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The aim of this study was to asses the flexural strength of provisional acrylic resin fixed partial dentures reinforced with glass fiber with the provisional restorations without reinforcement. Three group of specimens were prepared for the flexural strength: Poly Methyl Metacrylate (PMMA) acrylic resin provisional restoration without glass fiber (control), acrylic resin provisional restoration reinforced with glass fiber between the abutments and acrylic resin provisional restoration reinforced with glass fiber including the abutment and the pontic of the fixed partial denture. The flexural strength was tested with a servo-hydraulic testing machine (Zwick Proline Z005 device), with a maximum 5KN force The highest resistance to deformation and fracture was registered in acrylic resin provisional restoration reinforced with glass fiber including the abutments.

In present paper there are given the results concerning wear behaviour in Ringer’s solution of four titanium alloys with 5%Mo, 7%Mo, 11%Mo and 12%Mo. Structural investigations (made by both optic, electronic microscopy and X-Rays diffraction) revealed a dual phase structure consisting from alpha martensite and beta”solid solution, with the constituents proportion depending on molybdenum content. Wear rates were determined using a Talysurf profilometer in Ringer’s solution for the experimental titanium-molybdenum alloys. Finally, the beneficial influence of molybdenum on wear behavior was put in evidence: the higher molybdenum content is, the lower friction coefficient is.

A novel assay for the electrochemical detection of 4-nonylphenol (4-NP) based on carbon nanotubes modified screen-printed carbon electrodes (CNTs-SPCEs) has been investigated. The electrochemical behavior of the modified SPCEs and the mechanism of the oxidation of NP were investigated using cyclic voltammetry. The differential pulse voltammetry parameters were optimized for quantitative determination of 4-nonylphenol. A detection limit of 9.95·10-6 mol·L-1 was obtained for 4-nonylphenol using its oxidation signal at +0.25 V. The disposable sensor showed good performance and was applied for the determination of 4-nonylphenol in tap water with satisfactory results.

The obtaining of polymers with special properties is dependent on both conditions and materials used in the formation process. This work presents the obtaining, by using the sol-gel method (and citric acid used as in mixture fuel), of some powdery materials destined to be used as additives in polymers’ formation. Different types of salts were used in the powders’ obtaining process, the long term purpose being to add special properties to polymeric materials, such as good electrical conductivity or photovoltaic capabilities. The materials and methods are thoroughly presented, proving the obtaining repeatability of these powders. Different characterization techniques were used and presented in this paper, from Scanning Electron Microscopy (SEM) for morphology, to EDX for elemental composition, Raman scattering for vibrational properties, thermal analysis by differential scanning calorimetry (DSC), and electrical resistivity for electrical conductivity calculation.

Surgical sutures properly conducted will ensure maintaining the edges of the flaps until the wound healing process allows withstanding the functional stress. Among the possible complications of surgical sutures, we can find the wound suppuration, as a result of contamination with germs. In our in vitro study about the degree of bacterial adherence to different types of suture materials we chose four types of suture materials (three absorbable and one nonabsorbable) exposed to 4 bacterial species (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa). The monofilament absorbable polydioxanone wire had the lowest bacterial adherence, followed by the multifilament nonabsorbable wire of silk and the two types of multifilament absorbable polyglycolic acid wires. Regarding the bacterial species tested, Enterococcus faecalis had the highest adhesion level, no matter what type of material or time of exposure has been used.

Because the petroleum based products have a negative impact on the environment,is necessary to create and use eco-friendly lubricants. Vegetable oils are part of this category because they are a renewable natural resource, environmental safety, and show lubricating characteristics. By mixing the castor oil with two synthetic diesters (isodecyl and 2-[(p-nonyl)phenoxy]ethyl adipate respectively, isotridecyl and 2-[(p-nonyl)phenoxy]ethyl adipate) were obtained two series of new lubricants to which the physico-chemical and rheological characteristics were studied. The lubricants were also characterized using the differential scanning calorimetry (DSC) and thermal gravimetric (TG) analyses. The obtained mixtures present superior properties to mineral oils and can be used as lubricants.

Ferrites are generally used to obtain soft magnets for domestic or industrial applications but their use in this direction had generated an increasing interest in modifying the polymer properties by dispersing in their volume certain amounts of these ceramic compounds. Of course one issue of each researcher is to find a way or a technique to orientate the ferrites particles inside the polymer matrix to obtain structures able to respond to application of an external magnetic field. The use of ferrites nano-sized particles is facilitating their uniform distribution inside the polymer and, because of the viscous properties of pre-polymer mixture, is avoiding their aggregation. One way to create oriented distributions of the nano-particles is to use external magnetic fields during polymerization such as, at the end of process, they will be kept in fixed position inside the polymer network. The current study is about electrical properties induced by the presence of nano-sized strontium ferrite and barium ferrite in an epoxy matrix. Three types of epoxy resins had been used with 5% weight ratio of each type of ferrite and 10% weight ratio when both ferrites were used to modify the properties of the same polymer matrix. Electric conductivity had been studied by two methods – one on steady-state regime and one in variable regime. Using the variable measurement of electromagnetic properties the dielectric permittivity and the magnetic permeability were also determined.

The paper represents a third part from the series, and refers to the elaboration of the experimental protocol regarding the use of Iosipescu test in the optimization of the structural-constructive characteristics of the matrix biomaterials for removable prosthetic restoration. The way the samples were consolidated with aluminum plates, at the clamping ends, was established through traction and shearing tests. Based on the theoretical protocol, the following were determined: the shape, size and loading of the Iosipescu sample, alongside with the bridge calibration. The gathered experimental data were used to evaluate the behavior of the CT-1 silicon adhesive. The paper focuses on the design of the samples used for the traction and shearing tests, made out of biocompatible polymer composite materials .Their structural and feasible behavior is influenced by the adhesion between layers, and by the gluing capacity of the used adhesive. The purpose of the paper is to enhance the performance of polymer composite materials, by using a compatible adhesive in creating a finite modeling element for standard single traction and shearing resistance tests. A tridimensional model of a longitudinal sample that underwent stretching and shearing test, while applying quasi centric loads, was elaborated and the main characteristics of the adhesive and of the glued interfacial area, that influence the structural and functional performance, were analyzed.

Morphological restoration of the face in complex tissue defects involving midface remains a great challenge for any surgeon. Tridimensional tomographic analyze gives excellent quality images of the defect and modern technology can provide prosthesis for skeletal replacement at least. Prelaminated free flaps are a method to reestablish morphological aspect and restore lost functions. We describe here a case of 30 years old male patient, victim of a self-inflicted gunshot wound, with a complex defect of the midface. A three-dimensional skull reconstruction was performed in order to restore the midface morphology. Following an initial uneventful evolution, at 2 weeks we noticed partial flap necrosis, with a small island of implant denudation in the mouth and significant decrease of the hypodermis, but with the integrity of the skin covering the implant. Despite of this, we observed a good general condition and improvement of patient’s mental health, swallowing restoration and phonation improvement.

Alopecia areata is the most important inflammatory alopecia, caused by immunological factors, genetic factors, emotional factors, endocrine dysfunctions, infectious foci, nutritional deficiencies, and the harmful action of various environmental stimuli. The use of aggressive shampoos, of inadequate cosmetic and styling products, hair dyeing and waving, external pollutants might participate in the physiopathology of alopecia by sustaining inflammation, disturbing the local microcirculation, promoting oxidative stress. The aim of this study is to verify the hypothesis that oxidative stress might influence the progression of alopecia areata. Regulating the possible identified imbalances in alopecia areata might represent a means of preventing or improving this disorder.