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This work focus on the development of a new sensor for residual stress measurement using fiber optic Bragg sensors. A known stress field was induced on a specimen and results obtained from both the fiber optic Bragg sensors rosette and traditional electrical strain rosette were compared. Also a FEM model was used to confirm the obtained results.

A evolução tecnológica das últimas décadas, dos sistemas de levantamento de forma, das preparações dentárias, do software de desenho virtual (0W), dos materiais dentários e máquinas de fresagem (CAM), levou ao desenvolvimento de vários sistemas CAD-CAM com aplicabilidade em Medicina Dentária (ex. Everestt Kavo, disponível na FMDUPJ). Nesse sentido o Grupo da Prótese Dentária e Oclusão da FMDUP desenvolveu uma colaboração interdisciplinar com o Laboratório de óptica e Mecânica Experimental (LOME) da FEUP no sentido de adoptar as tecnologias normalmente aplicadas em Engenharia para optimização de estruturas utilizadas em Próteses Dentárias. Foi então concebida uma metodologia de exportação dos ficheiros de desenho virtual para integração com os métodos de análise de tensões numéricos e experimentais, permitindo desta forma o estudo de situações compatíveis com a realidade clínica. Neste trabalho é apresentada uma aplicação desta metodologia em diversos trabalhos experimentais de análise de tensões em próteses parciais fixas dentárias.

Partially encased beam is a steel-concrete composite structure, made-up with a hot rolled profile and filled with concrete between flanges. Such structural element improves load-bearing capacity at elevated temperatures. Metal ceramic Fixed Partial Dentures (FPD) are suitable to increase fracture resistance presenting higher clinical longevity. This type of prosthesis is mainly used when a great number of teeth replacements are needed. The FPD under analysis is defined by a metallic infrastructure (titanium) and by a ceramic coating. The advantages of hybrid FPI) lie in their predictable biomechanical behavior versatility and cost. The main disadvantage is related to aesthetic functionality. Karlsson (1986), Lindquist & Karlsson (1998) and Palmqvist (1993) quantified the life time for hybrid FPD, referring lO years in service lo be a survival of break point. The connector design is of great importance to improve smooth stress pattern in the region between teeth. This region is also restrained by biological and aesthetic reasons, Ceramic material presents elevated failure rate in FPD due to brittleness. This work intends to predict fracture resistance to different loading conditions, using a smeared fracture approach (continuous damage mechanics), Results agree well with experimental evidence.

This paper presents an attempt to obtain the displacement field produced in a human mandible during the mastication. This information is of crucial importance in the stress estimation. Rubber bands fixed on mandible bone are used to simulate muscles and tendons being the load applied at the incisive teeth and controlled by a load cell. The temporomandibular joint and ligaments are implemented through the fixation of the mandible to a mechanic rig. The global boundary conditions were defined according to the anatomic model. The in-plane ESPI (Electronic Speckle Pattern interferometry) technique [1] is used for the measurement of flue global displacement field at mandible surface. The numerical simulation of the 3D modal mandible [2], which includes the cortical and spongeous bone, is performed using a commercial finite element method code, Ansys® [3J. The figure 1 shows the experimental results with ESPI and the numerical simulation.