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The success of endodontic treatment is dependent on the removal of bacteria. A modern strategy to reduce bacterial load is laser irradiation. During this procedure, there is a local increase in temperature with possible side effects. The aim of this study was to determine the thermal behavior of a maxillary first molar when performing the conventional irradiation technique using a diode laser. For this study, a 3D virtual model of a maxillary first molar was created. The preparation of the access cavity, the rotary instrumentation of the palatal root canal and the laser irradiation protocol were simulated. The model was exported in a finite element analysis program where the temperature and heat flux were studied. Temperature and heat flux maps were obtained, and the temperature increase on the internal wall of the root canal was analyzed. The maximum temperature value exceeded 400 °C and was maintained for less than 0.5 s. The obtained temperature maps support the bactericidal effect of diode laser and the limitation of damage to surrounding tissues. On internal root walls, the temperature reached several hundred degrees Celsius, but for very short durations. Conventional laser irradiation is an adjuvant method of decontamination of the endodontic system.
RESUMO
(1) Introduction: The changes in the joint morphology inevitably lead to prosthesis, but the hip pathology is complex. The hip arthroplasty is a therapeutic solution and can be caused, most frequently, by primary and secondary coxarthrosis due to or followed by traumatic conditions. The main aim of this study was to find the method of revision hip prosthesis that preserves as much bone material as possible and has sufficiently good mechanical strength. (2) Materials and Methods: In this study, in a first step, the two revision prostheses were performed on bone components taken from an animal (cow), and then, they were tested on a mechanical testing machine until the prostheses physically failed, and the force causing their failure was determined. (3) Results: These prostheses were then modelled in a virtual environment and tested using the finite element method (FEM) in order to determine their behaviour under loading from normal human gait. Displacement, strain, and stress maps were obtained. (4) Discussion: Discussions on hip revision prostheses, method, and theory analysis are presented at the end of the paper. (5) Conclusions: Important conclusions are drawn based on comparative analyses. The main conclusion shows that the both orthopaedic prostheses provide a very good resistance.
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INTRODUCTION: The human knee is one of the most complex human joints, by the number of components, by the stresses to which it is subjected, by the complicated spatial geometry of the components and by the existence of multiple contacts between different components. MATERIAL AND METHOD: A series of modern devices and equipment that were used for the three-dimensional reconstruction of the components of the analyzed systems. RESULTS: Also, the elements of a knee prosthesis were modeled in a parameterized virtual environment and six orthopedic systems were compared. These systems have been studied using the finite element method using loads specific to normal human gait. DISCUSSION: The results obtained consisting of maps of displacements, deformations and stresses were stored, analyzed and compared. CONCLUSIONS: Finally, important conclusions were highlighted.
RESUMO
INTRODUCTION: Prosthesis loosening is an alteration of the function and position of a total hip prosthesis with reference to the initial surgical moment. The main mechanism unanimously accepted for aseptic prosthetic losses at the level of the cup is represented by the biological mechanism. MATERIAL AND METHOD: Experimental and virtual, interdisciplinary tools, techniques and methods were used to determine the behavior of the hip replacement prosthesis with the morcellated graft and the reconstruction net. Performing an orthopedic assembly with a morcellated bone graft and reconstruction net. An assembly was performed on a hip joint taken from an animal (cow). The biological material and the components of the prosthesis were prepared similarly to the revision prosthesis intervention. Experimental testing of orthopedic assembly with morcellated bone graft and reconstruction net. This assembly was tested on a universal machine to determine the maximum force at which it yields. This was 1790 Kgf, i.e. 17559 N. Virtual experimental testing of the hip joint with orthopedic revision assembly with a morcellated bone graft and reconstruction net for normal gait loading. The orthopedic assembly with the morcellated graft and the reconstruction net was reconstructed in the virtual environment. Normal load was used. Results maps were obtained. CONCLUSIONS: Analyzing the results from the two tests, experimental and virtual, and important conclusions were drawn regarding this orthopedic assembly.
