Specimens were taken from the tooth surface of the lesion or fouling materials by using disinfected toothpicks and the smears were observed microscopically to examine Entamoeba gingivalis infection.

• 用消毒牙签取调查者口腔齿垢物或病灶表面附着物进行涂片，镜检齿龈内阿米巴感染情况。分析口腔健康状况、生活饮食习惯等与齿龈内阿米巴感染的关系。