中文摘要：

目的：通过建立大鼠实验性牙周炎模型,检测不同时段大鼠上颌第一磨牙龈下人工定植的牙龈卟啉单胞菌、牙龈素rgpB和kgp相对含量的改变,动态观察牙周炎发展不同阶段牙龈卟啉单胞菌致病基因的变化。方法：选择6周的成年雄性大鼠13只,应用钢丝结扎法和细菌种植法建立大鼠实验性牙周炎模型。分别在4周和8周取上颌第一磨牙龈下菌斑,提取细菌DNA,应用PCR方法进行牙龈卟啉单胞菌、牙龈素基因rgpB和kgp特异引物扩增,应用SPSS13.0统计软件,分析大鼠牙周炎不同时段rgpB和kgp的相对变化。结果：大鼠实验性牙周炎模型,龈下菌斑中牙龈卟啉单胞菌的相对含量实验组明显高于对照组,8周组高于4周组;实验组牙龈卟啉单胞菌牙龈素rgpB和kgp明显高于对照组,4周组和8周组rgpB和kgp相对含量无显著性差异。结论：rgpB基因和kgp基因与牙周炎的致病性有关而与牙周炎的严重程度可能无直接相关。

英文摘要：

Objective： To test the relative content changes of P.gingivalis inoculating to subgingival of first maxillary molars of the rats in different times and the changes of gingipians gene rgpB and kgp by establishing periodontitis model.Methods： We selected 13 six-week adult male rats and established the periodontitis model by ligating steel-wire and bacterial inoculation.We took the subgingival plaque,then extracted DNA and operated the PCR amplification by using the specific primer.We analyzed the genetic changes of rgpB and kgp in different stages of the rat periodontitis by using SPSS13.0 two independent t test sample analysis.Results： The relative content of P.gingivalis in the experimend groups was significantly higher than that in the control groups,while the relative contents of rgpB and kgp between 4 weeks and 8 weeks were no significant differences.Conclusion： RgpB gene and kgp gene may relative to the pathogenicity of periodontitis,but have no direct relevant to the severity of periodontal disease.