Effect of Tetracycline on the Transmission of Dental Caries in Rats

¹ National Institute of Dental Research, National Institutes of Health, Bethesda, Maryland

The addition of 0.25 per cent tetracycline to the drinking water has been associated with a reduction of caries activity in young weanling rats on a caries-test diet when separately housed and administered (1) to the mothers during gestation and the first 14 days of lactation, (2) to mothers and offspring the last 7 days prior to weaning, or (3) to offspring the first week postweaning. Tetracycline-treated rats housed with untreated control animals during the caries-test period developed caries of the enamel comparable to controls. These findings give further evidence of the transmissible nature of a "cariogenic flora" in the rat and suggest that tetracycline may be used to depress the oral flora in the study of superimposed factors on experimental caries.