Aim: To quantify reduced and oxidized glutathione (GSH and GSSG) levels in gingival crevicular fluid (GCF) of periodontitis patients pre-therapy (versus periodontally healthy controls) and ascertain whether successful non-surgical therapy alters glutathione levels.
Materials and methods: Thirty-second GCF samples (6/subject) were collected on Periopaper() strips from starved, non-smokers (n=20; mean age 43.6 years) with chronic periodontitis, before and 3 months after non-surgical therapy, and periodontally healthy, age- and gender-matched controls (n=20). GSH and GSSG levels were determined using reversed-phase high-performance liquid chromatography with fluorescence detection.
Results: Lower concentrations of GSH (p<0.01) and GSSG (p<0.05) were detected in GCF from patients (pre- and post-therapy) than controls and treatment had no significant effect. Amounts per 30-second sample did not differ between patients and controls. However, the amount of GSSG per 30-second sample decreased in patients after therapy (p<0.05). Consequently, therapy increased the GSH:GSSG ratio (p<0.05) in patients compared with the controls (p=0.8).
Conclusion: These data demonstrate high concentrations of GSH within GCF, which are compromised in chronic periodontitis. While therapy does not appear to fully restore GSH concentrations in GCF, it does restore the redox balance (GSH:GSSG ratio), suggesting that the abnormal redox balance arises secondary to oxidative stress resulting from periodontal inflammation.