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The study compares flexural strength of single polymer polyester composites. Composites under examination had the form of laminates differing in the content of the reinforcement phase and the type of material subject to simulated absorption of distilled water and sea water. Simulation tests of distilled water and sea water absorption for single polymer polyester composites with 5% to 20% reinforcing phase were made in accordance with the PN-EN ISO 62:2008 standard. The determination of the measure of degradation of the composites, the magnitude of the bending stress, was conducted in accordance with the PN-EN ISO:178 standard. This work is part of a research relating to the quality and recycling of single polymer composite materials. The testing part of the research is aimed to define the properties of examined materials before they are used commercially in specific products.

Preparation epoxy based hybrid composites were involved kaolin geopolymer filler, organo-montmorillonite at 3phr by using high speed mechanical stirrer. A mechanical behaviour of neat epoxy, epoxy/organo-montmorillonite and its hybrid composites containing 1-8phr kaolin geopolymer filler was studied upon cyclic deformation (three-point flexion mode) as the temperature is varies. The analysis was determined by dynamic mechanical analysis (DMA) at frequency of 1.0Hz. The results then expressed in storage modulus (E’), loss modulus (E”) and damping factor (tan d) as function of temperature from 40 oC to 130oC. Overall results indicated that E’, E’’ and Tg increased considerably by incorporating optimum 1phr kaolin geopolymer in epoxy organo-montmorillonite hybrid composites.

A post-mortem examination of an 1,5 years old Shar- Peis, dog was performed in order to find out the death cause. The macroscopically examination revealed a large amount of blood in the abdominal (hemoperitoneum) The liver was sampled for histopathological examination. Hematoxylin-eosin–methylene blue staining wasperformed in order to prepare the samples for microscopical examination. Based on the specific histopathological changes and taking into account all the pathological data, the diagnosis was liver amiloidosis.

The current trend in screening against cervical cancer is to improve the sensitivity of screening method and p16/Ki-67 dual-stained cytology, represents a promising approach. We performed a study to investigate the correlation between the p16/Ki-67 co-expression and HPV type on a group of patients with ASCUS and LSIL on Pap smear. On all patients, dual stain test and HPV genotyping were performed. In the group of patients with positive dual stain p16/ki-67 test, the number of patients with HPV type 16 was significantly higher than the number of patients with any other type of HPV. Also, all patients with CIN3 or above (cervical cancer) were positive for p16/Ki-67. Our study shows the potential use of those two tests to identify patients with high risk for severe dysplasia.

Postoperative edema and lean body mass may contribute to functional outcome in frailty hip fracture patients. Advances in body mass determination have produced consistent results with A-mode ultrasound. We therefore aimed to determine the utility of A-mode ultrasound in analyzing postoperative limb edema in patients receiving treatment for proximal femur fractures. 4 males and 6 females, with an average age of 74.3 years were included. 4 had fractures of the femoral neck treated by hemiarthroplasty and the rest had extracapsular fractures which were stabilized with short intramedullary nails. Measurements were done using a commercially available A-mode 2.5MHz transducer on the thighs approximately 15 cm proximal to the patella. Comparison showed significant difference between the operated and contralateral thigh circumference (P=0.001) as well as muscle layer thickness differences between femoral neck patients and those with fractures of the trochanteric region (P=0.016). There was no correlation between the A-mode ultrasound determined superficial layer difference and entire layer difference (R2=0.037; P=0.59). However, there was linear correlation between the A-mode ultrasound determined entire layer difference and limb circumference difference, (R2=0.414; P=0.044). Postoperative thigh edema is present in all surgically treated patients for proximal femur fractures. A-mode ultrasound might be a reliable tool to examine adipose and muscle layers separately in the immediate postoperative period. There may be a difference in edema distribution between femoral neck and peritrochanteric fractures but larger samples are required.

