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The research carried out within this paper addresses the issue of impact analysis with a spherical ball of an automobile fender, following two directions: the finite element method modeling of named part and situation, and experimental validation of the study mentioned beforehand. The part itself – car fender – is represented by a thermoset composite panel armed with Kevlar-Carbon fibers, while the analyzed situation is depicted as a Charpy/Izod test with a spherical ball on the specified component. The evaluation of named inquiry is performed in a virtual environment by means of FEA and verified accordingly within laboratory testing.

Dental sealants are important components of preventive dentistry. The aim of this clinical trial was to compare the effectiveness of an unfilled resin-based sealant and a carbomer-based dental sealant. 42 child patients with completely erupted inferior first molars and with diagnosed bruxism were included in the study. At 2 weeks, respectively 6, 12 and 18 months were evaluated the effectiveness of sealants after marginal deterioration, retention and the presence of caries. The results of the trial showed that unfilled resin-based sealant presented fewer modifications.

The work focuses some experimental aspects concerning the weight gain, differential scanning calorimetric (DSC), dilatometer analysis (DIL) and thermo - gravimetric analysis (TG/DTA) for a composite material, based on cotton tissue and unsaturated polyester resin noted MCTDBN and immersed in salt water with 5% NaCl for 90 days. Following these analyzes are emphasized the thermal expansion, temperature glass transition and thermal decomposition. Before of thermal analysis, the treated specimens were dried in an oven at temperature of 30°C for several days. The paper presents also the effect of salt solution treatment and comparative analysis between untreated and treated composites.

The aim of our study was to evaluate the deformation resistance of two palatal plate type connectors of removable partial dentures and to make a comparison between the reduced palatal plates and the large ones, in terms of bending resistance during function. We tested 10 maxillary class I Kennedy removable partial dentures made for real clinical cases and duplicated their connectors, 5 of each type. A Universal Loading Machine was used to apply a bilateral progressive force to the PM2-M1 area until the samples bended, recording the force value at which the first change occurred. The results were analyzed using the ANOVA method. For the reduced palatal plate group, the minimum bending force value was 1584 N, the maximum bending force value being 2920 N. For the large palatal plate group, the minimum bending force value was 3150 N, the maximum value being 3380 N. Statistical analysis of data using the ANOVA method shows that the results are statistically relevant, with a p value of 0,001031 (p[0,05). The results showed that decreasing the width of the palatal plate can have a significant effect on the deformation resistance of the major connector and can affect its rigidity; in clinical practice, these results can help dentists to use alternative appropriate design methods of increasing the rigidity of reduced palatal plates, in order to protect both the remaining structures and the acrylic components of the dentures during the years of its functioning.

Aortic valvulopathies, and especially aortic stenosis (AS), are the most common valvular disorders. Untreated, 50% of patients with severe AS will die within 2-3 years from the onset of symptomatology. The standard treatment consists in the surgical replacement of the aortic valve with mechanical or biological prosthesis. 40 patients were included in the study after replacement of the aortic valve with double disc mechanical prosthesis for severe degenerative AS. The disks of the prosthesis are made of pyrolytic carbon characterized by extreme hardness, which provides wear protection over the years. The ring is composed of a graphite substrate coated with pyrolytic carbon and attached to a suture collar made of polyethylene (polytetrafluoroethylene - PTFE) or polyester (Dacron® or Teflon®). This study evaluates mass regression and left ventricular mass index at three months and one year postoperatively. The regression of the left ventricular mass at 3 months after the surgery is 25.86%, and at one year after the surgery this regression was reduced - 15.11%. The regression of the mass of the left ventricle and especially the premature regression, correlated with the degree of hypertrophy of the left ventricle preoperatively, highlight the beneficial effect of the double disc mechanical prosthesis.

The current paper presents the advantages and disadvantages of the polypropylene mesh used for patients who underwent abdominoplasty associated with the treatment of abdominal wall defects. The study was based on data obtained from 64 patients who benefited from abdominoplasty associated with the surgical treatment of abdominal parietal defects, such as: hernias, eventrations and diastasis. The results of the research show that the use of the polypropylene mesh is associated with an increased resistance of the rectus abdominis sheath plication, the reduction of the postoperative complications rate and the improvement of the patients’ satisfaction regarding the aesthetic result of the surgical intervention.

