Effect of subperiosteally implanted polytetrafluoroethylene (PTFE) material on alveolar bone in the rat.

The aim of this study was to examine the effect on osteocytes after subperiosteal implantation of polytetrafluoroethylene (PTFE) material in the rat maxilla. In four young conventional albino rats, mucoperiosteal flaps were elevated by sulcular incision, and segments (1 x 4 mm) of PTFE material were implanted between bone and flap tissue. After a healing period of 14 days, specimens containing implants and adjacent bone were processed for transmission electron microscopy. The specimens were stepwise reduced to obtain a total of 16 levels for thin sectioning. Osteocytes (n = 640) in alveolar bone underlying implanted material (region 1) and adjacent bone (region 2) were studied to determine the ratio of intact to degenerated cells. In alveolar bone covered by implanted material (region 1) and adjacent bone (region 2), 56% and 16% of the osteocytes, respectively, showed distinct signs of necrocytosis. This study has shown that subperiosteal placement of PTFE material results in partial necrosis of superficial alveolar bone.