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The purpose of this study was to evaluate the behavior of four restorative materials in non-carious cervical lesions when subjected to exterior stresses of different magnitude. A plane model reproducing a vestibular and lingual section of the lower canine was created. The finite elements are of a two- dimensional type (2D) - quadrilater. Four restorative materials were used: Vitrebond, Dyract AP, Vitremer, Fuji IX. All materials were considered to be isotropic and elastic. Nodal charges were of 40 degrees to vertical, applied on the vestibular side at h=8.993mm to gingival crest, of increasing magnitudes:20, 40, 60, 80, 100, 120, 140, 160 N. The results of this study showed that after restoration stress values in all the elements are (with minimal differences) similar to those in the healthy tooth; a correct restoration leads to normal functioning of the tooth. It can be considered that particular types of restoring materials should be used in particular lesions to be restored, depending on the location of the lesion and the elastic characteristics of the materials and tooth structure. A correct restoration leads to normal functioning of the tooth.

The development and increase use of the endoscopic techniques in endonasal surgery has encouraged the practice of endoscopic dacryocystorhinostomy as a trustworthy alternative to external dacryocystorhinostomy. The purpose of the present paper is to provide another insight into transnasal endoscopic dacryocystorhinostomy by proposing the fitting, at the end of the intervention, of a conformational stent model with aspiration made out of medical silicone similar to a Montgomery tube.

In this study, newly developed polymeric composites based on poly(3-hydroxybutyrate) (PHB), cellulose fibres (CF) and plasticizer (bis[2-(2-butoxyethoxy)ethyl] adipate) (DBEEA) were subjected both to microorganism’s action in controlled conditions, and to soil’s action by sample burial. The weight loss of PHB based composites at 60 days exposure were determined in comparison with neat PHB. The weight variation for PHB based composites buried in a natural soil at 45 days and 90 days was monitored. DSC-differential scanning calorimetry and SEM -scanning electron microscopy analysis were performed on the tested composites after 90 days of soil burial. It was found that the introduction of cellulose fibres into PHB leads to the increase of biodegradability of composites.

In recent years, the inorganic nanoparticles played an important role in the membrane technology due to their special properties, most notably being the hydrophilicity/hydrophobicity modification of the active surface of the membrane. In this paper, the polymer used for membrane manufacturing was polysulfone (PSf) via phase-inversion method. The composite PSf membranes were prepared by blending zinc oxide (ZnO), titanium dioxide (TiO2) nanoparticles and ZnO/TiO2 nanohybrid with three concentrations. Retention of Congo red dye, distilled water permeability, relative flux and relative flux reduction were tested in order to study the effects of the nanoparticles in the membrane matrix. SEM, EDX, porosity, roughness, contact angle, tensile strength and elongation measurement were conducted in this article, also. Compared with control PSf, ZnO/PSf and TiO2/PSf membranes, the experimental results indicated that the ZnO/TiO2/PSf nanohybrid membrane presents the best overall properties, including permeability, retention, and antifouling ability. ZnO/TiO2/PSf membrane exhibits a percentage increase in permeability of 254% and retention of 64.58 % relative to that of the control PSf membrane.

The seven curcumin derivatives were deposited on palygorskite in order to obtain hybrid materials. The fluorescence emission spectra of the obtained materials show a decrease in fluorescence intensity relative to the respective dyes, due to the environments around the dyestuff molecules created in the host matrices. Absorption studies show the best adsorption on the inorganic matrix, for the compounds with the hydroxyl groups. Correlating fluorescence spectra of hybrid materials with the results for absorption spectra of the dyes adsorbtion on the surface of the clay lead to the conclusion that a high percentage of the adsorbed dye had the effect of fluorescence quenching. Thus, it was confirmed that the fluorescent properties of hybrid materials depend on the interactions established between the fluorescent dyestuff and the inorganic network.

The present paper reports the first attempt to synthesize bicomponent hydrogels based on methacryloyl derivatives of gelatin (GelMA) and mucin (MuMA) with different compositions, with potential as wound dressings. While gelatin is widely investigated and used to fabricate scaffolds and coatings stimulating cell interactions and tissue regeneration, mucin - a macromolecule which covers the wet epithelia - remains yet under exploited as biomaterial. The influence of MuMA content on various parameters such as the affinity for aqueous media, stability in simulated physiologic media and the rheologic behavior was investigated. Also, the preliminary assessment of the drug release potential and biocompatibility were performed. The materials’ water uptake capacity and rheologic behavior depend on the pH value of the incubation media, while their composition influences the drug release capacity and cells-scaffold interactions.

This work presents some of researches performed by the authors on execution of plastic parts required for repair works specific to certain machines and plants. Authors focused especially on the repair and reconditioning of certain assemblies which include various machine parts: special spacers, machine-tools guides and toothed gears. Methods shown herein are very simple, accessible even to small workshop and they do not require special equipment, thereby involving minimal expenses. The use of simple programs allow fast and low-cost execution of parts with an accurately determined geometry.

Prosthetic mesh implants in hernia repair are frequently used based on the fact that lower recurrence rates are detected compared to anatomic repair. In latest years, researchers tried to answer weather there is an ideal mesh material for abdominal hernia repair. The studies tried to compare resistance, bio-tolerance, rates of recurrence and infection of several materials used in alloplasty. The results are far from pointing an unique ideal chemical structure of mesh. In our study, we compared the results of a cohort of 265 patients operated in 2010 and 2011 in our clinic for complicated abdominal incisional hernias. We compared the results of polypropylene mesh vs. polyester. Polypropylene mesh proved significantly better for preventing hernia recurrence and showed a lower shrinkage rate.

Combining technological development in the laparoscopic field alongside the increase of surgeon’s experience in partial nephrectomy, have extended the indications of laparoscopic nephron sparing surgery to more complicated cases, increasing the role of suture materials in obtaining a good collecting system closure and hemostasis, with short warm ischemia time and low postoperative complications rate. Suturing materials are continuously developed combining new and unique designs with novel synthetic materials in order to fulfill surgeon’s exigence.

The aim of the paper is to identify the of optimal plastic type used in obtaining thoraco-lumbar orthoses - used in the treatments of comminutive fracture, of burst fracture type of the vertebrae in the lumbar area. For this purpose, with the help of Finite Element Analysis (FEA), a theoretical study was carried out on the influence of elastic properties of plastics, used in the achieving of lumbar orthoses, on the state of tension and on the local displacements of the bone fragments from the traumatized area under the condition of the movement from the base of extension and flexion. In the study the force of flexion, the force of extension and the elastic modulus of plastic material varied on three levels. The theoretical results obtained were completed with clinical trials carried out on a total of 26 patients who suffer thoraco-lumbar comminutive fracture, burst fractures type, at vertebra T11 and were immobilized in Boston-type plastic orthoses made of: polypropylene (PP), rigid vinyl polychloride (PVC-D) and polytetrafluoroethylene (PTFE). As a result of observations, it was found that the use of an orthesis made from rigid plastic material, although it appears higher stresses in the traumatized zone, the displacements of bone fragments are smaller, the pains is higher in the fractured zone, the angle of kyphosis (LKA) close to the normal value and a better mobility of the spine (ODI indicator).