歯垢形成性 Streptococcus mutans の無菌マウスロ腔内への定着に関する研究

In the previous study, the establishment of a plaque-forming streptococcus strain, Streptococcus mutans PK1 in germfree ICR: JCL mice was investigated and it was recognized that the organisms could be established in the mouth and digestive tract.Further long term investigation was carried out to test for the establishment of the organisms in the oral cavity of germf ree mice at 13 weeks after inoculation and compared with the results of the previous study.The results obtained were as follows:1) The organisms were isolated from all specimens of teeth surfaces and the number of the organisms were in the level of less than 5.2×104 to 9.9×106CFU/g.2) No statistical difference of viable cell number in the oral cavity was recognized between two groups of mice at 4 and 13 weeks after inoculation.