Abstract
Study was planned to investigate the percentage of the appearance of S-, SR- and R-type of Lactobacillus acidophilus and their distribution in the oral cavity of school children.
The results showed that the percentage of the colony count of SR-type, especially that of R-type, was found always higher than that of S-type. But the percentage of S-type was found rather higher in the gargled water harvested from the children suffered from caries. While S-type appeared in a high percentage in the softened dentine of acute caries, it was found very low in the softened dentine of chronic caries.
On the other hand, both R-and SR-type seemed to be found in all conditions examined. S-type colonies, moreover, appeared to prevail in some special environment such as acute caries and further in the deep foci to which oral flora can not invade easily.
When similar studies were made on larger number of children and similar results were obtained, it would be able to find out the difference, if any, in the pathogenicity of Lactobacillus acidophilus in dentine by type as well as the problem of the originality in the type.
