microradiography of boxe rp:sorptiox 467 



Conclusion 



The results have demonstrated some of the facts that can be 

 learned from microradiographic studies of bone and have shown 

 the importance of resorption in both the normal and the abnormal 

 skeleton. The quantitation provides some sort of base line for com- 

 parison and makes possible the constructive evaluation of therapv 

 in bone disorders. 



SrMMARY 



Bone turnover was measured in a defined area bv techniques in- 

 volving semiquantitati\'e analvsis of microradiographs. Formation 

 and resorption of bone as well as its porosity were measured and 

 related to the age of the individual, and comparisons were made be- 

 tween normal and abnormal tissue. 



It was apparent that in normal individuals an increase in the 

 amount of bone resorption is what produces the porosity character- 

 istic of aging bone. Osteoporotic bone appeared to be an exaggera- 

 tion of the normal aging process in that the increased resorption 

 caused the porosity. 



Bone from individuals with Paget's disease, hyperparathyroidism, 

 osteogenesis imperfecta, and rickets had a distinctive appearance. 



Acknowledgments. I should like to thank Dr. Gershon-Cohen for his 

 support and William Lafferty for his excellent technical assistance. 



References 



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