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The aim of our study was to investigate the root surface after scaling and root planning (SRP) made with Periotor inserts and contra angle handpiece Profin, comparatively with other two very popular SRP techinques: Gracey curette and ultrasonic piezoelectric scaler with perio-tips. A total number of 30 teeth extracted for periodontal causes were used, 10 teeth for each method of scaling. Samples were examined using ESEM and for each sample micrographs were obtained in four magnifications (× 200 × 1000 × 2000 × 5000). Two examiners blinded to the scaling method but previously trained in evaluating the root surface morphology using RSSL index, examined each micrograph and established a RSSL score. It was considered the highest score for each sample and the average scores were calculated for each group. Lowest scores were obtained by scaling with Periotor inserts followed closely by ultrasonic scaling with perio-tips. Use of Gracey’s curettes left the most extensive areas of dentin denudation and in some samples even traces of scratching. In conclusion, our study highlights that using Periotor inserts for root surface scaling the root surface morphology obtained is the most regular and even with fewest dentin denudation areas.

Polyester-ether polyols were prepared by a clean method, consisting of PET wastes glycolysis with common diols (diethylene glycol and a mixture diethylene gycol/ dipropylene glycol) and a diol derived from biomass (isosorbide) followed by mono-esterification of the glycolyzed products with phthalic anhydride and subsequent propoxylation, under relatively mild conditions. The polyester-ether polyols were characterized by chemical methods, dynamic viscosity measurements, gas chromatography and 1H-MNR spectroscopy. Experiments, conducted in order to test the polyester-ether polyols in rigid polyurethane (PUR) foams formation, showed that the chemical composition of the experimental polyester-ether polyols is fully suitable for reaction with di-isocyanate. The physico-mechanical and flame retardant properties of PUR foams, prepared by using the experimental polyester-ether polyols up to 30% wt. of the polyol component in the foam formulations, were at least similar to the properties of the foam obtained from PET wastes by classical recycling methods. The synthesis method is in agreement with the principles of clean technologies and green chemistry, in the sense that no by-products and no wastes results.

Endoscopic dacryocystorhinostomy (DCR) is a well-established treatment for epiphora caused by anatomic or functional obstruction of the nasolacrimal apparatus. A thorough understanding of the endonasal anatomy, wide marsupialization of the lacrimal sac, and meticulous care for the mucosa are critical for success. Nasal endoscopy has also facilitated the level of performance of the technique. The aim of this paper is to propose a new alternative for the dacryocystorhinostomy (DCR). The use of the new stent with a special design will give the surgeon the ability to keep the stent in the lacrimal duct as long as it is needed.

The aim of this study was the encapsulation of ginger essential oil in polymer particles. The chosen method was suspension polymerization of methyl methacrylate. In all cases, the polymerization process in the presence of ginger essential oil leads to decrease of the conversion at similar reaction intervals. The different reactivity of the essential oil components towards the free radicals generated by the thermal decomposition of AIBN was determined using GC/MS headspace analysis. The amount of encapsulated oil was determined by thermogravimetrical and GC analyses. TGA provided less reliable data about the total encapsulated essential oil. However, the extraction and GC analysis of the samples confirmed a higher content of essential oil in sample 2 (0.03 mol/L AIBN), and the lowest in sample 4 (0.09 mol/L AIBN).

Utilization of relatively simple devices fitted for the ring frames permits the realization of yarns with filamentary elastomer core. The aspect of yarns is similar with that of the classical yarns, but their structure and characteristics are very different. Depending on the core-sheath combination, filaments and fibers nature and characteristics, the quota of components participation, yarn twisting degree etc., the range of these yarns assortment is practically unlimited. Due to the large capacity of deformation and recovery of the elastomer filaments, the classical methodologies used to determine the classical yarns characteristics cannot be applied to the elastomer-containing yarns, and these yarns show specific indicators for characteristics assessment. This work presents a synthesis of some ample researches on the methods and characteristics of wool-type yarns with elastomer core, as well as the transfer of elastomer filament characteristics to the composite yarns that contain elastomer.

When we talk about plastic industry, then one of the most important aspects of this trade is giving the plastic its bright and attractive color. As more and more people crave for the “return to nature” touch, pigments extracted from vegetal materials considered as waste have been analysed for dyeing textiles and manufacturing colorants for painting. Senescent leaves of Vitis vinifera L. have been tested for their capability of extracting organic pigments (chlorophyll, carotenoids, xanthophylls and anthocyans). The results show that the potential exists, further research is needed in order to best develop the methodologies needed.

Virtual-patient (VP) software is an innovative educational tool which provides a safe environment in which students and interns can acquire clinical skills before engaging in real patient cases. Virtual patients allow the study of different scenarios regardless of the teaching staff availability, student location or, more important in dentistry, accessibility to patient, dental materials and different technologies. Considering the high standards of nowadays dentistry and, unfortunately, the limited possibilities in university clinics, the young doctors might find themselves in front of an overwhelming dilemma concerning material selection, appropriate technique and technology. The aim was to assess the qualitative general impact of VPs on dentistry students and the qualitative impact of two virtual clinical cases in particular, focusing on the selection of dental materials and on the suitable technology. 73 students participated in this study. The study comprised 5 stages: answer to an initial questionnaire regarding the students’ previous experience with VP software and their expectations related to the VP characteristics; incorporate the results of the initial questionnaire into building the two mentioned virtual cases; use built VPs in student training; answer to a final questionnaire recording the student feed-back to the VPs used; corroborate results from the two questionnaires to establish relevant qualitative features for VPs in dentistry. The results of the study are an important feed-back tool helping in developing and refining VPs with a high degree of acceptance, maximizing the educational efficiency of this learning method. Some of the most desired characteristics were: multimedia content, feed-back for good and bad decisions, low to medium degree of complexity, high coverage of course subjects. The use of VPs offers the chance of working with a broad range of dental materials (in a simulated mode) which is not normally possible in a real practice constrained by financial restrictions.

This study analyzed the lead behavior from CRT glass embedded in original composite materials exposed to different pH and temperature conditions. For this study were obtained composite materials with CRT glass (funnel) waste, some of them with zeolite addition, for lead chelating. The experimental results showed the pH and temperature influence lead leachability during the ultrasonic procedure and explained the influence of zeolites in lead behavior.

Injected plastic parts with internal threads (round, trapezoidal or saw) can increase products functionality but if not carefully designed can add unforeseen costs into the manufacturing process. In this paper the authors presents a computation methodology of the demolding moment for two cases of plastic injected parts with internal saw thread. This key parameter of the injection process directly influences the design solution of the ejector system. As further work the author will try to validate this method through a set of practical experiments.

The paper features several one-dimensional models to represent the rubber springs used in the dynamics simulations for the railway vehicles. Similarly, it includes a description of a model for the illustration of the mechanical behaviour of a mix coil spring - rubber employed in the secondary suspension of the passenger cars. The principle of this model relies on the overlapping of three components – elastic, viscous and the dry friction. The dependence of the force developed in the mix coil spring - rubber on the frequency and amplitude of a harmonic excitation is highlighted via the numerical simulations.