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This work has described the production of single-polymer composites by the film-stacking method. Two types of single-polymer composites with different mass fractions of the polyester reinforcement phase (10% and 20%) and the PETG matrix were investigated. The produced composites were subsequently recycled by injection moulding, pressing, and extrusion. Selected properties of the processed composites were determined: density, viscosity-average molecular weight, impact resistance, and tensile strength. The work done in this paper has demonstrated the benefits and drawbacks of each recycling method for these materials. The selected properties of single-polymer polyester composites and single-polymer polyester composites that were recycled by extrusion have also been compared.

The purpose of this study was to determinate , using the Finite Element Analysis Method, the mechanical stress in a solid body , temporary molar restored with the self-curing GC material. The originality of our study consisted in using an accurate structural model and applying a concentrated force and a uniformly distributed pressure. Molar structure was meshed in a Solid Type 45 and the output data were obtained using the ANSYS software. The practical predictions can be made about the behavior of different restorations materials.

Selection of sealing material is a problem in terms of long-term durability. In this regard, we have been investigating the in vitro structure and in vivo retention of composite resin sealant with BIS-GMA. Bi-dimensional and three-dimensional analysis by AFM highlights a homogeneous structure with no structural retaining areas of the material. Comparative in vivo and vitro evaluation of sealing resin revealed a correlation of the analyzed aspects in terms of the retention of the material used.

The aim of this experimental study is to reveal the design and characteristics of unipolar shoulder prosthesis type Arrow (Groupe FH®, France) as well as to evaluate the outcome of the proximal humerus fracture treated with this implant. 8 patients with a mean age of 62.5 years were operated with immediate passive rehabilitation and active exercises initiated around day 45. All patients had good results with minimal pain, a mean Constant - Murley score of 74 and an acceptable shoulder amplitude. The clinical success was assured by the anatomic union of the tuberosities around the implant. The Arrow metaphyseal corundum blasted humeral titanium stem assures a perfect osseointegration with optimal stability and is an efficient alternative for shoulder hemiarthroplasty.

This paper proposes to investigate in detail the behavior of polymeric membranes ultrafiltration process uses in the retention of humic acid from aqueous systems. Nowadays, the aqueous systems (contaminated water and/or wastewater) resulting from various domestic and industrial activities contain many contaminants, some of them increasingly dangerous to the environment. Laboratory testing of membranes in the ultrafiltration process as well as their experimentation with different chemical compounds is essential because it is important to know how they can be eliminated before they cause a negative impact. Testing of polymeric membranes consists in carrying out the process of ultrafiltration of aqueous systems containing humic acid over a set time, following the variation in time of the volume of permeate obtained as well as the influence of process parameters. Following the investigation of the ultrafiltration process of the water through the polymeric membrane, it was found that the formation of the humic acid layer on the surface of the membrane that favors fouling is delayed, after many hours of operation, due to both the internal fiber structure which offers advantages to this type of membranes as well as high efficiency of humic acid retention. Experimental results showed that the humic acid retention rate increased by up to 37% as a result of the double decrease of the conductivity value in the permeate samples from about 600 mS/cm to 373 mS/cm and the temperature being continuously increasing, from 22.5 at 25oC over 5 h influenced the entire ultrafiltration process. The full process approach as well as the expression and interpretation of the results will be detailed in this paper.

The large diversity of clinical forms in Angle second class malocclusion explains the interest of researchers and clinicians in identifying changes in the dental arch in subdivisions II/1 and II/2. The purpose of the study is to identify the characteristics of the dental alveolar arch in order to determine the differences between class II/l and II/2 malocclusions. The study was conducted on dental gypsum models of 62 orthodontic untreated patients diagnosed with class II/1 Angle malocclusion, respectively class II/2. The results obtained by us reveals a statistically significant differentiation in the dental arcade, a narrowed maxillary arch at the molar level and elongated at premolar and molar level, in subdivision II/l. Our data are consistent with the results of literature. The knowledge of dental arch features serves to develop a correct and complete diagnosis and also to reach the therapeutic goals and to evaluate post-treatment response in short, medium and long term.

The use of collagen scaffolds and stem cells for obtaining a tissue-engineering complex has been an important concept in promoting repair and regeneration of the bone tissue. Such units represent important steps in the development of an ideal scaffold-cell complex that would sustain new bone apposition. The aim of our study was to perform a histologic evaluation of the healing of critical-sized bone defects, using a biologic collagen scaffold with adipose-derived mesenchymal stem cells, in comparison to negative controls created in the adjacent bone. We used 16 Wistar rats and according to the study design 2 calvarial bone defects were created in each animal, one was filled with collagen seeded with adipose-derived stem cells and the other one was considered negative control. During the following month, at weekly intervals, the animals were euthanized and the specimens from bone defects were histologically evaluated. The results showed that these scaffolds were highly biocompatible as only moderate inflammation no rejection reactions were observed. Furthermore, the first signs of osseous healing appeared after two weeks accompanied by angiogenesis. Collagen scaffolds seeded with adipose-derived mesenchymal stem cells can be considered a promising treatment option in bone regeneration of large defects.

The drug carriers represent a very important and modern pathway used to increase the therapeutic efficacy of the natural active substances. Nano-sized assemblies of noble metals and herbal extracts represent very simple, cheap, biologically and ecologically friendly synthesis. The main aims of this study were to obtain polyurethane nanovesicles containing silver nanoparticles and to evaluate their release rate. The vesicles’ sizes, homogeneity and surface charge were studied using a Cordouan Technol. Zetasizer, while the thermal behaviour was assessed by DSC. UV-Vis measurements were done to evaluate the release rate. Toxicological effects were studied by non-invasive techniques on human skin. The results suggest the obtaining of homogenous polyurethane nanovesicles between 80 and 95 nm, with positive surface charge, very good thermal stability and a prolonged release. The non-irritation potential recommends these vesicles as a safe carrier for different herbal extracts.

Sewage sludge resulted from urban wastewater treatment plants is generally accepted as a valuable source of nutrient and soil conditioner for agricultural usage. Analysis of amount of heavy metals in sewage sludge is essential previous to utilization of the sludge to agriculture considering the inevitable risk of heavy metal toxicity to soil, vegetation and humans. The present paper aims to analyse the characteristics of the sewage sludge resulted in an urban area for 5 years. Sewage sludge generated from five wastewater treatment plants in the South and South Est part of Romania were analysed.

In total edentulous treatment can be used a variety of means capable to reconstruct through artificial prosthetic devices the edentulous dental arches, in an individualized manner depending on the clinical situation, objectives and criteria for treatment. The present study was intended to evaluate the effectiveness of general treatment with vitamin B12 and the effectiveness of local treatment, achieved through complete dentures and to emphasize the much easier and cheaper way to do the same treatment over the same time period.