DENTO-ALVEOLAR RESORPTION IN PERIODONTAL DISORDERS 



311 



thickening of the periodontal vessels (Figs. 5 and 10). These and 

 Other alterations facilitating the initiation of periodontal circulatory 

 disturbances may be due to systemic disorders. 



A very quick change in the physiological periodontal conditions 

 followed by loss of alveolar bone occurs frequentlv after irradiation 

 treatment of tumors in the jaws (Stafne and Bowing, 1947; Bruce 

 and Stafne, 1950; Shapiro et ah, 1960). Gingival inflammations and 



Fig. 10. Circulatory disturbances and fibrosis in a bone marrow space in an 

 alveolar septum of the jaw. A large and a small artery seen in the picture both 

 have a narrow lumen due to thickening of their walls. ( X 250. ) 



advanced destruction of the periodontal bone happen so often in 

 these cases that extraction of the teeth in the region which is to be 

 exposed to irradiation is recommended by many radiologists. 



Systemic disorders aftect the resorption and formation of alveolar 

 bone in many ways. They can reduce the periodontium's resistance 

 against irritants and thus contribute to the development of gingival 

 inflammations. It is well known that hormonal disturbances, nutri- 

 tional deficiencies, leukemia, and manv other diseases and old age 

 can have this effect (Sheridan, 1959; Brinch, 1937; Boyle et al., 

 1937; Boyle, 1938; Glickman, 1946, 1948fl, 1948??; Dreizen, 1956; 



