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Present requirements of the modern man impose the realization of textile products with an increased comfort that should provide, besides their basic functions, the conditions of easy motion, aesthetic aspect, easy maintenance etc. These requirements are conferred by the textile products containing elastomer. The development of elastomer fibers and filaments based on polyurethanes, as well as the progress in textile mechanical and chemical technologies, offer the possibility to obtain textile products with increased elasticity. Wool-types yarns with different torsion degree (twist factor 72÷128) and elastomer content between 4.5 and 11.5% have been realized. This work studies the influence of torsion degree and the elastomer content on yarn characteristics.

An organic–inorganic conductor’s Polypyrrole(Cl)/Zeolite 4A (PPy(Cl)/Z4A) was successfully synthesized by chemical oxidative polymerization at low and room temperature, using FeCl3 as initiator the reaction and dopant at the same time. After characterization, commodity we methods primarily on the polymerization of pyrrole with different molar ratios of [FeCl3]/[Pyrrole] in an aqueous medium, followed by a series of characterizations for the polymers obtained. The right ratio was used for the preparation of nanocomposites PPy(Cl)/Z4A. After each synthesis, the developed product is characterized by FTIR, SEM-EDX, XRD, electrical conductivity and cyclic voltammetry, in order to confirm the success of the process of synthesis and study their properties to specific applications envisaged.

Dental implantology is a frequently applied method for prosthetic restoration of edentulous dental arches. In the past 50 years it has been evolving most dynamically among other branches of dental sciences. According to several reviews and meta-analysis of literature, it seems that the most predictable phase that influences success rate of dental implants is limited only to the surgical stage of treatment [1]. The long term success of dental implants is highly influenced by their biomechanical behaviour, load transfer and osseous tissue reactions to local mechanical tensions around dental implants [1-3]. This in vitro study was aimed to investigate and locate peak tensions inside the fixating substrate of dental implant intimacy. Three root form dental implants were installed, with 14 mm length and 4.5 mm diameter, in tripodistic alignment in a highly rigid and resistant plastic sheet (Araldit-D) also used for photo-elastic measurements. The dental implants were compressed simultaneously and grouped with linear, vertical forces. The mechanical stress distribution and the displacement field of the fixating substrate were analyzed with Digital Image Correlation method (DIC). This modern, non-contact optical investigational method offers highly accurate measurements with great precision (in order of microns, mainly pixel by pixel) practically eliminating all disadvantages and limitations of the most used, classical, experimental methods [4, 5]. Peak tensions were found at the neck area of this type of dental implants. The thickness of the fixating substrate influenced more the appearance of peak tensions rather than the distance between two dental implants. Tripodistic alignment of dental implants might be reconsidered in areas where bone thickness is limited. Virtual, biomechanical simulations should be used in future for surgical treatment planning.

The aim of this study was to assess the effect of toothbrushing with toothpastes having different relative dentine abrasivity (RDA) and toothbrushes having different bristles hardness on different composite resins, compomers and traditional glassionomer cements by surface roughness evaluation. All the samples were evaluated regarding the surface roughness using roughness checker (Taylor Hobson-Surtronic25, AMETEK Inc., Pennsylvania, USA) and the average roughness values (Ra) were recorded. In the conditions of this study all the tested materials were abraded by the toothpastes and toothbrushes. Hard bristles tootbrush associated with high RDA tootpaste abraded higher all the materials for filling when compared to hard bristles tootbrush associated with low RDA toothpaste and medium bristles toothbrush associated with low RDA toothpaste. Traditional glassionomer cement was the most affected by abrasion, followed by microhybrid composite resin, flowable composite and compomer.

The purpose of this study was to investigate the surface roughness of one restorative composite material when using the Profine System with Lamineers tips. 3 shades of composite resin were used for testing. 15 discs of composite resin were prepared for each shade; 5 discs received no treatment, while the other 10 were divided in two study groups which were polished using either the diamond or the carbide tips using reciprocating movements. The roughness values (Ra; µm) were assessed using a profilometer and the effect of polishing systems on the surface roughness in each group were statistically analyzed. The surfaces of specimens were observed by scanning electron microscopy. The results indicated that the surface roughness depended on type of Lamineer tip and shade of the composite resin.

