调查上海市区不同人群的口腔原虫的感染情况。从齿垢物取标本作新鲜涂片法检查。在４５０人中齿龈内阿米巴和口腔毛滴虫的感染率分别为２１．７８％和１．１１％。口腔科门诊患者的齿龈内阿米巴的感染率高达２８．３７％，而正常人的感染率仅为１０．７１％，两组差异非常显著。提示这两种原虫的感染与年龄有关，其感染率随年龄的增长有上升趋势，以及两种原虫感染与口腔疾病关系密切。 Investigation of oral protozoan infections in different populations in Shanghai. Take specimens from tartar for fresh smear test. In 450 people, the prevalences of Entamoeba gmea and Trichomonas vaginalis were 21.78% and 1.11% respectively. The infection rate of dental gingivalis in the dental clinic was as high as 28.37%, while the infection rate in normal people was only 10.71%. The difference between the two groups was very significant. It is suggested that the infection of these two protozoa is related to age. The infection rate increases with age, and the infection of the two protozoa is closely related to oral diseases.