DENTO-ALVEOLAR RESORPTION IN PERIODONTAL DISORDERS 301 



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Fig. 1. A, marginal, B, basal part of the same septum. On the left side of 

 the septum a vertical resorption has occurred. Through the whole length of the 

 septum (A and B) there are circulatory disturbances and fibrosis of the bone 

 marrow. Only some pieces of the horizontal bone trabeculae are left. In some 

 places circulatory disturbances and loose connective tissue extend from the bone 

 marrow into the pericementum (arrows). These changes are remote effects of 

 the gingivitis. (X 15.) 



their branches into the pericementum of the adjacent teeth, result- 

 ing in a breakdown of pericemental fibers (Fig. 1). All these ob- 

 servations support the assumption that alveolar bone resorption is 

 caused by circulatory disturbances. 



In two types of periodontal disorder, however, there seems to be 

 no relation between gingival inflammation and loss of alveolar bone. 

 Tn some patients a chronic gingivitis is not accompanied by break- 



