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We report the case of a patient with simultaneously two intrauterine devices with different mechanism of action. By cumulating the effects and adverse reactions of the two intrauterine devices, the patient had severe dysfunctional bleeding and pelvic-abdominal pain. Using scanning electron microscope, we analyzed the surfaces of the two retrieved intrauterine devices in order to establish the physio-pathological mechanisms that occurred and lead to a local but also a hormonal disorder in the reported patient. We would also like to draw the alarm that a complete evaluation (clinical and imagistic) are mandatory prior to the insertion of an intrauterine device.

The paper presents an experimental study on the influence of the polyurea layer on the behaviour of metal plates loaded through air blast while the polyurea coat is placed on the loading face of the plate. To assess the influence of polyurea layer, the permanent maximal deflections of tested plates were used. A strong dependence between the effect of polyurea coating on the permanent deflection and stand-off was found. The analysis based on comparison between theoretical predictive functions and test result have shown that in almost all tested scenarios the bilayered plates results are less promising than the predicted results of monolithic steel plates of equal areal density.

The etiology of the TMJ disorders is a very controversial topic in the orthodontic literature. The symptoms include pain, muscle spasms, clicking and limitations of the mandibular movements. This pathology is also known as myofacial pain dysfunction and it appears to be more common in young female patients. Muscle hyperactivity, occlusal trauma and parafunctional oral habits are often associated with this syndrome. There are several noninvasive ways to treat this type of pathology (medication, removable appliances, TENS therapy) but the most common refers to acrylic splints. Nonpermissive or repositioning acrylic splints, that often include an acrylic bite plane, representthe most popular treatment alternative nowadays. These appliances can set the condyle in a centric relation in order to reduce muscle spasm, pain and the levels of cellular hypoxia.

Von Mises Stress in a finite element analysis method is widely used by designers because it helps them to check whether their design will withstand a given load condition, in other words, if the maximum value of the Von Mises Stress induced in the material is more than the strength of the material or not. In this paper it will be presented the Von Mises Stress analysis of an armchair seat redesigned from an wooden based model, into a polyurethane more compact structure. In order to perform the testing required, a 3D design was made after the wooden model. This model was made so it will be easier to build, more compact, and with a lower weight and maybe having a more resistant structure compared to the wooden design.

The paper presents the experimental research regarding the use in construction field of clay bound earth and wood chips combined with classical binders (cement and lime). New building materials were manufactured (for ground storey houses) by using clay bound and wood chips. The clay bound earth is present all around the Globe. Due to this reason there is one of the most common natural resources of the planet. The wood chips are a waste from wood furniture industry. The paper presents experimental research on mixtures made of clay bound, cement, lime, sawdust and water. Experimental tests were made for: apparent density, bending tensile strengths and compression strengths. The new manufactured building materials have physical and mechanical properties similar to lightweight mortars and bricks. Through clay bound and sawdust reusing a very good impact on environment and life health will be generated. The new building materials studied can be used at non-loadbearing and loadbearing masonry elements. The Batch 4 was the best one, having a bending tensile strength of 3.75 MPa and a compressive strength of 13.41 MPa at 365 days. It has the same mechanical characteristics like bricks made of from burned clay bound. The 25% water percentage is good enough for a satisfactory workability (the material flows to infill the mould); in case of the decrease of the water percentage (especially at 15%), the material has no flow and consequently, is necessary to apply a low pressure (by hand) to infill the mould. A 30% water percentage significantly improves the workability of mixtures.

Mode II testing is performed on a polyurethane foam as a particular case of mixed-mode four-point testing. Crack initiation and propagation in Mode II depends on the geometrical parameters of the testing configuration. Numerical XFEM simulations are done in order to clarify the situations in which the crack doesn’t propagate and failure is produced in the region of supports. A combined experimental-XFEM analysis is recommended to fully understand the particularities of the behaviour of cellular materials.

This study compares, by means of the finite element method (FEM), the behaviour of the restorations done with the same material, the same adhesive system and under the action of the same force values applied to four 3-D lower premolar finite element models, representing four different cavity shapes. An extracted lower premolar which presented an abfraction lesion has been used. The restoration was achieved by using etch–and-rinse adhesive systems and Giomers. The premolar was scanned and the resulting sections were processed and converted into a 3D digital format. Thus, a model of finite elements which presented a restored wedge-shaped cavity in the cervical dental area was obtained. Then, by modifying the shape and dimensions, there were created another 3 modified-shape cavities. Forces of different magnitudes (90-150N), exerted at a 45 degree angle on buccal cusp, have been applied. If adhesive system tensile strength is about 25MPa, this limit is reached at 120N only for the third model. For Beautifil FO2 the tensile strength is not reached when maximum forces are applied (150N) and for Beautifil II, the tensile strength is reached only for model 4, when a force of 150N is applied. In order to increase the retention of the abfraction restoration, changing the shape of the cavity should be associated with the use of Giomers and adhesive system with tensile strength exceeding 25MPa.

Structural and morphological features of compositions based on LDPE which contains different types of fillers for creation of conductive polymer products are presented in this article. Different types of fine metallic fillers, such as Al, Br, Cu, and flake-like graphite were used in this work. Comparative assessment of morphometric characteristics of particulate fillers: area, perimeter, equivalent diameter, shape factor and their distribution on these indicators were performed by methods of optical microscopy and image analysis. Composite films based on LDPE, containing 5% vol. with different types of conductive fillers were obtained by pressing method. It was found that the nature of the filler quantitatively influences on the uniformity of distribution of its particles in composite films. The most structural homogeneity was observed in PE-Gr and PE-Cu composites, while the least - in PE-Br composite. It was shown that the increasing of average particle anisotropy for investigated fillers reduces their heterogeneity of distribution in composite films.

The purpose of this study was to develop and characterize the in vitro release kinetics of erythromycin from water-in-oil microemulsion preparations for dermal application. The results obtained confirm that the water-in-oil microemulsion systems based on avocado oil can be used as incorporation and delivery systems for the topical administration of ER in the treatment of skin disorders.

This study reports on the in vitro erosive capacity of three different pH chlorinated waters on dental enamel, and the anti-erosive protection conferred by three dental materials (toothpaste, remineralising cream, and fluoride varnish), assessed by scanning electron microscopy. Fluoride varnish provided the best protection, forming a resistant thin film on the enamel’s surface. The observed ultrastructural changes of the enamel surface were low when the tooth paste was used, and more pronounced when the remineralising cream was used.