The classification of some oral streptococci of human or rat origin

An Adansonian classification of streptococci, many of which were oral in origin, was undertaken. The streptococci tested included both known cariogenic-, or non-cariogenic, strains and new oral isolates. Computation of the data was achieved by two techniques, (i) a comparison of overall similarity values, (ii) detection of nonrandom distribution of attributes. It appears that the oral streptococcal flora includes the well-defined species Strep. mutans, and the considerably more heterogeneous Strep. mitis, Strep. salivarius and Strep. sanguis, with considerable overlap between the last three species. The viridans group were quite distinct from the enterococci but less well separated from the “pyogenic” group of streptococci.