齿龈内阿米巴引起牙周炎的实验研究

目的　探讨齿龈内阿米巴 (Entamoeba ,gingivalis ,E .g .)的致病性及其与牙周炎之间的关系。方法　大白鼠用免疫抑制剂处理 1周 ,其下颌中切牙颈部用不锈钢丝栓扎后 ,随机分为 3组 ,分别于牙龈涂拭E .g .,共生菌 (Symbioticbacteria ,S .b .)及生理盐水 ,观察各组大白鼠发生牙周炎状况 ,同时检查脓液中有无活的病原体 ,实验结果进行病理学分析。结果　E .g .组大白鼠牙周炎发病率高于S .b .组和对照组 (P <0 .0 5 ) ,S .b组大白鼠牙周炎发病率高于对照组 (P <0 .0 5 ) ;脓液镜检或培养均查见相应的病原体 ;病理证实E .g .可引发牙周炎。结论　E .g .是条件致病病原体 ,当宿主免疫力低下时 ,在口腔内细菌协同作用下可使宿主发生牙周炎。

Experimental study on the periodontitis cause by Entamecba gingivalis

Objective To investigate the pathogenicity of Entamoeba gingivalis(E.g.)and its relation to periodontitis.Methods After rats had been treated with immuno-inhibitor for one week,and then the neck of mandibular central incisar were ligated with stainless steel wire,they were divided into three groups random sampling.Rat's periodontal tissue of the first group were infected by E.g.The second group were infected by Symbiotic bacteria(S.b.).The third group were treated with physiological saline.Then we observed the conditions of periodontal inflammation in every group of rats and examined the purulent secretion from periodontal abscess to determine whether it has the living pathogens or not.The effects of the experiment were evaluated with pathological examination.Results The incidence of periodontitis in rats infected by E.g. was higer than that of S.b. group and that of control group(P<0.05),the incidence of periodontitis in rats infected by S.b. was higher than that of control group(P<0.05).The living pathogens could be found in the abscess liquid.Pathological examination proved that E.g. could cause periodontitis.Conclusion E.g. is an opportunistic pathogen,which,together with synergistic intraoral S.b. can cause periodontitis in hosts with low immunity.