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The obturators are prostheses used to close palatal defects after maxillectomy, to restore masticatory function and to improve speech, deglutition and esthetics. The most commonly used materials in manufacturing maxillary obturator prosthesis are the acrylic resins. The aim of the paper is to present experimental compression and traction tests in order to determine the material properties of Meliodent® Heat Cure produced by Heraeus Kulzer GmbH Germany. This is a two component heat curing polymer used for manufacturing fixed and removable prosthetic devices. Test results show that the average compressive strength of the samples is 94 MPa, while the average compression modulus for all resin samples tested was calculated at 716 MPa. The average ultimate tensile strength of the samples is 58.72 MPa and the average modulus of elasticity for all resin samples tested was determined to be 4213 MPa.

The loss or absence of an eye creates not only a functional disability, but also an important psychological impact on an individual’s social and professional life. Ocular prostheses are maxillofacial prosthetic devices which are generally custom made to replace a lost eye. Polymethyl methacrylate (PMMA) is the most common material used for manufacturing ocular prostheses. The main component of the ocular prostheses is the artificial iris that needs to be identical to the healthy one. For this reason manufacturing the iris is a challenging task for the maxillofacial anaplastologist. The main procedure used in manufacturing the iris is the manual painting technique which can be time consuming and susceptible to error, mainly regarding the color matching. The subject of this article describes an alternative technique of manufacturing the iris. This technique involves using a digital photographing image of the healthy eye which is edited and printed on photographic paper and it seems to offer good esthetic results being less complicated compared to the conventional manual painting technique. The main deficiency of the method is the color distortion which appears after the iris is embedded in the ocular prosthesis. This is caused by an alteration of the photographic paper during the final polymerization stage of the ocular prosthesis which takes place at high temperature.

Tracheal stenosis is a condition where the trachea narrows or becomes constricted as a result of a laryngotracheal trauma, prolonged tracheal intubation, high tracheostomy or systemic diseases.A possible treatment for tracheal stenosis is tracheal reconstruction with costal cartilage grafts that are implanted into the anterior tracheal wall. In order to secure the graft cartilage to the tracheal sidewalls we can use differnt synthetic resorbable materials, such as polylactic acid and polyglycolic acid, that allow anchoring of the costal cartilage to the tracheal wall. The aim of this paper is to present a fixation device for fixing the cartilage graft on the tracheal side walls. This device is designed using a synthetic resorbable material and allows anchoring of the costal cartilage to the tracheal wall using microscrews made of resorbable material.

In this study, the alkali treatment of sawdust (SD) using different concentration (1%, 3%, 5%, and 7%) of sodium hydroxide (NaOH) was performed. The phases change due to alkali treatment on sawdust particles was examined using Fourier Transform Infrared (FTIR) spectroscopy and Field Emission Scanning Electron Microscopy (FESEM). Result shows that the treatment with 5% NaOH on sawdust particles improved the surface roughness of the filler with 21.1 % diameter reduction. Both treated and untreated sawdust particles were reinforced in HDPE matrix using an extrusion method. For comparison purpose, both treated and untreated high density polyethylene/sawdust composites were tested under static and dynamic loading up to 1100 s-1 using the universal testing machine and the split Hopkinson pressure bar apparatus, respectively. Results indicate that the treated high density polyethylene/sawdust composites with better filler/matrix interlocking characteristic shows better mechanical performances as compared to untreated high density polyethylene/sawdust composites under a wide range of strain rate investigated. Apart from that, the mechanical properties of both treated and untreated polyethylene/sawdust composites also show great dependency on the strain rate applied where yield stress, compression modulus and ultimate compressive strength were steadily increased with increasing strain rate. Unfortunately, the yield strain shows the contrary trend. While for the fractographic analysis under dynamic loading, the untreated composite specimens had undergone a severe catastrophic deformation and damages than that of treated composite specimens.

The oral cavity can be considered a complex biomechanical system. Most researches about oral environment’s biomechanics, related to restorative dentistry, endodontics, orthodontics, prosthodontics and implantology are conducted in vitro. Applying the principles of engineering in dentistry contribute significantly to understand aspects of oral biomechanics. We conducted comparative research by finite element method on mixed prosthetic restorations with metal frame of CoCr and NiCr, subjected to the same experimental occlusal loading to determine what type of metal substrate has a better biomechanical behavior.When applying forces in the frontal region, the area of weakness is, according to carried out analyzes, disto-incisal angle of the lateral incisor and at the application of forces in the lateral region, the most vulnerable is disto-palatal cusp of the second molar. Overall, for the particular case analyzed, it is recommended to make metal-ceramic prosthetic restoration with metal support of CoCr, which is less distorted and strained at the experimental application of masticatory forces, compared with metal-ceramic restoration made of NiCr.

