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The development of the finite element method (FEM) combined block polynomial interpolation with the concepts of finite difference formats and the variation principle. Because of this combination, the FEM overcomes the shortcomings of traditional variation methods while maintaining the benefits of current variation methods and the flexibility of the finite difference method. As a result, the FEM is an advancement above the traditional variation methods. The purpose of this study is to experimentally highlight the thermal behavior of two stomatognathic systems, one a control and the other presenting orthodontic treatment by means of a fixed metallic orthodontic appliance, both being subjected to several thermal regimes. In order to sustain this experimental research, we examined the case of a female subject, who was diagnosed with Angle class I malocclusion. The patient underwent a bimaxillary CBCT investigation before initiating the orthodontic treatment. A three-dimensional model with fully closed surfaces was obtained by using the InVesalius and Geomagic programs. Like the tissues examined in the patient, bracket and tube-type elements as well as orthodontic wires can be included to the virtual models. Once it is finished and geometrically accurate, the model is exported to an FEM-using program, such as Ansys Workbench. The intention was to study the behavior of two stomatognathic systems (with and without a fixed metallic orthodontic appliance) subjected to very hot food (70 °C) and very cold food (−18 °C). From the analysis of the obtained data, it was concluded that, following the simulations carried out in the presence of the fixed metallic orthodontic appliance, significantly higher temperatures were generated in the dental pulp. [ABSTRACT FROM AUTHOR]

CBCT (cone beam computed tomography) is an imaging investigation that provides three-dimensional (3D) images of craniofacial structures. The purpose of this study is to determine the mechanical behavior of an orthodontic system where the lingual treatment technique was used in a 25-year-old female patient from whom a set of CBCT scans was used. CBCT images were processed through software programs such as Invesalius, Geomagic, and Solid Works, to create models containing virtual solids. These models were then imported into Ansys Workbench 2019 R3 (a finite element method software program) for successive simulations to generate displacement maps, deformations, stress distributions, and diagrams. We observed that in the lingual technique, the lowest force occurring on the maxillary teeth is at 1.1, while the highest force appears at 2.3. In the mandible, the lowest force occurs at 4.6, and the highest force at 3.1. The values of the forces and the results of the finite element method can represent a basis for the innovation of new orthodontic springs and also of bracket elements. Thus, by using new technologies, orthodontic practice can be significantly improved for the benefit of patients. Other virtual methods and techniques can be used in future studies, including the application of virtual reality for orthodontic diagnosis. [ABSTRACT FROM AUTHOR]

The paper presents the reverse engineering process for a chain sprocket using 3D scanning technology. First, a detailed 3D scan using an Artec Space Spider 3D scanner is made in order to generate the digital model. Subsequently, based on this model, the 3D modelling process is performed using specialized modelling software such as Artec Studio, Geomagic Design X, and Autodesk Inventor to recreate the geometry and features of the part. A 3D printing technology based on an Ultimaker S5 Pro printer is used to obtain a physical prototype of the part. This technology provides a practical and efficient solution in the reconstruction process of complex objects. The reverse engineering method is useful in different areas such as engineering, manufacturing and repairs, facilitating the reproduction or complete of missing essentials components. [ABSTRACT FROM AUTHOR]

The Proposition 4 from the 11-th volume (called Book of Lemmas) of „Great Books of the Western World" (printed in USA in 1952) presents the properties of a remarkable curve from Antiquity. This curve was studied by Archimedes, who called it Arbelos and it looks like a shoemaker's knife. It consists of 3 semicircles. The first part of the paper is dedicated to the description of an original mechanism, conceived to plot the above-mentioned curve. It is made of a rotating driving element and two dyads of RRR type. The curve plotted by the mechanism checks the equality of areas described by Archimedes. He proved (by using geometric reasonings) that the area of a circle whose diameter is equal to the height of the right triangle inscribed in the Arbelos curve's big semicircle is equal to the Arbelos curve's area. In the second part of the paper, the authors modified the mechanism's parameters and obtained 3 particular cases of Arbelos curves. These particular curves, plotted with the modified mechanism, are also composed of 3 semicircles whilst exhibiting other equalities between areas. The authors used geometric reasonings to prove the equality between the area of each particular curve and the area of a circle whose diameter is equal to the leg of a right triangle inscribed in the big semicircle of the studied particular curve. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Introduction. The objective of this study was to obtain a virtual biomechanical three dimensional model of the human eye though a multidisciplinary collaboration between researchers in various medical and informational fields in order to reach a better understanding of the optical performance of the healthy and diseased eye. Material and Method. In order to obtain the virtual model, we analyzed the CT and MRI images of six patients, aged between 21 and 80 years old, dating from February 2013 until January 2019. These scans totalized 4226 images. We selected to use for the construction of the model the CT images of a male patient of 54 years old. In Vesalius and Geomagic for SolidWorks programs were used. Results. Based on the CT images analysis and using the above mentioned programs, we created a virtual model of the human skull in which the orbit is located, including the eye globe and the extraocular muscles. The SolidWorks virtual model allows the attachment of materials with real properties of the eye tissues. This model can be used in various simulations for the healthy and diseased eye. Conclusions. The biomechanical eye model of the eye was created based on a "in vivo" eye model. As the SolidWorks format enables using materials with identical properties to those of the human eyeball, this virtual model can provide very realistic eye simulations. [ABSTRACT FROM AUTHOR]