Osteoblast apoptosis in experimental diabetic periodontitis in rats

To observe osteoblast apoptosis in diabetic periodontitis. Sixty-two SD rats were randomly divided into three groups: Diabetic periodontitis group (DP), periodontitis group (P) and normal control group (N). Diabetes was induced by intraperitoneal injection of streptozotocin (STZ). Periodontitis was initiated by ligating floss around maxillary second molars and inoculation of Porphyromonas gingivalis (P. gingivalis). Three or six weeks later, the animals were sacrificed and the specimens were prepared for histological analysis. The percentage of apoptotic osteoblasts was examined. Statistical significance was determined by one-way ANOVA. The sequence of percentage of apoptotic osteoblasts among each group was group DP > group P > group N. Intergroup comparisons demonstrated that diabetic periodontitis and periodontitis might increase apoptosis of osteoblasts. The percentage of apoptotic osteoblasts in group DP was approximately two times higher than that in group P. The present study clearly demonstrates that