Abstract: Objective To study the reproduction method of experimental gingivitis and the objective indication for evaluation of the level of inflammation in rat．Methods The animal model of gingivitis was reproduced by suturing the neck of teeth and feeding of high sugar diet in rat．Local blood flow and crevicular fluid aspartate aminotransferase levels were evaluated by the 7th day after operation．Results The gingiva showed red and swelling and the superficial periodontal pocket formed in the rat of model group．The quantity and velocity of local blood flow increased in the model group．Cell number in blood flow significantly increased(P<0．05)．The level of aspartate aminotransferase in crevicular fluid dramatically increased(P<0．00 1)in comparison of control group．Conclusion This is a reliable animal model of gingivitis．Local blood flow and crevicular fluid aspartate aminotransferase level are sensitive indication for the rat model of gingivitis．

Key words: gingivitis, animal model, local blood flow, crevicular fluid aspartate aminotransferase

摘要： 目的对大鼠牙龈炎动物模型及炎症程度的评定指标进行研究。方法采用丝线缝扎大鼠牙颈部，辅以高 糖饮食造成牙龈炎模型，7 d后测定牙龈局部血流及龈沟液天冬氯酸转氨酶(AST)含量的变化。结果模型动物 牙龈充血红肿有溃疡和浅牙周袋形成。牙龈炎局部血流量和血流速度有一定程度的增加，但血细胞数升高更加显 著(P<0．05)．龈沟液AST较对照组有极显著的升高(P<0．001)。结论该模型为良好的牙龈炎动物模型，龈沟 液AST及局部微血流的改变均是反映牙龈炎发病程度的客观评定指标。

关键词: 牙龈炎, 动物模型, 局部血流, 龈沟液天冬氨酸转氨酶