The important lesions of rickets, whether caused by a deficiency of vitamin D or by an extreme deficiency of calcium, are to be seen in the calcified structures of the body. The most highly calcified structures of the body are the teeth. Enamel, according to von Bibra,1 consists of approximately 96.41 per cent inorganic substance and 3.59 per cent organic substance, and dentine, of 72.39 per cent inorganic and 27.61 per cent organic substance. It is to be expected, therefore, that disturbances of calcium metabolism will affect the process of calcification of the teeth.
The association of rickets with defective structure of the teeth has long been recognized clinically, but detailed knowledge of the lesions has awaited the experimental production of these defects. Without doubt the most comprehensive study of rickets and the associated dental lesions has been made by Mellanby.2 In her report were described the effect