The teeth are found in the alveolar processes of both the upper and lower jaw and they form the two maxillary and mandibular dental arches, the various relations of which support the performance of the dental apparatus functions, one of the most important of which is mastication. These relations are also known as interocclusal relations, among which the moments in which the dento-dental contacts (occlusal relations) play an important role. Maximum intercuspation (MI) is the most frequent mandibulo-cranial functional position with dento-dental contact. The vast majority of functional food incision and mastication cycles end in MI. The highest number of dento-dental contacts, and the largest possible stability and surface of these contacts are also achieved in MI. Given the relative easiness of determination, recording and transfer of the MI position, it is used in many clinical situations to report the models of the two arches. The interocclusal recording materials used in our study were seven silicones, six of which with addition reaction, five with special destination for interocclusal relation determination and a putty-like silicone normally used for dental arch impression – Elite HD and one condensation silicone used for impressions. The reason for choosing the last two materials was the fact that some practitioners frequently use putty-like impression silicone to determine interocclusal relations. According to the findings of the measurements shown in table 1, further to the initial impression process, at the time T0, satisfactory results were obtained both for addition silicones and for condensation silicones, Registrado X-tra being the only recording material which exhibited major deviation from the standard dimension (3 mm). As for the Optosil condensation silicone, we noted a significant increase of the thickness of the material starting with the first hour after impression and reaching considerable values on the 5th day, which were 0.3 mm higher than the standard value. Rigid addition silicones have the lowest dimensional stability; putty-like silicones are frequently used to record interocclusal relations for fixed prosthetics, which is wrong since they grow rapidly and this impedes on the space between the treated tooth and the opposite tooth, the result being a high restoration, which may determine premature contacts. Except for Optosil, which exhibited a continuous increase, most materials may be used to mount models in the simulator after 24 h.

The liver segmentation is mainly determined by the intraparenchymatous distribution of the vascular and ductal hepatic elements; from this, the hepatic portal vein (HPV), is the most important afferent element. The lateral branches (LBrs) are serving left lateral division (LLD) of the liver and present a moderate morphological variability. On a total of 160 pieces of liver corrosion casts, one examined the intraparenchymal distribution of portal LBrs and the segmentation of LLD. Regarding the intraparenchymal distribution of the portal branches in the LLD of the liver, we showed two distinct morphological types: Type I (89.375% of cases) in which from the ombilical part of the left branch arise two LBrs; Type II (10.25% of cases) in which from the ombilical part of the left branch arise three LBrs. Knowledge of these morphological types of portal LBrs is important for clinical and surgical practice.

The paper presents the results of rheological tests for three commercial acrylic bone cements currently used in total hip replacement . Moreover, twelve experimental formulations of acrylic bone cements were realized, by partially replacing the methyl methacrylate (MMA) from the classical liquid monomer phase with a new monomer and their rheological properties were evaluated and compared with the commercial bone cements. Thus, the efficacy of acrylic bone cements as anchoring materials as well as their handling and curing properties were estimated. The new formulations exhibited higher elasticity, lower dynamic moduli and clear shear-thinning behavior proving to be potential replacements for classical acrylic based bone cements.

Orthodontic therapy using aligners is a modern treatment option among adult patients. In order to have an optimal control of the orthodontic resuslts, there is a need for knowing the deformation values that can appear in each type of aligner, the optimal thickness values of the appliances and the needed number of aligners for each case. The deformation values for a 0.2 mm repositioned lower central incisor were measured with the use of some strain gauges applied at this level, after a manual set-up was manufactured. Different orthodontic forces were applied on each aligner in order to compare the deformation value during the dental correction. The thickness values of the aligners that were used for this study were 0.625 mm, 0.75 mm and 1 mm. The 0.625 mm aligner had the lowest deformation value dueto a high elasticity of the material.

The aims of the study were to characterise the resin-resin interface when a universal bonding agent (UBA) was used in two different strategies in direct composite repair and to evaluate the bonding capacity of UBA by microleakage assessment. In study groups a micro-filled hybrid and a nano-filled hybrid composite resins were aged in order to simulate an old restorations. As a repair material was chosen the same micro-filled hybrid composite resin that was used as an old restoration. UBA was applied in etch-and-rinse and self-etch strategies and was used as an intermediate layer in repair procedure. After the repair the samples were aged again. In control groups were included non-aged, repaired composite resins samples. The resin-resin interface was characterised on SEM images and the microleakage at the interface was evaluated by dye penetration assessment. Universal bonding agent used in direct composite resins repair showed a very good adaptation to non-aged micro-filled hybrid and nano-filled hybrid composite resins. Aging by saliva storage of repaired composite resins leaded to an enlargement of resin-resin junction and a increased microleakage irrespective of the strategy (etch-and-rinse or self -etch) used for bonding agent application. Etch-and-rinse strategy for universal bonging agent application determined a better interface bonding when compared to self –etch strategy.