Background: To determine the effect of non-surgical periodontal therapy on serum TNF-a and HbA1c levels in poorly and well-controlled type 2 diabetic patients. Methods: In total, 45 patients were enrolled in the study; 30 patients with type 2 diabetes mellitus with periodontitis (15 with poorly controlled diabetes, HbA1c ‡ 7%, group 1A and 15 with well-controlled diabetes, HbA1c < 7%, group 1B) and 15 patients that were systemically healthy with periodontitis (group 2). The plaque index, gingival index, probing depth, clinical attachment loss, gingival bleeding index, HbA1c value, and circulating TNF-a concentration were measured at baseline and three months after the non-surgical periodontal therapy. Results: All periodontal parameters and serum TNF-a levels were significantly decreased three months after the nonsurgical periodontal therapy compared to the baseline values in all groups. The HbA1c values were significantly decreased only in well-controlled diabetic patients. We found no significant differences in the periodontal parameters or TNF-a levels at baseline and after three months between the two groups. Conclusions: Although non-surgical periodontal therapy eliminates local ⁄ systemic infection and inflammation via decreases in TNF-a, it is insufficient for significantly reducing HbA1c levels without strict glycaemic control in poorly controlled diabetic patients in a short time period.

The levels of TNF-alpha and IL-8 in gingival crevicular fluid were significantly higher in HD patients than in controls. There were strong, positive correlations between clinical periodontal parameters and the levels of inflammatory cytokines in gingival crevicular fluid from the HD patients.