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The use of Additive Manufacturing methods in the manufacture of custom implants and the development of new biocompatible materials that can be processed by Selective Laser Sintering Technology, represent a trend in biomechanics. In this study two types of biomaterials were analysed and tested – PA 2200, the most used material for cranioplasty, obtained at different laser powers and polymethyl-methacrylate (PMMA). In order to analyse the mechanical behavior of the evaluated materials, the mechanical tests were made for tension, flexure and compression. It was found that the values for PA 2200 material are within the limits of the mechanical characteristics required for cranioplasty implants.

The success of an endodontic material depends on its sealing ability, as most post-treatment endodontic disease usually occur due to marginal leakage in the apical area of the root canal. The aim of our study is to evaluate the sealing ability of a Mineral Trioxide Aggregate-based endodontic sealer (ProRootMTA), compared to other frequently used materials, on extracted human teeth, using a dye penetration leakage test. The results showed a significant difference (p[0.01) between ProRoot MTA and the other two sealers.

The paper presents a method for elaboration and characterization some chitosan-gelatine membranes with different collagen-gelatine mass ratio, cross-linked with glutaraldehyde (GA) and coupled with extract plants. The aqueous extracts obtained from these plants were analyzed in terms of biologically active substances content (amino acids, polyphenols and phytosterols). The investigation for all obtained membranes involves: SEM microscopy, porosity, degradation test, contact angles measurement, hemolisys and antibacterian index determination.

This paper analyses the influence of carbon filler content over the mechanical properties of vinyl ester nanocomposite. The carbon fillers used in this study were graphite and graphene nano sized particles in the following weight percentage: 0.10, 0.15 and 0.20. The mechanical properties such as modulus of elasticity, flexural stress and flexural strain were determined using three point bending tests.A significant enhancement of overall mechanical properties were achieved for some of the nanocomposite materials studied.

This paper deals with an innovative technique regarding the embedding of biliary stones in plastic materials as an alternative and viable solution for increasing their mechanical resistance during processing for preparing the samples for instrumental analysis. The human gallstones provided from a single patient were embedded in two different polymeric plastics. The samples were investigated for their mechanical resistance under surface grinding using a rotating abrasive wheel on a bench grinder, as well lathing on a lathe machine. A discussion for the best method of embedding and the sample preparation is presented.

In this paper we have studied the influence of discontinuities on elastic and mechanical properties of composite materials reinforced with woven Carbon, Carbon-Kevlar and Kevlar. In addition, we have studied the way variations of the volume proportion of reinforcement influences elasticity modulus and tensile strength for the studied composite materials. In order to appreciate the property difference between different areas of the composite material and also the dimensions of the defective areas, a relative uniformity influence coefficient was introduced offering us a tool for assessing the mechanical behaviour of the studied composite compared with a reference composite. We have also performed experimental validations of the obtained theoretical results.

The paper analyses the effect of oxides powder deposition by plasma spraying and remelting with laser beam on the cavitation resistance of Ti-6Al-4V biphasic alloy. The deposited and remelted coatings were tested for cavitation erosion on the magnetostrictive vibratory apparatus with nickel tube. Using optical and scanning electron microscopy, were obtained qualitative informations about the degradation mechanism and the cavitation erosion evaluation was done by comparing the specific erosion curves of Ti-6Al-4V substrate with those of coated layers.

This paper presents the effect of reinforcement for styrene-butadiene and styrene-isoprene block copolymers with bentonite in correlation with morphology biphasic thermoplastic elastomers.

This paper presents the results of the research carried out in order to establish the optimum technology of polypropylene pipes, analysed from the point of view of temperature, time and labour press. Analysing the values obtained in the practical samples, the graphics of variation of components after assembly were traced, decreasing the diameter of the pipe after the assembly, the parameters that define significantly the quality of the assembly. The need to address such themes derived from the fact that in the literature, in the present time there are not sufficient and relevant information with regard to the assembly of pipes and connectors of PPR, most of the information being provided by the manufacturers and they are confined to the indication of the parameters of the assembly process.

In this study, the static and dynamic properties of LLDPE/RH composites, with different filler contents of 5 wt% RH, 10 wt% RH, 15 wt% RH, 20 wt% RH and, 30 wt% RH were studied at different levels of strain rates (0.001/s, 0.01/s, 0.1/s, 650/s, 900/s and 1100/s) using a conventional Universal Testing Machine and Split Hopkinson Pressure Bar apparatus, respectively. Results show that the strength, stiffness and yield behavior of LLDPE/RH composites were strongly affected by both filler content and strain rate loadings. Apart from that, the rate of sensitivity of LLDPE/RH shows sgreat dependency towards applied strain rate, where it was increased with increasing strain rate. Unfortunately, the thermal activation values show contrary trend. Besides, at dynamic loading, the fracture surface analysis of the composites showed that all specimens experienced massive plastic deformation.