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The fixed mixed prosthetic restorations (FMPRs) are often manufactured in dentistry. Fixed prosthetic restorations mixed (RPFM) are often used in dentistry. The aim of the study was the presentation of the deficiency and the differences arising between FMPRs with metallic framework plated with two types of dental resins, currently used frequently in Romania, Superpont C + B (Spofadental, Czech Republic) and Royaldent (Palatine Foggyart, Hungary). We have achieved at 102 patients, 132 FMPRs coated with Superpont C+B and Royaldent resins. Patients were divided into two equal groups according to dental polymer used for coating. Long-term study was conducted by biannual monitoring, over three years. The results of the study showed that both resins degrades over time, from the point of view of their physical appearance and their aesthetics, and induced the apparition of gingival inflammation, but restorations coated with Royaldent resin showed less irritation of the gingival tissues.

The paper presents the experiments performed in the laboratory and the results obtained on friction and wear behaviour of the composite materials for the manufacture of brake shoes used for driving and towed rolling stock. The tribological research of these samples made of composite material with organic components aimed to determine the influence of certain material factors and operating regime parameters on the tribological properties of the tested samples. The brake shoes made of composite materials oneusesto replace the conventional cast iron brake shoes, to reduce the noise. The future research will focus on finding composite materials with superior properties compared to the currently used ones, and lower costs.

This paper analyses the influence of processing temperatures of acrylonitrile butadiene styrene (ABS), polyamide 6.6 (PA 6.6) and polyoxymethylene (POM) on some electrical properties when injecting items used in the automotive industry. The ABS specimens were made at the following injection temperatures: 220, 230, 240 and 250°C. The PA 6.6 specimens were made at the following injection temperatures: 280, 290, 300, 310 and 320°C. The POM specimens were made at the following injection temperatures: 180, 190, 200, and 210°C. The determination of electrical properties were carried out using the methods for determining the relative permittivity and the dielectric dissipation factor using zero method with Schering bridge. It was found in the three polymers analysed that the temperature rise processing by injection leads to insignificant changes in relative permittivity (er) and dielectric dissipation factor (tgd).

Testing of fire safety is based on the premise that a band should not be a fire, it would be hard to ignite and if was ignited by an external source of fire should not flame retardant. While fire resistance specifications vary from country to country, formulated to meet any fire performance specifications in the world. Tests on conveyors to assess their compliance with fire safety standards are: Drum friction test: The danger associated with a stalled belt and a driven rotating drum or pulley resulting in frictional heat build up. Laboratory flame test: The possibility of igniting the considerable mass of a conveyor belt with a relatively small ignition source. Gallery fire test: The possibility of a belt, ignited from a larger ignition source, spreading the fire to other areas (often referred to as fire propagation). Electrical resistance test: The possible build-up and subsequent discharge of static electrical charge on moving conveyors.

In this research, the impact behavior of hybrid composite materials subjected to low-velocity impact using the drop-weight installation was investigated. For this study were manufactured eight hybrid materials. All the materials were tested to 90J impact energy. The effect of fabric types used in outer layers on impact performance was studied. The impact characteristics of hybrid materials with G1 glass fabric sheets were compared with those of hybrid materials with G2 glass fabric sheets. The damage surfaces of hybrid laminates were examined by visual investigation. The results obtained showed that the using of G2 glass fabric in structure of hybrid materials improved considerable the impact characteristics.

Our study aimed to identify inorganic elements and bacterial load on the inner surface of the CPAP masks and tubing using scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) and microbiological surface analysis. By SEM were identified structures similar to Staphylococcus and Candida types. When completed by EDX were identified Cl, K, Ca, O, Ti, Na, Mg, Al, Si, S, Cl. Microbiological analysis identified Staphylococcus epidermidis (5000 CFU/mL), Staphylococcus hominis (8600 CFU/mL), and Staphylococcus haemolyticus (6500 CFU/mL). The presence of microbiological and inorganic structures raises concerns on the risk of their inhalation into the airways.

Introducing polymer ligating clips (PLC) or Hem-o-lok clips was a useful alternative to titanium clips in order to perform a safe, efficient and rapid ligation of the vascular structures during laparoscopic and/or conventional surgical procedures. In urologic surgery they are useful during ablative laparoscopic surgery for renal tumor, urothelial tumors, non-functional kidney, bladder tumors and prostate tumors. Polymers’ properties depend on the structure of molecules and vary from flexible substances to expandable rigid materials. They have a high resistance to shock, considerable abrasion resistance and precise durability. Polymers can easily take the desired shape, due to different processing modes. They also have the property of resistance to sustainable action of external forces. The aim of this paper is to evaluate the efficacy and safety of PLC used during renal pedicle ligation in retroperitoneal laparoscopic nephrectomy for renal tumors, high urothelial tumors and nonfunctional kidney.

The purpose of this experimental study is to present the design and biomechanical characteristics of bipolar polyethylene radial head prostheses type KPS (CHM â Poland), as well as to evaluate their use in comminuted fractures type Mason III associated with ligament injuries. We retrospectively evaluated 7 patients with 7 complex radial head fractures with an average age of 38.5 years. The prostheses were implanted through a lateral Kocher approach and patients immediately began the rehabilitation of the elbow. The functional results according to the MEPS score (Mayo Elbow Performance Score) were excellent in 3 cases and good in 4 cases, without stem loosening or residual instability of the elbow. Due to the overwhelming advantages of this bipolar prosthesis (better joint tracking and easier implantation technique) and its very good functional results, the authors recommend this type of arthroplasty in posttraumatic elbow instability.

Polyartetrtys nodosa (PAN) was diagnosed histologically in a dog 14 months old, that presented in the necropsy a hemorrhagic diathesis. The specific lesions were present in the muscular arteries of middle and small caliber and in the arterioles from heart. The modifications are segmentail, chronic, evolving from fibrinoid necrosis to the polyphasic, transmural, neutrophilic, leucocytodastic, macrophagic, lympho-plasmodtic and finally fibrotic vasculitis. The elastolisis predisposes to micro-aneurisms and micro-hemorrhages. Unlikethe perivascularitis, the inflammatory processis extended to the surrounding tissues.

Sleep apnea episodes represent a problem both for the patients and for the patient’s bed partners. The objective of this study was to record the comparative effects of two types of polymeric appliances in the therapy of some mild apnea symptoms (bruxism and snoring). The effect of therapy with the used appliances was pursued on 42 patients, divided in two groups. In the first group of 21 patients, we used a custom made appliance achieved by Erkoflex disks, and in the second group of 21 patients, the preformed SomnoFit®-Oscimed polymeric appliance. The survey lasted for a 12 month period, 1 month before the insertion in mouth of the appliances and 11 months therapy with polymeric appliances. The authors’ questionnaire was completed daily by the patients and their bed partners, which noted the night comfort with inserted appliances in the mouth, the existence/absence of morning pain in the area of the masseter muscle, existence/absence of the morning fatigue, respectively the maintaining, diminishing and the absence of snoring and of nocturnal bruxism. The results of the study were favorable and proved that the nocturnal therapy of bruxism and of snoring, by using these two polymeric appliances were efficient. SomnoFit® appliance performed better in reducing bruxism and snoring, but custom made Erkoflex appliances presented a greater resistance in time.