الفهرس 
صفحة العنوانOnly 14 pages are availabe for public view
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Abstract
Since dental implants were introduced for rehabilitation of the completely edentulous patients in the late 1960s an awareness and subsequent demand for this form of therapy has increased. The use of implants have revolutionized dental treatment modalities and provided excellent long-term results.
In evaluation of the long-term success of a dental implant, the reliability and the stability of the implant–abutment and implant bone interface plays a great role. In general, the success of the treatment depends on many factors affecting the bone-implant, implant-abutment and abutment-prosthesis interfaces.
Analyzing force transfer at the bone–implant interface is an essential step in the overall analysis of loading, which determines the success or failure of an implant. It has long been recognized that both implant and bone should be stressed within a certain range for physiologic homeostasis. Overload can cause bone resorption or fatigue failure of the implant, whereas underloading of the bone may lead to disuse atrophy and subsequent bone loss. Prosthetic components are subjected to a complex pattern of horizontal and vertical force combinations. Yet all force components do not have the same impact with respect to material resistance and incidence of failure. Force vectors that are directed along the main axis of the implant are compressive in nature and remain well below the material‘s resistance in compression.
A key factor for the success or failure of a dental implant is the manner in which stresses are transferred to the surrounding bone. The Finite Element Method (FEM) allows researchers to predict stress distribution in the contact area of implants with both of cortical and cancellous bones. Three-dimensional (3D) FEM has been widely used for the quantitative evaluation of stresses on the implant and its surrounding bone.