Background: Absorbable membranes and screws are useful tools to reconstruct alveolar ridge in the guided tissue regeneration since it eliminates the reentry surgery. Objective: Our goal was to evaluate histologically the biocompatibility of a screw produced with fully processed bovine bone. Methods: Cortical bovine bones were obtained in a local slaughterhouse, mechanically and chemically cleaned without demineralization or high temperature. Screws (1 x 3 mm) were made in a lathe and sterilized by gamma radiation. Bone defects were created in the femur of twenty male rats (Rattus norvegicus) and filled with one screw. After 10, 14, 30 and 60 days the rats were killed and the femurs fixed in 10% buffered formalin. Histological processing was conducted and 6 µm tick sections were stained with haematoxylin and eosin. Results: All animals demonstrated no signs of suppuration, edema or infection throughout the study period. Occasional findings of neutrophil polymorphonuclear leukocytes were observed just during the initial period. In the others periodos inflammatory reaction was minimal, not observing plasma cells and lymphocytes. The specimens presented formation of a very thin capsule soon 10 days that remained during all experimental periods. The resorption of the material started after 14 days becoming more intense after 60 days, mainly at the medullar space. The absorbed material was replaced by new bone and fibrous tissue. Conclusions: On the basis of these results, it can be concluded that processed bovine bone screws implanted in the bone defects of rats is absorbable and biocompatible. Support: FAPESP, CNPq, PIBIC/CNPq, PRP-USP, BAUMER S.A.

Back to the Periodontal Research - Therapy Program
Back to the 81st General Session of the International Association for Dental Research (June 25-28, 2003)

Top Level Search