Abstract
The synthetic steroid contraceptives, norethynodrel and mestranol, were injected subcutaneously beginning at weanling or pubertal age, into female rats. With increased doses of steroid(s), the caries incidence proportionally increased and with increased frequency of administration and duration of treatment, the total cariogenic dose of the steroid(s) decreased by 95%. A synergistic, or at least an additive, cariogenic effect existed between the two steroids. Absolute and relative salivary glandular weights decreased and increased, respectively, on administration of the steroid. Both the diameter of and relative number of submandibular granular tubules decreased as compared with those of the controls.