Abstract
The purpose of this study was to investigate the effect of insulin therapy on bone reactions after placement of titanium screw implants into the tibias of streptozotocininduced diabetic rats. Twelve-week-old male Wistar rats were divided into 3 groups of 12 animals each. The first group (Control) was injected with citrate buffer only; the second group (DM) was induced with a single intraperitoneal injection of streptozotocin, and the third group (Insulin) was insulin-controlled diabetic rats. Tianium screw implants were placed in the proximal metaphyses of the tibias 21 days after the injection. The animals were sacrificed 14 and 56 days after implantation. Undecalcified sections were prepared and evaluated under light microscopy. Histomorphometric measurements were obtained with a computer-based image analyzer, to magnify the unit bone mass around the implant and the rate of implant-bone contact. The DM group significantly reduced implant-bone contact and bone volume around the implants. However, in the Insulin group, only slight differences in both bone contact and bone volume were noted when compared with the Control group. These results suggested that insulin therapy prevented a decrease of implant-bone contact and bone volume around the implants in the tibial metaphyses of streptozotocin-induced diabetic rats. Therefore, insulin therapy is useful to prevent reduction of bone attributable to surrounding dental implant that may occur with diabetes mellitus patients.
