MATERIALS AND METHODS: Forty chronic periodontitis patients completed this study and received periodontal treatment comprising scaling and root planing plus ultrasonic debridement. Clinical data were recorded at baseline, 6 weeks (R1) after treatment completion (full-mouth or quadrant-scaling and root planing) and 25 weeks after baseline (R2). Serum samples were taken at each time point and cytokines concentrations determined by ELISA.

RESULTS: Following treatment, statistically significant reductions were noted in clinical parameters. However, IL-17A and IL-17E concentrations were significantly greater than baseline values before- and after-adjusting for smoking. The IL-17A:IL-17E ratio was lower at R1 and R2. Serum IL-6 and TNF levels were significantly lower at R1 only. Also exclusively at R1, serum IL-17A and IL-17E correlated positively with clinical parameters, while the IL-17A:IL-17E ratio correlated negatively with probing pocket depth and clinical attachment.

CONCLUSION: Increased serum IL-17E and a reduced IL-17A:IL-17E ratio may be indicative and/or a consequence of periodontal therapy. Therefore, the role of IL-17E in periodontal disease progression and the healing process is worthy of further investigation.