Objective  To investigate the effect of periodontal infection on circulating C-reactive protein（CRP） in type 2 diabetes patients. Methods  32 diabetes patients

with advanced periodontitis participated in this study. They were compared to a group of 32 diabetes patients without periodontal disease, who were mathed with regard to age（±3 years）, gender and body mass index（±1 kg/m2）. The concentration of CRP on circulation was measured by ELISA.
Results  Significant difference was found in the level of CRP and the percentage of subjects with elevated CRP levels≥3 mg/L on circulation between the two groups （P<0.05）. Conclusion  Periodontal infection results in higher circulating CRP in type 2 diabetes patients. This elevated inflammatory factor may exacerbate insulin resistance and increase the risk for great vessels complications of  diabetes mellitus．