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The aim of the study was to evaluate and to compare the interface and marginal leakage of dental composite resins using confocal laser scanning biological microscopy (CM). Ten class II cavities were prepared on the proximal surfaces of 10 extracted teeth, previously kept in 10% formalin to preserve the bonding properties of the tooth structures. Cavities were restored with dental composite resin using the ‘open sandwich’ technique and then assessed using CM. Open marginal adaptations at the interfaces inside the composite resins were identified. The results obtained with CM helped to eliminate and reduce the background information collected from a distance from the focal plane and allowed for the acquisition of serial optical sections from thick tooth specimens. In vitro assessments were thus made using CM on the teeth structure, regarding the occurrence of potential micro-leakages at the restoration interface.

The Czech Armed Forces´ soldiers of all specializations and mainly the chemical corps´specialist are prepared for task fulfillment in military and non-military operations within those a real threat of weapons of mass destruction employment and, occasionally, the real danger of toxic industrial materials leakage is present. They can solve problems caused by acids leakage in contaminated areas mainly during task fulfillment in non-military operations on the Czech Republic territory in cooperation with Fire Rescue Brigades´ chemical specialists. Individual protective equipment which is established in the Czech Armed Forces were neither design for this purpose and, moreover, nor tested and thus there is no real data concerning their chemical resistivity. In recent time, some methods have been introduced into the Czech Armed Forces environment. They are useful for determination of chemical resistivity of barrier materials against toxic compounds detectable with acid-basic (colorimetric) methods and conductometric ones. The paper deals with the possibility of using the presented methods and compares the suitability of their application in relation to the protective garments designated for the Czech Armed Forces members´ body surface.

Novel materials belonging to the class of anionic clays are synthesized by investigating their properties at nano scale. Thus, hydrotalcites or layered double hydroxides (LDHs) were used as drug delivery carriers in order to prevent or to treat infections produced by some pathogen agents. Their physical and chemical properties allow them to include different molecules in the interlayer space and then to ensure their transport to the target. The current work reveals the obtaining of nanohybrid compounds type amoxicillin/clavulanic acid-layered double hydroxides (Amox/CA-LDHs) followed by structural and morphological characterization of these nanostructures for future applications as drug controlled release systems. IR spectroscopy and Scanning Electron Microscopy pointed out LDHs ability to incorporate the medicines without modification of therapeutic activity.

The aim of the present paper is to give an up-to date on computer aided design and manufacturing (CAD/CAM) additive techniques and synthetic polymers for bone reconstruction in the maxillofacial region. Additive manufacturing represents a promising field for future research in bone replacement/regeneration. However, standard guidelines for mimicking clinical environment with the different bone characteristics are strongly required. The rapid prototyping techniques, particularly, bioprinting allows the construct of 3D living functional tissues able to replace, in the near future, large defects caused by tumor excision, trauma, clefts or infections, limiting the autogenous bone graft requirement.

Proper positioning of premature babies resulting from different maternal chronic conditions before pregnancy and hypertension induced during pregnancy can promote normal balanced development with maximizing the sleeping conditions and minimizing the gastric reflux. We conducted a retrospective study on data from Bega Clinics – Obstetrics and Gynecology and Neonatology for 2012-2013 about premature babies of mothers with pathologic pregnancies. Part of the newborns was positioned in a flexible polyurethane foam cocoon and clinical observations on sleeping states and the presence of gastric reflux were noted. In our study, 453 (10.5%) cases of women with different pathological conditions out of 4,312 cases were encountered. Most of them (48%) had a diagnosis of chronic hypertension, followed by chronic renal diseases (34%). Hypertension developed during pregnancy for both years, happened in 340 (7.88%) cases. Severe forms of hypertension were noted in 57.05% of them. Incidence of preterm birth babies was 11.22% (484 cases), of which 12 cases (8.67%) resulted from pregnancies with different forms of hypertension. Clinical observations stated that sleeping quietly and awake and quiet have increased the most when compared with babies positioned in the cocoon (44 babies) compared with babies (45) out of cocoons. Only 8 (18.2%) babies positioned in the cocoon experienced gastric reflux comparatively with 41 babies that were positioned in regular conditions.

Acrylic resins based on polymetyl metacrylate are used in dental prosthetics as base for dentures. One of the major failure causes of dentures is the fatigue damage of the acrylic resins. These materials, in addition to mechanical behavior, also present a high risk of structural defects (voids, micro-cracks, residual monomer) that can significantly affect the fatigue behavior. In this paper, two commercial acrylic resins have been experimentally analyzed in terms of mechanical and fatigue behavior. Tensile constant amplitude fatigue tests with stress ratio R = 0 and frequency of 2 Hz have been carried out on samples of the two acrylic resins, prepared according to the manufacturer’s recommendations. The results revealed, besides the brittle fracture character, a similar fatigue behavior following a Weibull distribution. Also, through statistical processing of the results, the fatigue curve equations of the two analyzed materials were estimated for different levels of confidence.

