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The purpose of this experimental study is to present the design and biomechanical characteristics of mobile bearing postero-stabilised total knee prosthesis type MC2®- C2F® and to evaluate their use in severe primary knee osteoarthritis. The experimental part was carried out on 20 patients who benefited from mobile bearing postero-stabilised total knee prosthesis type MC2® in University Hospital Sf Spiridon Iasi, Romania. From the radiological point of view there were no mechanical complications in a 3 year follow-up. The functional recovery had a good outcome and patients currently have an active flexion between 70° and 110°, with extension between 0° and -15°. No pain was registered in full weight bearing and in active joint movement.The clinical and radiological outcome at 3 year follow-up is satisfactory and the results convinced the authors that this type of prosthesis is a good option in any primary knee osteoarthritis with no significant bone loss.

This in vitro study analyses the biochemical interaction between saliva and three types of dental composite resins (a direct resin, an indirect resin and a dual-cure resin used for cementation of indirect dental restorations). The resin samples were obtained following a specific protocol and in line with the producers’ recommendations; the resin samples were incubated with saliva samples collected from 19 healthy volunteers. The obtained results showed that the tested composite resins did not produce significant changes in oxidative stress parameters that were analysed (albumin, uric acid, GGT / gamma glutamyl transferase, OXSR-1 / oxidative stress responsive kinase 1) and do not influence the inflammatory salivary status reflected by the levels of IL-6 - an inflammatory marker.

The purpose of this study was the synthesis of two types of biodegradable materials with synthetic polymers (PLGA) or natural polymers (collagen) and hydroxyapatite, followed by determination of the encapsulation percentage of the drug in the polymer. Regardless of the chosen method, the percentage of the encapsulated drug was found to be quite high: 15.92% in the Coll-HA-Genta material and 19.59% respectively in the PLGA-Genta biocomposite. The therapeutic value of gentamicin was improved by encapsulating it in delivery systems, contributing to sustained release for a long time (about 30 days).

This paper presents an experimental study to determine the behaviour of composite panels, made of polyurea sprayed on Kevlar or Dyneema support layers, under blast and fragments produced by an improvised explosive device (IED). The fragments used for tests were steel bearing balls of 8 and 10 mm propelled by a plastic explosive charge and bullets cal. 7.62 mm, type Full Metal Jacketed Armor Piercing (FMJ AP) and Hollow Point Boat Tail (HPBT), with impact velocity greater than 500 m/s. To determine the fragments attenuation, their velocities before and after the impact with the composite panel were measured and compared. In order to assess the blast attenuation, the reflected pressures measured by two face-on sensors, one of which was covered by the composite panel, were compared. Also, to explain the behaviour of composite panels under blast, the shock polars of materials in the panel‘s composition were plotted. The results have shown that the composite panels have a low rate of attenuation of fragment velocities but a very good ability to attenuate the pressure and impulse associated with the shock wave.

Hormonal Intrauterine Devices (IUD) were developed based on copper IUD with the role to release a daily amount of hormones. From a structural point of view Levonorgestrel-IUD (L-IUD) is a small T-shaped piece of plastic, which contains levonorgestrel. When compared with the oral route of L-IUD administration, it provides some advantages because it releases levonorgestrel directly into the uterus. Our aims were: (1) to compare the thickness of uterine jonctional zone (UJZ) in two groups of patients with and without inserted L-IUD, (2) to evaluate the changes in thickness of UJZ after the insertion of L-IUD in two patients with adenomyosis, and (3) to obtain and to characterize a similar T-shaped polyurethane (PU) foam used as a levonorgestrel delivery system. On the one hand, the results confirm that L-IUD is effective in thinning the UJZ and in the treatment of adenomyosis, while on the other hand, the characterization of the PU materials (Zetasizer measurements, their thermal degradation, UV-Vis spectra and skin irritation tests) revealed that this polymer can be used as a safety and prolonged levonorgestrel carrier.

