Effect of fluoride on collagen synthesis in the rat

Thirty-six young rats were used to determine the effect of the fluoride on collagen synthesis in healing of fracture. Eighteen rats received 100 ppm fluoride per day, the other 18 were not given fluoride and were used as controls. Then the tibiae of the 36 rats were successively fractured and the animals killed. That is, the first 14 animals of either group were killed one a day, and then the remaining four animals were killed on days 21, 28, 35, and 45 as the tibiae were fractured. Collagen synthesis of the callus was examined histochemically and histologically. In the fluoride-treated group, collagen synthesis was found to be defective, while it was normal in the controls.