Objective To detect Porphyromonas gingivalis(P.gingivalis) in the carotid artery of rats with chronic periodontitis and to explore the possible relationship between P.gingivalis and chronic periodontitis. Methods Fortytwo SD rats were randomly divided into six groups: Group A(control group), group B1(non-intervention group), group B2(scaling and root planning group), group B3(systemic antibiotics group), group B4(tooth extraction group), and group B5(tooth extraction with antibiotics for 3 d). Each group accepted the corresponding measures and periodontal interventions to establish the animal model. After the death of experimental animals, P.gingivalis was semi-quantitatively detected in the right carotid artery tissue by 16S rRNA polymerase chain reaction. Results P.gingivalis was detected in all groups. The relative quantity of P.gingivalis significantly increased in groups B1 to B5 compared with that in group A(P
