| Dental implants provide predictable results and unique restorative opportunities to patients. However, treatment may take many months, and some diseases or anatomical situations may prevent implant placement. For these reasons, researchers strive to improve healing and bone growth around implants. Various growth factors and other biomimetic substances have been used toward this goal. Because of increasing research in this field, demand for methods which quantify bone growth has also increased.;This dissertation examines the effects of fibroblast growth factor, FGF-1, on the healing of implants in rat tibiae. A radioimaging technique utilizing Tc-99m-MDP was used to evaluate these effects. Finally, healing in a diabetic rat model was studied.;Implants were placed in the proximal tibia of 48 rats in three groups---control, FGF, and diabetic. The control group received implants only, while the FGF group received 65 mug of FGF-1 administered in an activated fibrin matrix. Diabetics were injected with 65 mg/kg of streptozotocin prior to surgery, and received implants only. After 5 days, subsets from each group were imaged after injection of Tc-99m-MDP, a radiopharmaceutical which is associated with bone activity. After healing 14 days, all implants were retrieved, embedded in plastic, and analyzed histomorphmetrically. Results were analyzed statistically using MANOVA and Fisher's PLSD test.;Histomorphometric analysis revealed a significant increase in osteointegration and bone volume associated with implants treated with FGF-1. A significant increase in Tc-99m-MDP activity was also demonstrated around implants treated with FGF-1. Diabetic animals showed significantly less osteointegration than controls, but associated bone volume was 4 times greater than controls. Diabetic animals also demonstrated an increase in localized Tc density compared to controls.;These experiments show that manipulation of the host-implant interface can be achieved with the addition of growth factors, that diabetes impacts implant healing, and that radioimaging with Tc-99m-MDP can identify differences in bone activity early in the healing process. |
