THE ORAL BACTERIAL FLORA AS RELATED TO DENTAL CARIES IN THE SYRIAN HAMSTER

¹ Walter G. Zoller Memorial Dental Clinic and the Department of Bacteriology and Parasitology, University of Chicago, Chicago, Ill.

The oral bacterial flora of the Syrian hamster was investigated. Specimens were obtained from the molar tooth surfaces by means of a small aspirating tube. The specimens were grown on a differential medium having pH of 5.0.

Colonies on a total of 227 acid agar plates, inoculated with the perimolar specimens from 179 hamsters which had been maintained on various diets, were observed and studied. Eight kinds of aciduric microorganisms were isolated: staphylococci, streptococci, and unidentified pleomorphic organisms and 5 varieties of lactobacilli.

Comparison of caries indices with the numbers of microorganisms isolated indicated some degree of association of lactobacilli and streptococci with the development of carious lesions. There was no clear evidence of a direct relation between the number of microorganisms isolated and the vitamin content of the various diets.