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Using antibiotic impregnated cement is an important mean to treat and prevent periprostetic joint infections. This complication requires for treatment important financial and technical resources. Adding antibiotics to orthopaedic cement may alter its mechanical properties with possible reduced time of prosthesis survival rate. This study analyze the mechanical properties of cement mixed with antibiotics in the operation room, which helps reducing costs and permit a more specific antibiotic local therapy. All tested antibiotics used in this study does not change the mechanical behavior of the orthopaedic cement when mixed in therapeutic doses, all alterations seems to be at a level below clinical significance. Mixing antibiotics in Orthopedic cement leads to minor decrease of the mechanical properties for cefazolin, cefuroxime, ceftazidime, meropenem and vancomycin and a mechanical significant decrease for gentamicin and clindamycin.

In the paper, a new Euler-Bernoulli theory is presented, in which the bars eigenpulsations with rectangular section increase with the ratio between the bar width and thickness. This theory is experimentally verified for composite bars made of Dammar reinforced with cotton and flax plus one or two layers of fiber glass fabric. For the considered bars, we have experimentally determined the eigenfrequencies and the damping factor values. We have experimentally determined the Young modulus and breaking strength for the used resin and the obtained composites.

The influence of aluminosilicates on the structure and drug release profiles of polyvinyl alcohol (PVA) – halloysite (HNT) hydrogels containing acetylsalicylic acid (ASA) as a model drug was monitored. The hydrogels were synthesized using a three cycle freeze – thawing procedure and were characterized by FTIR, XRD and SEM. The swelling degree and cytotoxicity were also determined. All hydrogels properties were influenced by HNT concentration from the polymer matrix. The release of ASA, from PVA – HNT hydrogels was monitored in the gastrointestinal tract conditions.

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.