Abstract: PURPOSE: To investigate the changes of IL-27 in gingival crevicular fluid (GCF) before and after treatment with different methods for chronic periodontitis. METHODS: Sixty patients with moderate or severe chronic periodontitis were selected as study group to divide into group A (cross-quadrant) and group B (upper and lower half-mouth) randomly. Another 30 healthy people were selected as group C. Gingival crevicular fluid of group A and B were collected at baseline and each week during treatment. At the same time, the clinical parameters including PD, AL, BI and PLI were recorded. And the levels of IL-27 in GCF were measured by ELISA. SPSS 17.0 software package was used for statistical analysis. RESULTS: The levels of IL-27 in GCF 2 and 3 weeks after treatment were higher in study group compared with those at baseline, while PD, AL, BI and PLI showed significant reduction. The changes except PLI in group A was more obvious than group B, which had a significant difference. After three-week treatment, IL-27 in group A had no remarkable difference compared with group C. There were significantly negative correlation between PD, AL, BI, PLI and IL-27. CONCLUSIONS: IL-27 in GCF can be considered as a potential target for prevention and treatment of chronic periodontitis. Compared with the upper and lower half-mouth subgingival scaling, cross-quadrant has more pronounced short-term effect.

Key words: Periodontitis, Gingival crevicular fluid, IL-27, Cross-quadrant subgingival scaling