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Verteporfirin is the active substance of the medicine Visudyne (the basic form porphyrin of the medicine) approved and in use for ophthalmic diseases and tumor types. Because the informations from literature about degraded of this porphyrins are greatly reduced, we propose in this paper to separate the different degraded forms of this porphyrin by using polysulfone membrane polymer type. In this paper are presented some analytical results of verteporfirin before and after passing degraded form of the porphyrins over these membranes.

This paper presents a modification study of recovered polypropylene by melt alloying with a styrene-isoprene block-copolymer blend, thus ensuring the optimum conditions to obtain polypropylene composites with performance impact strength.

The paper describes the investigations related to the fabrication and characterization of two new plastic pyrotechnic compositions using solvent-free polyurea as binder. These solvent-free polyurea binders allow wet or dry pressing of the pyrotechnic compositions. The rubbery texture of the polyurea binders minimize the risks associated to the dry pressing of other brittle binders. A comparative theoretical and experimental study between these new types of binders and a conventional binder has been performed, in order to establish the improvements that could be brought to the pyrotechnic compositions, in terms of safety and performance.

The aim of this study was to achieve a polymeric scaffold, ex-vivo, using 3D printing technology and then subjecting it to various tests to check its optimal property. Initially there was selected a lower jaw with a bone defect that would have prevented any treatment based prosthetic implant. The mandible was first scanned using an optical scanner (MAESTRO DENTAL SCANNER MDS400). The scanning parameters using optical scanning system are: 10 micron accuracy, resolution 0.07 mm, 2 rooms with High-Resolution LED structured light, two axes. The scan time of the mandible was 4-5 min. Later the same mandible was scanned using CBCT’s CRANEX 3DX. The images obtained using CBCT’s were correlated with those obtained by optical scanning. Further on, there was achieved the digital design of the future scaffold with the conventional technique of wax addition directly on the mandibular bone defect. After that, this was again scanned using scanning system MAESTRO DENTAL SCANNER MDS400, and using CBCT’s CRANEX 3DX. The images obtained were correlated with all the scanned images of original mandible bone defects. There were made two polymeric scaffolds using 3D printing system an (D20 Digital Wax System 3D Printer). After printing, scaffold sites were introduced for 30 minutes in an oven curing. Later the pieces obtained were processed to remove small excesses of work. There were obtained 3 blocks of polymers that have a good adaptation to the bone profile. Often, in oral implantology and maxillofacial surgery appear bone defects. They prevent an optimal treatment of bio-functional and aesthetic restoration. Using 3D printing technology one can achieve scaffold sites of different biocompatible materials that have optimal properties to replace bone defect and restore the defective area. These scaffold sites have an intimate adaptation to the defect. 3D printing techniques used to restore bone defects can quickly and efficiently give the possibility to have a successful implantology prosthetics treatment.

Fabrication of temporary restorations is an essential part in dentistry and especially in oral implantology. Polymethyl methacrylate is used for a long time as material for temporary restorations and many improvements has been done to increase its properties, especially fracture resistance. Crosslinking and computer-assisted design/computer-assisted machining permit fabrication of long-term temporary restorations with flexural strength high enough and good modulus of elasticity that do not fracture easily under functional loads.

This study intends to highlight the results of the product Teosyal Redensity II through the cumulative effects of its constituents, that have an antioxidant, hydrating, filling and facial restructuring role. The study was performed in the Arestetic Clinic, Galai, between 07.12.2015 and 07.12.2016 on a group of 49 patients, of which 43 women and 6 men. Teosyal Redensity 2 proved to be a safe product – as long as it is injected correctly, it does not cause complications. It’s easy to inject and has a very high efficiency. It’s a periorbital rejuvenation and restructuring product, with a filling, antioxidant, hydration and dermal redensification effect. In the case of persons that needed a second injection after 1 month, one could observe a major improvement in elasticity and firmness felt by the person performing the injection. The injection requires small quantities of the substance and is accompanied by only mild discomfort. The result is visible right away.

This paper deals with the synthesis of polyurea and its use as polymer matrix for nanocomposites reinforced with multi-walled carbon nanotubes (MWCNT). Two types of materials were obtained during this research, the first cathegory uses the polyurea as matrix and the second one uses a mixture between epoxy resin and polyurea. The nanocomposites were characterized by Thermogravimetric Analysis (TGA), Dynamic Mechanical Analysis (DMA), Scanning Electron Microscopy (SEM) and Tensile Tests .The elastomeric features of nanocomposites were highlighted by the results which showed low value of Tg. Also higher thermal stability with ~40oC compared with commercial products (M20) were observed, but lower mechanical properties compared to neat polyurea.

Post and core build-ups provide resilience and retention for future tooth restorations. In this study we intend to assess the resistance to fracture of two types of aesthetic post, using a testing machine after the application of a paraxial force. The results show that no specific material from the ones used shows a better behavior. Fiber quartz posts AAA Fiber Post had the highest resistance and the fiberglass posts Matrix Plus 2 were rated with the lowest values. Further laboratory and clinical studies are necessary to the in which one type of post material is favorable for a specific type case.

The Gold standard in parietal wall hernias is represented by mesh implantation. Both wall repair and hernia-associated complications are related to the anatomic location and biomechanics of the structures involved specificity. This work reports the results of the intraoperative and postoperative evaluation of synthetic polypropylene mesh integration. The mesh and the surrounding tissue, previously removed and preserved, have been analyzed macroscopically and at microscopic level. The tissue invaded the pores of the mesh and coated the monofilaments. The right balance between the mesh type and tissular response is hard to evaluate preoperatively, due to individual variations, but we can upgrade the criteria used to personalize the treatment for the best possible outcome.

The article presents the procurance of an apparatus intended for the stage of reading and writing , used both by the pre- school children and the persons who present speaking deficiencies ,obtained from plastic parts marked and processed using a laser equipment. The learning equipment of writing and reading consists in a carcass of a triangular prism which has on a lateral side two visualization windows and a magnetic plate for writing, placed one below the other, at an appropriate distance, each visualization window being equipped with several illumination sources, disposed in a lineal way along the window, having an independent performance.