VI. EFFECTS OF DEFICIENCY 247 



of the shaft into the transparent cartilage, are seen. In early rickets the 

 individual threads are short, thin, and hard to see; in moderate and ad- 

 vanced cases the threads are long and coarse. In the shaft, the cortex may 

 appear thickened and composed of longitudinal, slightlj^ curved interlacing 

 lamellae. The bone shadow may be slightly or moderately diminished. In 

 the severe forms, there is marked translucency of the entire shaft. If present, 



Fig. 23. Cartilage mass which has been compressed projecting into metaphysis. 

 Predominant!}' connective tissue marrow. 



the x-ray will always show these distortions and fractures as described, 

 especially after healing has begun. 



Whether or not the condition of the teeth is influenced by the lack of 

 vitamin D is still an open question. It seems that primary dentition may 

 be delayed in rickets, and when the teeth do appear they may do so in an 

 abnormal order. The permanent teeth also show defects attributable to 

 I'ickets.'^^' " The teeth which are developing at the time when the rickets 

 is most active may, when they erupt, show a hypoi)lasia of the enamel. 



'^ M. M. Eliot, S. P. Soutluior, }i. A. Anderson, andS. Arnini, Am. ./. Diseases Chil- 

 dren 46, 458 (193.3). 

 " A. F. Hess and H. Ahramson, Dental Cosmos 73, 849 (1931). 



