“…Klock and Krasse were the first to suggest a quantitative study of S. mutans in saliva, discovering that the number of these microorganisms in dental bacterial plaque is strongly linked to their salivary concentration (8). Knowing both S. mutans and Lactobacillus counts improves the accuracy of the microbiological evaluation, as an elevated salivary level of S. mutans is not a reliable indicator of caries risk (9,10).…”