| This thesis represents an experiment designed to investigate the role of biomechanics in the control of tissue remodeling at the interface between implants (orthopaedic and dental) and bone. An animal experiment was conducted in which screw-shaped titanium implants, osseointegrated into radial and mandibular bone sites in dogs, were subjected to a controlled, cyclic load program for several consecutive days. The tissue morphology and biology around the implants was quantitated using a personal computer based system designed for this purpose. The quantitative and qualitative results for loaded implants were compared to results for unloaded control implants.;The quantitative histomorphometric data collected for this thesis contribute to defining terms such as osseointegration, at least as they apply to the implants and implant sites of this thesis.;Using finite element (FE) models, several aspects of biomechanics at the implant-tissue interface were investigated, including: (1) the importance of interface assumptions on model results, and (2) general trends in the stress distribution between threads of the implants. FE models, in which bonding between implant and bone is not assumed, predict different stress magnitudes and distributions than models assuming bonding. The results also demonstrate that relative displacements can occur between implant and tissue in the absence of an implant-tissue bond. These results demonstrate that conclusions based on FE models of bone-implant interfaces are likely to be inaccurate without accurate information concerning the actual biomechanics of the implant-tissue interface.;Consistent differences between experimentally loaded and control implants were not detected. The reasons for a lack of consistent differences may include a variety of factors related to the experimental loading protocol, the nature of the bone-implant interface, and uncontrolled experimental variables. |
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