Our purpose was to study tibial plateau fractures considering the rise of their incidence, their potential immediate seriousness or late complications and their complexity. We realized a clinical-statistical study concerning the incidence of tibial plateau fractures taking in account critaeria like age, sex, mechanism of injury, fracture type and correlations between these. The study involves 126 patients, 98 (77.77%) being treated surgically and 28 (22.22%) conservatory between 2008–2016 in the I-st Clinic of Orthopaedics and Traumatology Timisoara. Approximately 2/3 of cases are of Schatzker type I, II and III. Type VI Schatzker occured in 5.78% of all, the mechanism of injury being split almost equal between road accidents and falls from height. Road accidents prevale as a causing circumstance of tibial plateau fractures. 2/3 of the tibial plateau fractures associate with other significant regional lesions. Bone lesions are not rarely underestimated by plain radiographs. Therefore evacuation of haemarthrosis (showing lipohaemarthrosis) and high performance imaging (CT, MRI) are often needed. In comparison to other fracture sites, imperfect reduction of tibial plateau fractures results more frequently in long term sequellae. Being frequently complex, comminuted fractures with associated regional lesions tibial plateau fractures raise the complexity of the medical act from establishing a complete diagnosis to the final therapeutic measures. For a correct and complete preoperatory diagnosis frequently high performance imaging is needed. Tibial plateau fractures significantly affect patients, the healthcare and social-economic system, the healing and rehabilitation.

This article reports an environmental study concerning the liquid detergent contamination and its impact on some plantlets, e.g. Phaseolus vulgaris and Petroselinum crispum. In this context, this study focuses on specific modifications of the physical-chemical and biochemical characteristics of some plantlets induced by liquid detergents present in the soil, both bio-based and without environmental compatibility. The results of this study showed that a decrease (over 60%) in total chlorophyll per fresh weight could be solely due to the presence of non-biodegradable liquid detergents in soil, in various concentrations: 0.125%, 0.25% and 0.5% (wt/wt), calculated on water mass. On the other hand, the action of the detergents on the plantlets has revealed a decrease in the catalase activity in the case of both types of detergents.

Compressive strength of the polymeric composites is an important data for design of composite structures and therefore a depth study of this mechanical property is imperative. The mechanical properties of the polymer composites vary in the very large ranges according to the characteristics of the constituents, to their proportions and many other factors. Compressive property and failure mechanism of polymer composite materials reinforced with glass fiber were investigated in this paper. The experimental data for the studied materials were included the compressive strength, strain, poisson’s ratio and modulus. Some of these experimental values could be affected by aberrant errors. This paper also presents an application that removes the experimental data affected by gross errors from the sample of numerical values. The elimination of experimental data affected by gross errors is based on Chauvenet criterion.

The aim of this study was to evaluate and to compare the surface hardness of three types of resin-based materials used for direct restoration after heating at different temperatures. A giomer (Beautifil II, Shofu Dental), a compomer (Dyract eXtra, Dentsply Sirona) and a hybrid composite resin (Gaenial Posterior, GC Corporation) were selected for this study. Twenty disk-shaped specimens of each material were heated at room temperature (21°C), at 37°C, at 50°C and at 60°C. Vickers microhardness test was performed on top and bottom surfaces using digital microhardness tester (Micro-Vickers Hardness System CV- 400DMTM, CV Instruments Namicon). The top and bottom surfaces VHN was calculated as a mean value of five determinations. Also, the microhardness ratio was calculated by dividing the top mean VHN value by bottom mean VHN value. Increased mean hardness values were recorded after heating, irrespective of resin-based tested materials. The highest hardness values were recorded after heating all three materials at 60°C, followed by the hardness recorded at 50°C, 37°C and 21°C. For top surfaces, the lowest hardness value was recorded in Dyract eXtra group when samples were warmed at room temperature and the highest hardness value was obtained in Beautifil II group when samples where heated at 60°C. For the bottom surfaces, Dyract eXtra specimens heated at 21°C presented the lowest hardness values and Beautifil II samples heated at 60°C presented the highest hardness values. On top and on bottom surfaces Dyract eXtra showed the lowest hardness values, followed by G-aenial Posterior and Beautifil II, irrespective the heating temperature.