The Prevention of Experimental Tooth Decay by Tube-feeding

Abstract
When intact or desalivated caries-susceptible albino rats were fed adequate amounts of a caries-producing diet by stomach tube they did not develop tooth decay. In contrast, all but one of the intact litter mates and all of the desalivated litter mates which consumed the same diet orally had dental caries. The critical ratios of the differences between the control and experimental groups ranged from 5.7 to 26.6, which indicated that the differences were highly significant. Histologic examination showed that the molar teeth of both groups were surrounded by a great abundance of microorganisms. In the controls, the microorganisms were in direct contact with the tooth surfaces; in tube-fed rats they were separated from the enamel surfaces by a thick organic membrane (possibly remnants of Nasmyth's membrane) and by foreign matter which was firmly impacted in the fissures. The results of this experiment suggest that, with all other factors being controlled and equal, tooth decay is prevented in caries-susceptible rats when the direct effects of food in the oral cavity are eliminated.