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3D printing paired with CBCT imaging technology could provide a more individualised approach to orthodontic diagnosis and tratment. The aim of the present study is to asses dimensional differences between the CBCT image and 2 types of 3D printed replicas of an impacted maxillary canine, and to determine whether this method could be used in the future development of customised orthodontic attachments. Ten replicas were printed using the STL file of the impacted canine using two types of resin- five of each, with the same printer. Linear measurements of maximum height, length and width, were made. Mean dimensional erorrs were 0.184 mm and 0.068 mm. The largest discrepancy was in lenght - 0.362 mm. More reasearch is needed, but in this study we obtained printed resin replicas that provide sufficient dimensional accuracy to be used in orthodontics.

In the second part of this series polyelectrolyte multilayer capsules consisting of 6 bilayers of PAH/PSS and one layer of magnetic iron oxide nanoparticles namely D12, were fabricated. These capsules had their inner core removed once the 12 layers had been formed. The properties of the D12 capsules (mean diameter, concentration, dye intake and iron content) were analysed and compared with previously manufactured capsules which had the core dissolved after only 6 layers of coatings namely D6. The new sets of capsules had a greater capsule diameter, higher dye intake into the core and a higher iron oxide loading into the capsule layers.

The aim of this experimental study is to compare the biointegration and tissue response to different surgical mesh types, inserted in various layers of the abdominal wall of Wistar rats. After 30 days, the rats were sacrificed and the meshes were removed en bloc with the subcutaneous tissue, muscular layer and peritoneum. Tissue response (fibrosis, inflammation) was measured using quantitative and semi-quantitative morphometry. We observed that polyethylene terephthalate 3D mesh induces significantly more fibrosis compared to polypropylene mesh and the fibrosis is absent or minimal in case of the control group. Tissue reaction, including fibrosis, is reduced around the polypropylene mesh. We also observed that fibrosis is more intense towards aponeurosis and peritoneum. We can conclude that the 3D mesh shows better biointegration if it is used in proper circumstances. It’s well tolerated by the organism if sutured to the aponeurosis and preferable with monofilament stitches.

ATR / FTIR and DSC techniques have been used to evaluate the thermal stability of some ageing paint materials by heat treatment while immersion in natural ester-based electro-insulating oil. Experimental determinations have highlighted the fact that the investigated paint materials (epoxy resins) have a high oxygen affinity and thus, in closed systems (such as power transformers), they oxidize before coming into contact with the transformer oil. This behavior indicates that the paint layer (suitably chosen) applied on the inside of the transformer vat functions as an antioxidant and results in increasing the thermal stability of the oil.

Incisional hernias affects approximately 10-20% of patients with history of abdominal surgery. The purpose of this study was to examine the tissue integration of the polypropylene mesh in patients operated for strangulated incisional hernias to those operated for uncomplicated incisional hernias. For this purpose, we introduced 218 patients with surgical treatment of the incisional hernia with polypropylene mesh. The total number of patients studied was divided into 2 lots: group A consisting of 189 patients with uncomplicated incisional hernia and group B of 29 patients with strangulated incisional hernia. We studied separately the local postoperative complications in the two groups (hematomas, seromas, abdominal wall infections). Although the number of local postoperative complications was higher for group B, the differences were statistically significant only for the incidence of abdominal wall infections. Although the use of the polypropylene mesh in the surgical treatment of strangulated incisional hernias predisposes to a higher risk of local postoperative complications compared to its use in the surgical treatment of the uncomplicated incisional hernias, its use in the surgical treatment of the strangulated incisional hernias is beneficial.

The paper shows the importance of designing an ABS (Acrylonitrile-Butadiene-Styrene) plastic part which will be produced using FDM (Fused Deposition Modeling) technology; it is obtained a product with the same characteristics provided by the operating guide book. Thus, this solution combines both the capacity of the designer as well as the applied technology and can produce similar or improved plastic components, at the same time maintaining the functional characteristics of the work piece. This paper is a plea for the application of 3D printing using FDM technology for manufacturing components (spare parts) out of production, because the technological systems users no longer have other solutions available for replacing outworn plastic parts. 3D printing using FDM technology is a fast option for replacing outworn components, the modeling, simulation and printing time being shorter than the purchase time of a new subassembly or assembly that has been remanufactured and modernized.

In this paper, the authors show a part of research works performed on the use of 3D scanners and 3D printers to execute plastic parts with complex surfaces. 3D scanning allows copying of certain surfaces in our environment, based on existing models. Scanned models may represent various objects, made of a wide range of materials: metals, ceramics, fabrics, plastics, leather, organic materials etc. [1]. This paper shows the results achieved using a scanner and a common and affordable - low-price - printer. 3D scanners and printers allow execution of clones of certain parts with irregular surfaces.

Structural elements of special industrial constructions can be often subjected to time variable stresses. One of the main stress is the snow action, which is considered to be one of the most severe tests. In the study, the static snow action on a tank cover from a pickling plant on the ArcelorMittal Galaþi platform is analysed. The material structure of the cover is sandwich type with skins made of steel /layered composite and core made of polystyrene foam. The purpose is to determine, by FEM analysis, the deformation mode and the stress condition of the cover under the action of load, for two models of sandwich type structures, steel-polystyrene-steel, respectively composite-polystyrene-composite, with different faces thicknesses and cores. Panels are applied simulative a load of snow of different thickness, the distribution of snow on the surface of the panels being considered uniform in order to determine an optimum combination of faces and core thickness as well weight and economic cost too. Numerical analysis models with finite elements of SHELL 3L sandwich type structures are used.

Urinary incontinence is one of the most common diseases, 25% of women between 18 and 80 years suffer from it. Urinary incontinence can be described as accidently loss of small amounts of urine. The solution involves a surgical procedure, such as sling procedures and bladder neck suspension procedures. The methods of surgical interventions have evolved due to a minimum period of hospitalization (sling, TVT), or performing laparoscopic surgery instead of the classical Burch surgery. Studies reviled that the most effective interventions are those which restore the urethra by retro pubic urethropexy, pubovaginal sling and synthetic mid-urethral slings. This type of surgery has currently the highest success rate (85-90% on 5 years after surgery), and the lowest relapse rate. In our study we obtained the same success rate for the TVT procedure.

The purpose of this in vitro study is to evaluate the marginal percolation-micro leakage by comparing the possible infiltration of ionomer cement filling which was used to restore a class I cavity prepared by classic conventional method – diamond bur versus Er:YAG laser irradiation treatment. Ten molars were included in this study. The molars were random divided in two groups: group 1 - laser treatment and group 2- classic conventional treatments. The teeth were immersed in methylene blue solution for 24 h. Afterwards, the molars were vestibulo-oral sectioned through the centre of each restoration in order to see any signs of marginal percolation. The marginal percolation observed was more significant in conventional preparations group than in laser’s group. The glass ionomer cement remains one of the most adequate restorative materials to be used on deciduous molars when micro infiltration is questionable.