Background: The purpose of this study was to evaluate and compare centering ability and canal transportation of simulated S-shaped canals instrumented with four different types of rotary nickel-titanium systems. Materials and Methods: Forty simulated S-shaped canals in resin blocks were divided into four groups of ten each and were instrumented to an apical size 25 by different instrumentation technique using ProTaper Universal files (group A), ProTaperNext (group B), Reciproc (group C) and WaveOne (group D).Centering ability and canal transportation was measured at (11) measuring points from D0 to D10 bysuperimposion of the pre- and post-operative images obtained by using digital camera in standardized manner. An assessment of the canals shape was determined using Photoshop CS2 and AutoCAD software. The data were analyzed statistically using ANOVA and LSD test. Results: In terms of centering ratio values, there was no statistically significant difference among the four groups at the coronal portion of the canals, with ProTaper system showing the least centering ability at all levels except at apical foramen. At the apical curvature, the Reciproc and WaveOne groups showed better centering ability than ProTaperNext and the difference was statistically highly significant among them at these points, while at the coronal curvature the ProTaperNext showed better centering ability than Reciproc and WaveOne. Canal transportation was seen in all groups but the ProTaper systems showed more transportation values at almost levels when compared with the other groups with the least values by ProTaperNext at the coronal curvature and the least values by Reciproc and WaveOne at the apical curvature. Conclusions: Under the conditions of this study, ProtaperNext ,WaveOne and Reciproc instruments maintained the original curvature significantly better than ProTaperUniversal at almost levels. ProtaperNext showed a better shaping ability than Reciproc and WaveOne at the coronal curved section while at apical curved section Reciproc and WaveOne showed a better shaping ability than ProtaperNext. Key words: centering ability, canal transportation, ProTaperNext, Reciproc, WaveOne.
The effect of different doping ratio (0.3, 0.5, and 0.7) with thickness in the range 300nmand annealed at different temp.(Ta=RT, 473, 573, 673) K on the electrical conductivity and hall effect measurements of AgInTe2thin film have and been investigated AgAlxIn(1-x) Te2 (AAIT) at RT, using thermal evaporation technique all the films were prepared on glass substrates from the alloy of the compound. Electrical conductivity (σ), the activation energies (Ea1, Ea2), Hall mobility and the carrier concentration are investigated as a function of doping. All films consist of two types of transport mechanisms for free carriers. The activation energy (Ea) decreased whereas electrical conductivity increases with increased doping. Results of Hall Effect
... Show MoreBackground: Sclerotherapy is a simple treatment modality for treatment of infantile hemangioma and slow-flow vascular malformations; Polidocanol is a mild sclerosing agent that is traditionally used in treatment of varicose veins. This study aims to evaluate the effectiveness, treatment outcome, and complications of polidocanol foam sclerotherapy for infantile hemangioma and slow-flow vascular malformations. Materials and methods: Between March 2013 and December 2014, seventeen patients with infantile hemangioma and slow-flow vascular malformations treated with polidocanol 1% foam sclerotherapy. Foam was prepared by Tessari’s method. Injection performed under general or local anesthesia, injections were repeated (if necessary) on mon
... Show MoreThe study of sex Structure and age characteristics of an important element of the
follow-up changes between different population groups, which are connected to a large degree
the demographic, social and economic characteristics, particularly since each population
group varying characteristics in terms of age, sex entail social, demographic, cultural and
economic implications, and from that the researcher has taken from Structure of sex and age
for population in the district of Tuz Khurmatu for (1997-2012 ) the subject of consideration
and maintain compared to see the contrast between them. Qualitative Research for installation
and the age of the urban and rural areas has touched the judiciary, as well as its respects
Objective(s): The aim of this study is to compare the impact strength of a heat cured denture-base acrylic resin
reinforced with metal wire and glass fibers.
Methodology: Forty five specimens were prepared from pink heat cure acrylic resin. Specimens were grouped into;
group-I (control group) which consists of 15 specimens with no reinforcement, group-II which consists of 15 specimens
reinforced with metal wire, and group-III consists of 15 specimens reinforced with glass fibers. Specimens were tested
by using charpy impact machine.
Results: The result showed that there was a highly significant difference in impact strength value among the testing
groups at (P < 0.001).
Conclusion: The impact str
... Show MoreThe competitive environment influences the increase in exercise intensity and hence adds to the growth of training and practice. The study objective.to identify the effect of competitive speed exercises on the effectiveness of skill performance and speed of counterattack for junior boxers, as well as to know the rate of development for these variables.Materials and methods. The research sample consisted of twelve up-and-coming Al-Najda Sports Club players who participated in the national tournament and were selected with care. They were placed into two groups, control and experimental, with six boxers each in the control and experimental groups. The two groups were assigned identical weights on purpose, and their ages range from 15 to 16 ye
... Show MoreCognitive methods play the role of regulator of the human environment for its direct relationship with sensory stimuli and stimuli associated with the organization of information and ideas and their preparation for use in subsequent situations. These methods determine the characteristic or ideal way of individual personality in the differentiation and integration of attitudes or cognitive field to which he is exposed. Therefore, the research aimed at the level of psychological stress and its relation to some personal characteristics that show the personality of the artist or the students of art.
Current research aims to.
- Identifying the extent of psychological stress and its relation to the personal ch
This research is addressing the effect of different ferrocene concentration (0.00, 2.15x10-3, 4.30x10-3, 8.60x10-3, and 12.9x10-3) on the bulk free radical polymerization of methyl methacrylate monomer in benzene using benzoyl peroxide as initiator. The polymerization was conducted at 60º C under free oxygen atmosphere. The resulting polymers were characterized by FTIR. The results were compared with the presence and absence of ferrocene at 10% conversion. The %conversion was 3.04% with no ferrocene present in the polymerization medium and its increase to 9.06 with a first lowest ferrocene concentration added, i.e. 2.15 x10-3mol/l. This was positively reflected on the poly(methyl methacrylate) molecular weight measured by viscosity techniq
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