Objective of this study was to develop and validate HPLC-UV method for detection of LTG in lipid nanoformulations. HPLC-UV method was developed according to ICH Q2(R1) guidelines. Central composite design was used effectively to optimize and study the effect of buffer strength, flow rate, pH of buffer and mobile phase composition on responses such as tailing factor, peak area, retention time and number of theoretical plates. The 30 mM ammonium formate buffer and acetonitrile (in the ratio 65:35 %v/v) was used as mobile phase in the study. The mobile phase was delivered at the flow rate of 1.0 mL/min. The detection of buffer was performed at 256 nm using UV detector. The drug entrapment of prepared formulation was also determined using developed HPLC method. Retention time of lamotrigine was found to be 3.844 min. The coefficient of determination (r2) value from linearity was found to be 0.9982. Percent relative standard deviation value of precision was found to be within the acceptable range. The estimated LOD and LOQ were found to be 9.07 ng/mL and 27.48 ng/mL, respectively. Drug entrapment of prepared lipid nanoformulation was found to be 73.44 ± 6.65%. The results conclude that the developed analytical method is simple, precise, sensitive, fast and reproducible. Applications of developed method for determination of drug entrapment in prepared lipid nanoformulation confirmed that the developed analytical method is suitable for estimation of lamotrigine in lipid nanoformulations.

The main purpose of this study is to evaluate three different adhesiveprotocols between two composites. We used 60 composite specimens (Kerr’s Herculite XRV Ultra), randomly divided into 3 equal experimental groups, in which adhesion was performed using different protocols: Group 1 (n= 20) surface preparation with a 1.4 mm cylindrical diamond bur (Kerr Dental, FG503C-5) + etch and rinse technique in 2 steps; Group 2 (n= 20) surface preparation with a 1.4 mm cylindrical diamond bur (Kerr Dental, FG503C-5) + Al2O3 (Zhermack Dental) sandblasting + etch and rinse technique in 2 steps; Group 3 (n= 20) surface preparation with a 1.4 mm cylindrical diamond bur (Kerr Dental, FG503C-5) + glycine (EMS) sandblasting + etch and rinse technique in 2 steps. Adhesion assessment was made by measuring tensile strength with a universal testing machine, the INSTRON 3343 (Instron®, USA). At the end, the results were statistically compared using the ANOVA test. Group 3 (glycine protocol) had the greatest values in terms of tensile strength.

The wastes from polyethylene terephthalate (PET) packaging can be turned into armatures for concrete used in the transports infrastructure (roads with rigid concrete structure, pedestrian and concrete pavements and borders), as well as in the construction of safety elements (support walls, bulwark foundations). This experimental research was meant to create dispersed reinforced concrete with armatures from polyethylene waste, originated from the recycling programmes of PET–type packaging. The experimental programme was aimed at constructing some samples of dispersed reinforced concrete from recycled material coming from polyethylene terephthalate (PET) packaging wastes, their testing to the compressive strength and the comparison of results with the characteristics of the standardised samples of concrete (class C30/37). All the reinforcements used in this work to consolidate the dispersed reinforced concrete type were made from a mix of polyethylene terephthalate (PET) packages, of different types and characteristics, which are found daily in supermarkets and which then reach waste. The choice of a mix of polyethylene terephthalate (PET) packaging was chosen in order to render the general recycling of these types of materials as good as possible.

This paper is the second part of a study regarding the biomechanical behaviour of mandibular bone in the context of different periodontal splinting systems, occlusal forces and load distributions. Electric resistive tensometry method was used to measure the strains developed in mandibular bone replica. The tests were carried out on six mandibular acrylic models, each with 8 natural teeth. The experimental groups were defined corresponding to the bone condition and splint type: normal height bone; bone resorption without splint; bone resorption and wire-composite splint; bone resorption and polyethylene fiber-reinforced composite splint. Each sample was subjected to three similar loading cycles, the force being applied successively on four incisors, two central incisors and canines, and the specific deformation values were read for four loading forces: 30 N, 50 N, 100 N and 150 N. In case of bone loss, the bone deformations are up to 110%. Periodontal splinting redistribute forces, reducing incisors bone strains associated with a slight increase in canine bone strains.