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The aims of our study were to assess the cytotoxic effect of five orthodontic bonding materials, in vitro, on HUVECs to study the induction of apoptosis and inflammatory response generated to assess the shear-bond strength of the 5 tested materials in order to quantify their performance. Standardized samples from each material were obtained and incubated with HUVEC cells for 24 and 72 h immersed in complete medium. Cell viability was determined by means of MTS method. Active caspase 3 and TNFa protein levels were measured through ELISA techniques. The shear-bond strength was tested on 60 extracted premolars which were bonded with the same type of bracket, using the 5 different materials. Statistical analysis Student T-tests, Chi-square and Anova tests were used for results interpretation. Cell viability was decreased with material exposure in a time dependent manner. All materials exerted cytotoxic effects, the experimental materials showed a significantly higher decrease in cell viability at the 72 h reading. Shear Bond strength was superior for the resin commercial bracket-bonding materials. The study shows that orthodontic adhesives’ cytotoxicity and physical performance is related to their chemical properties and proves that all orthodontic practitioners should use freely their material of choice on condition they are aware of all its’ properties.

The thoracic wall resections for tumoral affections are laborious surgical interventions characterized by a high mortality and mobility. In order to create this paper we created a observational retrospective study in which we included 21 patients that have underwent parietal thoracic resections for tumoral affections. In all the patients we practiced the reconstruction of the thoracic wall using polypropylene mesh. The main postoperative complications were: seromas (14.28% of the cases), hematomas (9.52% of the cases), wound infection (4.76% of the cases), pneumonia (23.8% of the cases), respiratory failure (23.8% of the cases), paradoxical movement of the thoracic wall (52.38% of the cases). No deceases were recorded. In conclusion, the use of polypropylene mesh in the reconstructive techniques of the thoracic wall after thoracic wall resection represents a viable method, with good respiratory functional results.

Polyelectrolyte multilayer capsules are synthesized comprising of 12 total layers each containing a single layer of iron oxide nanoparticles in shells 4, 6, 8 or 10. A protein-labelled dye is embedded in the calcium carbonate template core as a model for the encapsulation of a drug. The core is dissolved after 6 layers are formed. Two types of magnetic nanoparticles are incorporated into various capsule shells: ferric oxide (Fe2O3, 50 nm) and iron oxide (Fe3O4, 15 nm), a 1:1 (vol.) mixture of the two types of nanoparticles suspensions is also used. Nanoparticle inclusion reduces the capsule sizes in all cases with the order of effect Fe3O4 [ Fe2O3 [ Fe2O3/Fe3O4 mixture. When Fe3O4 or a Fe2O3/Fe3O4 mixture is incorporated in layer 6 the reduction in size of the final capsules is less than expected. The number of surviving capsules containing nanoparticles are lower than control regardless of which of the nanoparticles is used but here the effect of Fe3O4 or a mixture of the two types of nanoparticles incorporated in layer 6 was slightly out of step. The amount of iron incorporated is almost the same regardless of which shell the nanoparticles were incorporated but the iron content using 50 nm nanoparticles is generally slightly higher than that obtained with 15 nm nanoparticles.

Stress urinary incontinence in women is a condition widely encountered in the entire world with a prevalence between 12.8% and 46.0%. Stress urinary incontinence is a public health problem causing a significant decrease in quality of life, involving social, physical, psychological, occupational and sexual suffering of patients. The minimal invasive treatment of the stress urinary incontinence (SUI) consists in fixing a suburethral polypropylene mesh (SPM) in retropubic (TVT) or transobturator (TOT) space, in order to regain the pelvic support of the urethra, with the consecutive augmentation of the pressure of urethral closing during effort. The objective of this paper is to present the advantage of SPM in the SUI treatment in the eleven years’ experience of Department of Urology Sibiu.

The paper presents experimental results on the mechanical behaviour for a polymer based composite sandwich panel tensile and bending tested, which uses, one by one, a cellular composite core fabricated by additive manufacturing of four different types of polymeric materials: ABS (acrylonitrile butadiene styrene), PC (polycarbonate), PLA (polylactide) and CF (polylactide + 40% carbon fibre), with the thickness of 3 and 5 mm. This research focuses on comparative analysis of the core thickness increase effect on the structure’s strength. Experimental tests carried out on standardized test-pieces with specialized laboratory equipment, are highlighting similar mechanical behaviour and are showing also an increase of composite stiffness with the increase of core thickness, at the same time, the arrangement of the cellular lattice structure has a significant effect on the structural strength.

Most studies and experimental tests performed upon orthopaedic bone cements are related to their use in everyday conditions when usual wears are due to compression and fatigue. The present paper deals with some special situations occurred during the patient’s recovery after the surgery. The recovery activities and motions may induce different types of loads, like tensile, during stretching and relaxation techniques, especially in the joint insertion area. These situations are insufficiently researched, but they represent one of the main concerns of the medical staff involved in recovery and rehabilitation. Besides the study of mechanical properties for these special situations the paper proposes also a thermal analysis during preparation of the polymethylmethacrylate(PMMA) as it can be the trigger of serious health issues (necrosis, blood circulation problems, BCIS, etc.) due to the exothermic polymerization reaction. The monitoring method proposed for the temperatures developed during the polymerization may avoid the aforementioned issues.

Difficult airway management is a common situation when the anesthesiologist deals with patients with hypo pharyngeal tumors. The volume of the tumor usually covers the glottis plan and modifies the local anatomy, making the intubation process difficult or almost impossible. Intubation laryngoscopes developments are minor and adding a CCD camera at the tip of the laryngoscope is the best improvement made in our days. Today, on the market, an intubation device designed properly for the patients with extensive hypo pharyngeal tumors does not exist. The aim of the paper is to present an innovative device designed for patients with hypo pharyngeal tumors.

Polymer microstructures containing plant extracts are a novel technique used to increase the bioavailability of active agents with low aqueous solubility. Japanese knotweed (Reynoutria japonica) is an invasive plant with multiple biomedical properties. The aim of the present study was to obtain and characterize polyurethane microstructures used as a drug delivery system of a Japanese knotweed extract. The results indicate the obtaining of microstructures with an almost neutral pH, with sizes between 540 and 1134 nm, with a medium stability against the tendency to form clusters and a very good thermal stability. These first results present the potential of the obtained polyurethane microstructures as candidates for the transmembrane drug delivery of Japanese knotweed extracts, as a starting point for further bioactivity investigations.

Microfibers were obtained from organic low molecular weight compounds based on heteroaromatic and aromatic rings connected by aliphatic spacers. The obtaining of microfibers was proved by scanning electron microscopy. The deciphering of the mechanism of microfiber formation has been elucidated by X-ray diffraction, infrared spectroscopy, and atomic force microscopy measurements. By exciting with light of different wavelength, florescence microscopy revealed a specific optical response, recommending these materials for light sensing applications.

Nanocomposite materials have attracted a high interest for biomedical applications because their special properties related with structure and composition. In this paper we synthesized novel hydrogel nanocomposite materials special designed for hard tissue engineering. The nanocomposite materials are able to promote hydroxyapatite formation by alternating soaking mineralization demanded for increasing of cells biocompatibility and adhesion.