RESUMEN
AIMS: To investigate, using a cross-sectional study design, whether the extent of periodontal inflammation associates with the serum levels of cytokine interleukin (IL)-10 and tumour necrosis factor (TNF)-α and their ratio. MATERIAL AND METHODS: The study group consisted of 61 subjects with chronic periodontitis and 30 control subjects with minimally inflamed periodontal tissues. Probing pocket depth (PD), bleeding on probing (BOP) and periodontal attachment level (AL) were measured. The serum IL-10 (pg/ml) and TNF-α (U/l) levels were analysed using enzyme-linked immunosorbent assays. After categorization of the subjects, associations between serum IL-10 and TNF-α levels and the extent of periodontal inflammation were studied using linear regression models adjusted for age, gender, body mass index and smoking. RESULTS: A negative, partly dose-dependent association existed between the extent of BOP, PD ≥ 4 mm and AL ≥ 4 mm and serum IL-10 level. The subjects in the periodontitis group presented significantly higher serum TNF-α levels and their TNF-α/IL-10 ratio was approximately threefold when compared with the ratio in the control group. CONCLUSIONS: The significantly higher serum TNF-α/IL-10 ratio in the subjects with chronic periodontitis when compared with the ratio in the controls is indicative of a stronger systemic pro-inflammatory state in chronic periodontitis.