The purpose of this study was to compare the clinical effectiveness and patient compliance regarding interceptive orthodontics, between a prefabricated functional appliance (PFA) and an Andersen Activator.The PFA appliance used was the TRAINER System™, a flexible appliance made of non-thermoplastic silicone (soft) or polyurethane (hard). The Andersen Activator is a functional acrylic appliance.The sample consisted in 20 subjects (10 girls,10 boys), mean age 10.5 years with a class II division 1 malocclusion and an overjet > 6mm. The patients were randomly selected for treatment with either PFA or AA. Overjet, overbite and lip seal were recorded before and every 3 months after the start of the treatment. The treatment was considered finished when the overjet reduced < 3mm. No significant differences were found in overjet and overbite reduction or lip seal between the two groups. The Activator caused less discomfort than the Trainer, and seemed to be more acceptable.

The aim of this study was to demonstrate the use of adenosine triphosphate– (ATP–) driven bioluminescence as an innovative tool for the rapid chairside enumeration of oral bacteria (including plaque streptococci) and assessment of oral hygiene and caries risk. The study group included 60 patients with 120 direct coronal restorations with three tipes of restorative materials (resin-modified glass ionomer cement GC Fuji VIII, giomer Beautifill Flow Plus Shofu and composite resin (GC Gradia) from witch we have collected 120 specimens using a luciferase-based assay system(system SURE II). The values of ATP were obtained with System SURE II device and statisticaly analised with Wilcoxon Test. The lowest value was shown for glass ionomer cement GC Fuji VIII, comparing with composite resins, but in time we have seen the increase of ATP for all three restorative materials.

The study presents the experience of Medvarix Clinic in treatment of varicous veins using foam sclerotherapy during 2010 – 2015. It is a retrospective study on five years with 893 patients with varicous veins. Mean age – 47years. There were 532 women and 361 men. CEAP classification: CEAP stage III – 279 cases, CEAP stage IV – 246 cases, CEAP stage V – 201 cases, CEAP stage VI – 167 cases. There were 893 ultrasound guided foam sclerotherapy procedures. 261 cases had associated sclerotherapy for perforating veins of closed varicous ulcer and 161cases had associated sclerotherapy for perforating veins for open varicous ulcer. Complications during procedure: misspunction of saphenous vein per primam with a secondary punction – 39 cases, postinjectional hematoma – 11 cases, local allergic reaction – 9 cases. All treated conservatory. Late complications: minor – hiperpigmentation – 47 cases, local inflammations – 101 cases, superficial tromboflebitis – 10 cases, postinjectional necrosis – 9 cases. Major complications: profound tromboflebitis – 1 case. Ultrasound guided foam sclerotherapy is a safe mode to treat varicous veins with good both functional and aesthetic results.

The purpose of this study was to evaluate the effects of various acrylic structures anchored in the territory of termopolimerizable acrylates or flexible injection at tissue level. The changes induced at the termopolimerizable Meliodent acrylate type, took into account the diminishing of the fluid content, responsible for inflammatory and allergic reactions, and adding a metacrilat methyl maleic anhydride copolymer (M88). There were clinically evaluated the effects of different acrylic structure at the tissue level as well as for the resistance forces. Very good results in terms of inflammatory reactions prevalence were mild to obtain with flexible acrylate for termopolimerizable acrylate type Vertex without content of Cadmium and acrylate type Meliodent with the lowest fluid content and copolymer added. The optimal results in the plan of reducing the inflammatory effect of the tissue was doubled by biomechanical good results for Acrylates flexible termopolimerizable acrylate type for Vertex, and acrylate type fluid content Meliodent with 13, 72 and added copolymer.

An important influence factor is the cooling speed value after the heat treatment. It is important to be chooses the optimal cooling regime because the steel can be laminate at high temperature. Another reason for the monitoring of the cooling speed and the conditions of the cooling regime is the possibility that the steel was heated at high temperature after lamination process, for plastic deformation, to realize metallic sculptures or other components used in industry. For this study we considered three groups of samples of the steel, each group had eight samples. Three different mediums for directing of the cooling process were considered. The characteristics of the plasticity and some mechanical properties of the steel have been modified. Finally, after an experimental program, a statistical model tried to demonstrate that a causal connection between two variables such as: the cooling speed (VR) and tensile elongation (A5) of the samples from steel exists. This work proposes to achieve a statistical model and it studies the possibility to improve the characteristics of the plasticity implicitly other properties of steel used for metal structures.