Effects of orally-administered caffeine on the growth of tooth germs in protein-energy malnourished newborn rats.

Lactating dams with 8 suckling pups were fed either a 6 or 20 per cent protein diet from the birth of the pups to day 15. Pups were divided into caffeine and non-caffeine groups and, every other day between days 3 and 13, were either intubated with caffeine (1 mg/100 g body wt) dissolved in 0.1 ml physiological saline solution, or 0.1 ml saline solution as a control. At day 15, the weight of incisors and molar germs, hydroxyproline content, collagen synthesis and calcium contents were determined. Nutritional factors exercised consistent effects on all the parameters, but effects attributable to caffeine intubation were minor. There was lower molar weight in the 20 per cent protein group with caffeine, and collagen synthesis of incisor and molar germs in the caffeine and non-caffeine animals in the 6 and 20 per cent group were different. These parameters showed a significant interaction between nutrition and caffeine. Thus the direct administration of a small amount of caffeine to newborns causes only slight effects on tooth-germ development under some nutritional conditions.