Dental caries and secondary caries are the most common problems in dentistry. Many studies provided evidence for the anticariogenic effect of fluorides. The incidence of secondary caries is decreased in teeth restored with fluoride releasing materials. The purpose of the present in vitro study is to evaluate the fluoride release and uptake capability of two glass-ionomer cements and two compomers. A total number of 60 specimens were prepared according to the manufacturer’s instructions using silicone molds. The specimens were transferred in plastic containers containing artificial saliva (pH=7), incubated at 37°C for 24 h and divided in three subgroups: control group, varnish treated group and dentifrice treated group. The fluoride ion content was measured on five times during a period of 30 days using an Orion 720A fluoride meter with 9609 BN fluoride ion electrode. The self-curing glass-ionomer cement released the highest amounts of fluoride ions at the beginning and after the one month study period. The samples of the four materials tested in the varnish treated groups showed significant differences compared to their control groups on the second day. Dentifrice treated groups did not show significant differences compared to their control groups, except values measured after 30 days. Application of fluoride varnish produced an increase of fluoride release for the first 24 h in case of all materials. However, results suggest that the use of fluoridated dentifrice would be more effective in caries prevention due to their fluoride uptake capability.

\Six new products were obtained by deposition of para-tert-butylcalix[4]arene (t-Bu-C4OH), calix[4]arene (C4OH) and tetra-methoxy-calix[4]arene (C4OMe) on two types of SBA-15 mesoporous silica. All the products were characterized through thermogravimetric methods and SEM microscopy. The obtained results confirm the functionalization of the silica materials with the calixarene macrocycles. Considering all the obtained products, the thermal analysis suggests the strongest connectivity to form between the C4OMe systems and mesoporous silica substrate.

Bone fracture fixation uses both consecrated materials, such as metals/metal alloys, as well as synthetic materials. Synthetic materials are extremely versatile in terms of simulating biological structures, biocompatibility and, in some cases, avoid the subsequent interventions for removing the prosthetic material. Fixing an osteoporotic fracture presents major risks of failure due mainly to the bone fragility. To reduce the risk of failure, prosthetic materials have been improved with various cements. The purpose of the current study was to assess the mechanical properties of different orthopedic screws covered with a new polyurethane acrylate polymer (PUA) in order to improve the stability of the screw for the subsequent fixation of the fragility fracture. To test the efficiency of the new polymer, the breaking/fracture strength of the orthopedic screws coated with PUA was evaluated, in comparison with the screws without coating material. Our data shows that tested PUA improves the bond between the screw and bone. We estimate that the effect obtained is caused by the partial damping of the loading force due to the elastic component of the polymer.

Disadvantages of diacrilic composite resins and glass ionomers cements have stimulated research to develop hybrid materials to eliminate the downsides and take advantage of their benefits. The purpose of this study was three-dimensional analysis of a flux material with a resin-modified glass ionomer (RMGI) cement in preventive sealing by two techniques of enamel substrate approach, respectively, with acidic conditioning with 37% orthophosphoric acid and free. The best results were observed in the RMGI when no substrate conditioning was performed.

The composition of electrical wires and cables is of critical importance in controlling fire risks. In this respect, polyvinylchloride (PVC) composites are extensively used. Yet, PVC composites are multiple systems in which the final properties depend on the nature and size of the reinforcement or flame-retardant agent and the type of lubricant used for their preparation. Thereby, in this study two series of PVC composites, with stearic acid and calcium stearate as lubricants were prepared in parallel, and additivated with various commercial minerals as reinforcement/flame retardant agents, such as calcium carbonate, alumina trihydrate (ATH) and HMH (a mineral of hydromagnesite and huntite). Following the structure (by FT-infrared), thermal behavior (thermal analyses and differential scanning calorimetry) and mechanical properties (dynamic mechanical analyses, tensile strength and elongation at break) of PVC composites, the flame-retardant effect of the selected minerals was investigated by measuring the limiting oxygen index (LOI). Only ATH and HMH-based composites presented higher flame-resistance, relative to the control samples, making them suitable for the proposed application. The contact angle was evaluated for determining the hydrophobicity of composites when using ATH or HMH, to get an opinion about the stability of the materials in moist environments. Finally, SEM was used to determine the homogeneity of PVC samples.