DIETARY CASEIN-SUCROSE RATIOS AND THEIR EFFECTS ON MINERALIZED TISSUES

¹ National Naval Medical Research Institute, Naval Dental School, Bethesda, Md., and Georgetown University Schools of Medicine and Dentistry, Washington, D. C.

Rats were maintained for 6 weeks on diets containing 20, 30, and 40 per cent casein, control animals fed a standard lab chow were run at the same time. Maximum body weight gain was obtained on the 30 per cent casein diet. The femurs and upper and lower pairs of incisors were removed, weighed, and analyzed for nitrogen, calcium, and phosphorus. The proteins of the femurs and incisors were isolated and their amino acid composition determined.

Femur weight and calcium content were greatest on the 40 per cent casein diet, there was no change in phosphorus content, the nitrogen content increased slightly with increased dietary protein. Several of the amino acids in the isolated protein also appeared to be increased.

Incisor weight increased slightly with increased dietary protein. Calcium and phosphorus decreased slightly. Nitrogen content of the incisors increased slightly. Analysis of the isolated proteins showed a tendency toward an increase in amino acid content of several amino acids.

All of the rats on all the diets developed carious lesions. None of the animals developed any Score III or severe caries. There were no marked differences in the caries response in any of the 3 casein diets. The control diets gave higher incidence of caries of a more severe nature than did any of the casein diets.