Osseointegration is defined as the direct physical and practical relation between the living tissue and implant surface. Although, success rate of dental implants is high, implant failure occurs. Overloading implants from occlusal forces are known as one of the main reasons. In order to have successful implant, a dynamic balance must be provided between mechanical and biological elements (Isidor, Flemming 1996). Şimşek et al. reported bone quality, oral sanitation, host medical condition and biomechanical parameters as the main reasons for implants failure. Also, implant fixture micromotion and inappropriate stress in the bone implant interface is known as the potential reasons for early bone loss and implant failure (Şimşek, Barış 2006). Even so, implant position in jawbone, bone density; biomaterial properties of implant surface, treatment technique, loading history and patient clinical status are the influential factors in implant success (Brunski, J.B. 1999). Although there are many studies on stress distribution of implants in bone-implant interface, majority are limited to current implants in the market. However, current designs have been developed by marketing purposes rather than scientific considerations. Therefore, there is need to introduce and analyse new designs in order to optimize implant structure. Recent investigations have shown reliability of FEA method in simulating human jawbone situation. This research aims to develop a new dental implant with better life expectancies and introduce an optimized implant based on FEA stress analyses and experimental tests. Therefore, based on literature recommendations a series of new design factors are defined and analysed. In this study, a primary design is created in AutoCAD and yields to 3 different implants developed in SolidWorks. Branemark MK IV was selected as the bench model to play role of control group. Then, CT-scan images of human jawbone are imported to MIMICS to create a host bone model. Implant and jawbone models are assembled in 3-Matic and exported to Abaqus for final analyses. A series of loadings are defined to examine implant performance in different conditions. Branemark and C-3 implants are manufactured from Titanium for experimental analyses. Mechanical tests on sawbone foam blocks and cadavers are targeted to portray realistic performance. This research demonstrates C-3 model as the optimized dental implant, which presents a new design profile and better performance in low bone densities. The FEA and experimental results validate the benefit of the new design compare to the conventional ones. Furthermore, results can provide a basis for future designers to develop further optimizations.

No / Australopithecus anamensis is the stem species of all later hominins and exhibits the suite of characters traditionally associated with hominins, i.e., bipedal locomotion when on the ground, canine reduction, and thick-enameled teeth. The functional consequences of its thick enamel are, however, unclear. Without appropriate structural reinforcement, these thick-enameled teeth may be prone to failure. This article investigates the mechanical behavior of A. anamensis enamel and represents the first in a series that will attempt to determine the functional adaptations of hominin teeth. First, the microstructural arrangement of enamel prisms in A anamensis teeth was reconstructed using recently developed software and was compared with that of extant hominoids. Second, a finite-element model of a block of enamel containing one cycle of prism deviation was reconstructed for Homo, Pan, Gorilla, and A. anamensis and the behavior of these tissues under compressive stress was determined. Despite similarities in enamel microstructure between A. anamensis and the African great apes, the structural arrangement of prismatic enamel in A. anamensis appears to be more effective in load dissipation under these compressive loads. The findings may imply that this hominin species was well adapted to puncture crushing and are in some respects contrary to expectations based on macromorphology of teeth. Taking together, information obtained from both finite-element analyses and dental macroanatomy leads us to suggest that A. anamensis was probably adapted for habitually consuming a hard-tough diet. However, additional tests are needed to understand the functional adaptations of A. anamensis teeth fully.

The Forestry Department at Mississippi State University has been contracted to design and test a novel beam to be used to create crossing platforms for cranes operating in muddy, swampy areas. To date, they have performed stress analyses on 30 beams, but their physical testing method requires costly amounts of material and man hours. It is theorized that the finite element method may be used as an alternative method of analysis in order to reduce costs. The focus of this study is to create models of tested beams using the finite element solver, ANSYS, and verify the accuracy of these models using the results of the Forestry Department’s physical testing.

O presente trabalho consiste basicamente no desenvolvimento de um programa de engenharia denominado SAJ (sistema de análise de juntas) capaz de realizar uma análise detalhada do comportamento de dois dos diversos tipos de juntas coladas existentes, a junta simples colada (\"single lap joint\") e a junta dupla colada (\"double lap joint\"). Sendo que foram analisadas juntas coladas com aderentes de material compósito ou, então, compostas de aderentes de compósitos e metal. O programa de engenharia desenvolvido possibilita o cálculo das tensões, dos esforços e dos deslocamentos nessas juntas. Para validar o referido programa, os resultados obtidos do mesmo foram confrontados com os resultados obtidos para condições semelhantes utilizando \"softwares\" comerciais de elementos finitos e de cálculo de juntas. Após a validação do programa, são apresentados alguns estudos de fatores que influenciam na resistência da junta colada, verificando a influência do comprimento de \"overlap\" (sobreposição), a rigidez do adesivo e a espessura da camada adesiva. Também é apresentada uma análise de falha dos aderentes de compósito evidenciando assim, as potencialidades e limitações desta ferramenta computacional para a área de desenvolvimento de produto. / This work consists on the development of software called SAJ which can analyze a bonded joint behavior in detail, not only for single lap joint, but also, for double lap joint. These joints could be made of composite/composite materials or metal/composite as adherentes. The software developed can calculate the joints stresses, loads and displacements. The results obtained are compared to the results obtained using commercial software and the same problems proposed. After the validation of SAJ, some studies were performed in order to determine how some characteristics affect the joint stresses distribution as overlap length, adhesive elastic modulus, adhesive thickness and a failure analysis of composite adherents showing the potential and limitation of this computational tool for the product development area.

O presente trabalho consiste basicamente no desenvolvimento de um programa de engenharia denominado SAJ (sistema de análise de juntas) capaz de realizar uma análise detalhada do comportamento de dois dos diversos tipos de juntas coladas existentes, a junta simples colada (\"single lap joint\") e a junta dupla colada (\"double lap joint\"). Sendo que foram analisadas juntas coladas com aderentes de material compósito ou, então, compostas de aderentes de compósitos e metal. O programa de engenharia desenvolvido possibilita o cálculo das tensões, dos esforços e dos deslocamentos nessas juntas. Para validar o referido programa, os resultados obtidos do mesmo foram confrontados com os resultados obtidos para condições semelhantes utilizando \"softwares\" comerciais de elementos finitos e de cálculo de juntas. Após a validação do programa, são apresentados alguns estudos de fatores que influenciam na resistência da junta colada, verificando a influência do comprimento de \"overlap\" (sobreposição), a rigidez do adesivo e a espessura da camada adesiva. Também é apresentada uma análise de falha dos aderentes de compósito evidenciando assim, as potencialidades e limitações desta ferramenta computacional para a área de desenvolvimento de produto. / This work consists on the development of software called SAJ which can analyze a bonded joint behavior in detail, not only for single lap joint, but also, for double lap joint. These joints could be made of composite/composite materials or metal/composite as adherentes. The software developed can calculate the joints stresses, loads and displacements. The results obtained are compared to the results obtained using commercial software and the same problems proposed. After the validation of SAJ, some studies were performed in order to determine how some characteristics affect the joint stresses distribution as overlap length, adhesive elastic modulus, adhesive thickness and a failure analysis of composite adherents showing the potential and limitation of this computational tool for the product development area.