… To meet the exacting requirements as fully as possible, it was necessary to use subjects already living under conditions of limited regimentation. The most appropriate group for our purpose was that to be found in one of our state schools for the mentally retarded. Out of a population of about 2,000 persons of all ages, we found 250 boys and girls between the ages of 13 and 20 years.

This age group seemed best for study because it avoided the consideration of deciduous teeth. We would have preferred greater uniformity of age, but we needed more subjects than could be provided with a narrower age range. Not many more than 200 proved to have capacities for adequate cooperation in our study. The experimental subjects were chosen from the girls; the remaining girls and the boys served as separate control groups. This report will be limited primarily to consideration of the experimental and control groups of girl subjects (Table 1).

… Within specific limitations of investigation, we have been unable to demonstrate differences in the caries advance rates among adolescent children when the ingestion of refined sugar was arbitrarily prohibited or was given daily in large amounts. However we wish to draw attention to these limits of our observations, and request that no inferences be drawn which lie beyond the conditions of our study. These conditions are as follows:

a. The study dealt with altered intake of refined sugar and its products only; during both periods of diet control our subjects received liberal amounts of the sugars which are native constituents of vegetables and fruits.

b. During the period of high sugar ingestion, the sugar was given only with meals, and usually as a constituent of prepared foods.

c. The girls receiving the diets of altered sugar content were under a regimen which was designed to provide a complete diet, both quantitatively and qualitatively. The caloric allowance was constant during the periods of contrasted sucrose intake.

d. Lactobacillus counts proved to offer no reliable index of the likelihood or the rates of caries progression among our subjects, either among those under diet regimentation or· among the members of the control groups.