Diabetes mellitus and corticotherapy as risk factors for alendronate-related osteonecrosis of the jaws: a study in Wistar rats.

Background: The purpose of this study was to investigate the influence of diabetes and corticotherapy on the development of osteonecrosis of the jaws associated with sodium alendronate.

Methods: Rats were allocated into 4 groups of 11 animals each, representing different treatments: (1) alendronate; (2) alendronate and corticotherapy; (3) alendronate and diabetes; and (4) control. Tooth extractions were performed in all animals, and histological analysis was performed by hematoxylin and eosin staining and immunohistochemistry using anti-bone morphogenetic protein (BMP)-4 and anti-matrix metalloproteinase (MMP)-13 antibodies.

Results: On hematoxylin and eosin analysis, proportions of inflammatory infiltrate, microbial colonies, and osteonecrosis were significantly greater in the diabetes group. BMP-4 expression in connective tissue was higher in the corticosteroid group than the alendronate group. There were no significant differences between the other groups. MMP-13 expression did not differ between the groups analyzed.

Conclusion: Diabetes but not corticotherapy is associated with jaw osteonecrosis in rats undergoing alendronate therapy and subjected to tooth extractions.