The effect on bone repair of aspirin cones placed in extraction sockets in dogs: a histopathologic study.

Four canines of eight 2-year-old dogs were extracted surgically, a mucoperiosteal flap being raised. A standardized pair of the post-extraction cavities were filled with three aspirin cones, the other pair being used as controls. The flaps were sutured with surgical gut. The dogs were killed at intervals of 2, 4, 6 and 8 weeks; bone blocks including the cavities were resected and decalcified for histologic examination; serial sections were stained with hematoxylin and eosisin. Microscopic observation on 2 week samples showed an inflammatory response with granulation tissue in both experimental and control cavities with delayed bone apposition in cavities filled with aspirin cones. The 4, 6 and 8 week samples did not show any major difference between the experimental and control cavities. We observed a decrease in infiltrating of cells followed in both by a similarly increasing amount of fibrous tissue and bone remodeling. These results were due perhaps to the details of the experimental method as the suture allowed aspirin to stay in the cavities for only a short time (2--3 days), as occurs in clinical practice.