The Predominant Cultivable Flora of Carious Plaque and Carious Dentine

The quantitative recovery of bacteria from single localized sites, namely the interproximal plaque over a carious lesion and the underlying carious dentine, was undertaken. The samples were collected with minimal oxygen exposure and after dispersion and serial dilution were plated on mitis salivarius agar and various formulations of MM10 agar (a dilute trypticase, yeast extract medium). Higher total counts, Strep, mutans and Strep, sanguis counts were obtained on MM10 supplemented with 5% sucrose. Strep, mutans accounted for 3% of the plaque isolates and 24% of the dentinal isolates. Lactobacillus casei was a prominent organism averaging about 21% of the dentinal isolates.