The literature highlights the use of nanoparticles for the treatment of wastewaters containing organic compounds such as hydrocarbons, phenols, etc. The oxidation process of pollutants in wastewater from catalytic cracking was performed on nanostructured catalysts based on Fe, Mn and Fe-Mn mixed. The catalysts were prepared by precipitation-coprecipitation in the presence of anti-caking. Measurements for the determination of particle size distribution were carried out using the method of dynamic light scattering. The oxidation process was conducted in a batch reactor equipped with air bubbling system, in suspension of catalysts at a concentration of 1%, a temperature of 85-90o C, pH 9.2, for a period of 2h, 4h and 6h respectively. The best results were obtained in the presence of Fe - Mn catalyst at 6 hours reaction time. Degree of contaminant removal for this catalyst had maximum values of 72.80% for COD, 77.97% for extractible, 74.4% for phenol, 67.53% for ammonium and 67.57 % for sulfides,. Better behavior of Fe - Mn catalyst in the oxidation reaction was due both to the nature of the catalyst, as to well as the smaller size of this catalyst particles.

The purpose of the study is to assess and compare the effects of different antiseptic mouthrinse solutions on traditional glass-ionomer cements. Thirty samples of three traditional glass-ionomer cements used for base: Ketac Molar Easymix (3M ESPE), for restoration: Fuji IX (GC Corporation) and for sealing: Fuji Triage (GC Corporation) were included into three groups. In group 1, the samples were immersed for 14 days, twice a day one minute each, in Listerine Cool Mint, in group 2 the samples were immersed for 14 days, twice a day one minute each, in Parodontax Extra in group 3, the samples were immersed for 14 days, twice a day one minute each, in Sensodine Cool Mint. In control group the samples were immersed in artificial saliva. Within each group, sub-groups were established according the time of cement ageing (one day,seven days and fourteen days). The samples were analyzed for surface topography using a scanning electron microscope and for chemical composition using EDX detector. The antibacterial mouthrinse solutions Listerine, Parodontax, and Sensodine have an erosive effect on traditional Fuji IX, Ketac Molar and Fuji Triage glass-ionomer cements. The most affected cement by erosive action was Ketac Molar, followed by Fuji IX and Fuji Triage. All three glass-ionomer cements tested in this study proved to be more resistant to erosive action after their ageing.

The aim of study was to evaluate some aspects in the clinical effectiveness of fibre-reinforced composite resin periodontal splints on mobile teeth. Fibres-reinforced composite resin retainers are recommended likewise in the treatment of teeth mobility. The study group was formed by a total of 62 patients, which presented first and second mobility degrees of anterior teeth (436 included teeth into research). 42 patients belonging to the experimental group with periodontal splinting, benefited by Interlig-Angelus glass-fibers and Ribbond-Seattle polyethylene-fibres reinforced composite resin splints (295 splinted teeth and 50 splints). The used composite resin was represented by Vertise™ Flow-Kerr. 20 patients (141 teeth) represented the control group, without splinting. All included patients followed periodic monitoring visits (after a week and at one month, for a period of 6 months), in order to evaluate the detaching degree/adhesive failure of reinforced composite resin splints and the reducing of dental mobility degree. The results of study revealed that between the two types of immobilization splints there was no significant difference in the degree of separation/adhesion failure, in the acceptability or in the patient s comfort. Both types of fiber-reinforced composite resin periodontal splints had beneficial effects in decreasing the degree of dental mobility and it was remarked their aesthetic acceptability, respectively the patient s comfort.

The bile duct system has one intrahepatic and as well extrahepatic distinct components, both subject to large anatomical variability. The left component of the bile duct is much more rarely when compared with than the right side. On the 100 pieces of hepatic corrosion casts, we analysed the confluence modality of II, III and IV segmental ducts, to form the lateral and medial branches, and finally the left hepatic duct. Depending on the confluence modality of these ducts and branches to form the left hepatic duct, we revealed three morphological types. In the majority of cases (Type I - 86% of cases) the confluence of segmental duct II and segmental duct III form the lateral branch and the confluence of lateral and medial branches form the left hepatic duct. In most of these cases, the confluence of segmental ducts II and III (to form the lateral branch), is located on the left side of the lateral portal branches origin branches origin, and the confluence of lateral and medial branches (to form the left hepatic duct) is located at the right of the origin of the medial portal branches. Relations of the intrahepatic biliary ducts system with the portal vein element have major practical importance in liver resection surgery and transplantation.

This research aimed to assess properties of emulsions containing various concentrations of collagen hydrolysate produced from calf skins. The most optimum variant of collagen separation from calf skins was used, developed by these authors. The resulting aqueous collagen hydrolysate was employed to produce oil/water cosmetic emulsions containing from 1 to 8 wt % of hydrolysate. Hydration and sensory properties of the proposed substances were evaluated. Appearance and rubbability of the emulsions and washability of make-up were determined. Emulsions containing collagen hydrolysates were assessed by respondents of two age brackets: 18-35 and 36-55. Stability of the emulsions was appraised using centrifuge and temperature testing. On application of these preparations, the skin was highly moistened, particularly in the older respondent group. Consistency of the emulsions was homogeneous and free from clotting. The work confirmed that part of hides constituting the waste can be a potential source of collagen used as an anti-ageing ingredient of cosmetic emulsions.