LACTOBACILLI AND DENTAL CARIES IN THE HAMSTER

¹ University of Minnesota, School of Dentistry, Minneapolis, Minn.

1. No correlation was found to exist between caries experience and lactobacillus counts of adult hamsters maintained on three different diets. A significant degree of association was found between the lactobacillus counts and coliform counts; therefore, it appears that intestinal lactobacilli introduced into the mouth of the hamster via the feces may affect the true lactobacillus count.

2. A limited number of offspring of the females used in this experiment experienced the prenatal influence of the previously described diets until 21 days of age and then were fed a high sugar diet for 100 days. A high degree of correlation was obtained between the occlusal scores and lactobacillus counts taken one month prior to sacrifice, but not between the occlusal scores and lactobacillus counts taken at the time of sacrifice. Because of the demonstrated factor of contamination by fecal lactobacilli, the significance of these lactobacillus counts is questionable.

3. A micro method for the determination of lactobacilli and other organisms in hamster saliva is presented, as well as a simplified method of scoring hamster caries.