DENTO-ALVEOLAR RESORPTION IX PERIODONTAL DISORDERS 



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Fic o. The iiiaigiiial part of a periodontium from a 19-vear-o!d individual. 

 Inflammatory changes are seen in the gingiva. The epithehal attachment is 

 located at the enamel-cementum junction. On the top of the septum osteoid 

 has been laid down. In the three marginal round bone marrow spaces bone 

 resorption and apposition are taking place, as seen in Fig. 4. In the other bone 

 marrow spaces there is apposition in spite of the circulatory disturbances and 

 the fibrosis. ( X 30. ) 



Resorption on one side of a bone trabecula and apposition on the 

 other side is also frequenth' seen. 



In these patients the destruction of aheohir bone is compensated 

 or exceeded by alveolar bone formation owing to hereditary factors 

 and to functional impulses. The same bone production is also re- 

 sponsible for the very quick repair of ah'eolar bone in children after 

 orthodontic treatment. 



In young adults with gingivitis and no loss of alveolar bone, the 

 bone formation incited b\' functional impulses is able to replace the 

 resorbed alveolar bone. This response is seldom seen in adults in 

 our populations. Among east Greenland Eskimos subsisting as hunt- 

 ers far from the white population, it is, however, common to find 



