The infectious and transmissible nature of experimental dental caries: Findings and implications

In both hamsters and Osborne-Mendel rats dental caries appears to be an infectious and transmissible disease which involves a penicillin-sensitive flora. The findings reported suggest that if this flora is present or is inoculated into young animals, rampant caries can be induced by a high-carbohydrate low-fat diet within 35 days. When low to negligible caries has been found in animals similarly fed, the flora presumably has not been present in sufficient quantity to be pathogenic. Caries activity was markedly reduced in hamsters and rats after the penicillin-sensitive flora had been depressed prior to feeding the test diet. Hamsters whose flora had been depressed, in some cases, produced several generations of progeny with negligible activity. Marked differences in activity apparently result from alterations or variables in the flora which animals acquire, transmit, and develop during the course of an experiment. Thus, a number of interpretations, which have been made to explain differences in caries activity observed in past studies, must be reconsidered in terms of variations possibly induced in the microbic flora.