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This study has been carried out to investigate a new method to improve metallic implant bioactivity for osseointegration by producing a calcium phosphate (Ca–P) surface layer using an immersion process in the Simulated Body Fluid (SBF) of Polypyrrole (PPy) and Polypyrrole/poly(sodium-4styrensulfonate) (NaPSS) conductive hybrid polymers electrochemically synthesized on Ti6Al7Nb alloy. As formed PPy/Ca-P and PPy/PSS-/Ca-P films were characterized electrochemically by Cyclic Voltammetry (CV), Tafel plots and spectroscopically using FT-IR technique. Also, in vitro cytotoxicity of these new organic/inorganic hybrids films was evaluated by yellow 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay after cultivation in a primary culture of osteoblast cells. The PPy/Ca-P hybrid film showed the best electrochemical stability and the highest value of cell viability.

In this work, two commercial block copolymers namely, styrene–ethylene/butylene–styrene (SEBS) and styrene–butadiene–styrene (SBS) with the same amount of styrene were investigated to enhance the properties of recycled polypropylene (RPP) from post-consumer boxes. The amount of elastomer varied from 10 wt.% to 30 wt.% relative to RPP. The elastomer content influence on structural (MFI, DSC, VICAT, HDT, XRD) and mechanical properties (tensile properties, IZOD impact, hardness) of the RPP/SEBS and RPP/SBS blends was studied. The obtained resuls showed that the addition of both elastomers into recycled polypropylene had a similar effect on modification the RPP properties, but SEBS exhibited a higher increase of elongation at break and IZOD impact than SBS, due to a good compatibility with polymeric matrix.

The present paper aims to assess the quality of materials used in the field of removable dentures namely classic acrylate and crosslinked acrylate with improved polymerization using as template vitamin B12 (cyanocobalamin). A major task is the trajectory of Candida albicans biofilm formation and their adherence to the surface of these materials.

Present requirements of the modern man impose the realization of textile products with an increased comfort that should provide, besides their basic functions, the conditions of easy motion, aesthetic aspect, easy maintenance etc. These requirements are conferred by the textile products containing elastomer. The development of elastomer fibers and filaments based on polyurethanes, as well as the progress in textile mechanical and chemical technologies, offer the possibility to obtain textile products with increased elasticity. Wool-types yarns with different torsion degree (twist factor 72÷128) and elastomer content between 4.5 and 11.5% have been realized. This work studies the influence of torsion degree and the elastomer content on yarn characteristics.

An organic–inorganic conductor’s Polypyrrole(Cl)/Zeolite 4A (PPy(Cl)/Z4A) was successfully synthesized by chemical oxidative polymerization at low and room temperature, using FeCl3 as initiator the reaction and dopant at the same time. After characterization, commodity we methods primarily on the polymerization of pyrrole with different molar ratios of [FeCl3]/[Pyrrole] in an aqueous medium, followed by a series of characterizations for the polymers obtained. The right ratio was used for the preparation of nanocomposites PPy(Cl)/Z4A. After each synthesis, the developed product is characterized by FTIR, SEM-EDX, XRD, electrical conductivity and cyclic voltammetry, in order to confirm the success of the process of synthesis and study their properties to specific applications envisaged.

Dental implantology is a frequently applied method for prosthetic restoration of edentulous dental arches. In the past 50 years it has been evolving most dynamically among other branches of dental sciences. According to several reviews and meta-analysis of literature, it seems that the most predictable phase that influences success rate of dental implants is limited only to the surgical stage of treatment [1]. The long term success of dental implants is highly influenced by their biomechanical behaviour, load transfer and osseous tissue reactions to local mechanical tensions around dental implants [1-3]. This in vitro study was aimed to investigate and locate peak tensions inside the fixating substrate of dental implant intimacy. Three root form dental implants were installed, with 14 mm length and 4.5 mm diameter, in tripodistic alignment in a highly rigid and resistant plastic sheet (Araldit-D) also used for photo-elastic measurements. The dental implants were compressed simultaneously and grouped with linear, vertical forces. The mechanical stress distribution and the displacement field of the fixating substrate were analyzed with Digital Image Correlation method (DIC). This modern, non-contact optical investigational method offers highly accurate measurements with great precision (in order of microns, mainly pixel by pixel) practically eliminating all disadvantages and limitations of the most used, classical, experimental methods [4, 5]. Peak tensions were found at the neck area of this type of dental implants. The thickness of the fixating substrate influenced more the appearance of peak tensions rather than the distance between two dental implants. Tripodistic alignment of dental implants might be reconsidered in areas where bone thickness is limited. Virtual, biomechanical simulations should be used in future for surgical treatment planning.

The aim of this study was to assess the effect of toothbrushing with toothpastes having different relative dentine abrasivity (RDA) and toothbrushes having different bristles hardness on different composite resins, compomers and traditional glassionomer cements by surface roughness evaluation. All the samples were evaluated regarding the surface roughness using roughness checker (Taylor Hobson-Surtronic25, AMETEK Inc., Pennsylvania, USA) and the average roughness values (Ra) were recorded. In the conditions of this study all the tested materials were abraded by the toothpastes and toothbrushes. Hard bristles tootbrush associated with high RDA tootpaste abraded higher all the materials for filling when compared to hard bristles tootbrush associated with low RDA toothpaste and medium bristles toothbrush associated with low RDA toothpaste. Traditional glassionomer cement was the most affected by abrasion, followed by microhybrid composite resin, flowable composite and compomer.

The purpose of this study was to investigate the surface roughness of one restorative composite material when using the Profine System with Lamineers tips. 3 shades of composite resin were used for testing. 15 discs of composite resin were prepared for each shade; 5 discs received no treatment, while the other 10 were divided in two study groups which were polished using either the diamond or the carbide tips using reciprocating movements. The roughness values (Ra; µm) were assessed using a profilometer and the effect of polishing systems on the surface roughness in each group were statistically analyzed. The surfaces of specimens were observed by scanning electron microscopy. The results indicated that the surface roughness depended on type of Lamineer tip and shade of the composite resin.

The purpose of this study was to compare the clinical effectiveness and patient compliance regarding interceptive orthodontics, between a prefabricated functional appliance (PFA) and an Andersen Activator.The PFA appliance used was the TRAINER System™, a flexible appliance made of non-thermoplastic silicone (soft) or polyurethane (hard). The Andersen Activator is a functional acrylic appliance.The sample consisted in 20 subjects (10 girls,10 boys), mean age 10.5 years with a class II division 1 malocclusion and an overjet > 6mm. The patients were randomly selected for treatment with either PFA or AA. Overjet, overbite and lip seal were recorded before and every 3 months after the start of the treatment. The treatment was considered finished when the overjet reduced < 3mm. No significant differences were found in overjet and overbite reduction or lip seal between the two groups. The Activator caused less discomfort than the Trainer, and seemed to be more acceptable.

The aim of this study was to demonstrate the use of adenosine triphosphate– (ATP–) driven bioluminescence as an innovative tool for the rapid chairside enumeration of oral bacteria (including plaque streptococci) and assessment of oral hygiene and caries risk. The study group included 60 patients with 120 direct coronal restorations with three tipes of restorative materials (resin-modified glass ionomer cement GC Fuji VIII, giomer Beautifill Flow Plus Shofu and composite resin (GC Gradia) from witch we have collected 120 specimens using a luciferase-based assay system(system SURE II). The values of ATP were obtained with System SURE II device and statisticaly analised with Wilcoxon Test. The lowest value was shown for glass ionomer cement GC Fuji VIII, comparing with composite resins, but in time we have seen the increase of ATP for all three restorative materials.