, no significant changes in GCF PGE(2) concentrations were detected in either study group (P > 0.05). Utilizing mean GCF PGE(2) concentrations at days 0 and 14 as covariates, no significant differences were observed in adjusted mean PGE(2) levels at days 28 and 42 between the study groups (ANCOVA, P > 0.05). A statistically significant increase in GCF PGE(2) levels was noted at days 28 and 42 in the placebo group (P < 0.01), but not in the ketorolac group (P > 0.05), when compared to baseline, however. GCF PGE(2) levels were further studied in a subset of volunteers (n = 11) during a 12-hour period following first rinsing with mouthrinse (active or placebo) at day 14. GCF was sampled 0, 2, 4, 6, 8, and 12 hours post rinsing. Mean PGE(2) levels were higher in the placebo subgroup than in the ketorolac subgroup, and increased gradually over the 12-hour period in both subgroups. These data indicate that 1) 14 days of rinsing with 0.1% ketorolac mouthrinse controlled the elevation of GCF PGE(2) observed in the placebo group but did not actually reduce GCF PGE(2) concentrations and 2) changes in GCF PGE(2) levels were not detectable in the 12-hour period following first rinsing with ketorolac.