Background: Tumor necrosis factor-alpha (TNF-alpha) may play an important role in insulin resistance. In this study, we hypothesized that TNF-alpha produced due to periodontal inflammation synergistically affects insulin resistance as well as TNF-alpha produced from adipose tissues in insulin-resistant type 2 diabetes patients. Therefore, to understand the effects of antimicrobial periodontal therapy on serum TNF-alpha concentration and subsequent metabolic control of diabetes, we examined the periodontal and diabetic status on 13 type-2 diabetes patients.
Methods: These patients were treated with local minocycline administration in every periodontal pocket around all existing teeth once a week for a month. Before and after treatment, the number of total bacteria in the periodontal pockets and circulating TNF-alpha concentration were measured and the HbA1c value was assessed.
Results: Antimicrobial therapy significantly reduced the number of microorganisms in periodontal pockets (P <0.01). After treatment, the circulating TNF-alpha level was significantly reduced (P <0.015). The HbA1c value was also reduced significantly (P <0.007). In addition, the 6 patients who were not receiving insulin therapy demonstrated decreased fasting insulin levels (P <0.03), and HOMA-R (P <0.03) indices. The average reductions in circulating TNF-alpha concentration and HbA1c value were 0.49 pg/ml and 0.8%, respectively.
Conclusion: The results indicate that anti-infectious treatment is effective in improving metabolic control in diabetics, possibly through reduced serum TNF-alpha and improved insulin resistance.