Dental Development in Protein-Deprived Infant Rhesus Monkeys

This research investigated the effects of protein-deprivation on tooth development in rhesus monkeys (Macaca muktta). Seventy-three newborn monkeys were fed protein-adequate (n = 44) or protein-restricted (n = 29) diets for the first 120 days of life. Cranial x-rays were taken periodically. Crown-root lengths of deciduous canines, first and second deciduous molars, and first permanent molars were measured on the radiographs. Sample differences were compared using linear regression statistics to determine whether protein restriction delayed the rate of tooth development. Consideration was also given to possible differences in crown size. Buccolingual and mesiodistal dimensions of maxillary and mandibular permanent first molars were measured on dental casts of 29 animals. Experimentally induced protein restriction had only limited effect on tooth size and rate of development. At 120 days, crown-root lengths of deciduous second molars were less than those of controls. This pattern was not observed in the deciduous canine, first molar, or permanent first molar. Crown size of first permanent molars was not measurably affected by temporary restriction of protein.