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Comparison of root canal transportation and centering after instrumentation through conservative and traditional access cavities using different file systems
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Introduction:

While conservative access preparations could increase fracture resistance of endodontically treated teeth, it may influence the shape of the prepared root canal. The aim of this study was to compare the prepared canal transportation and centering ability after continuous rotation or reciprocation instrumentation in teeth accessed through traditional or conservative endodontic cavities by using cone-beam computed tomography (CBCT).

Materials and Methods:

Forty extracted intact, matured, and 2-rooted human maxillary first premolars were selected for this study. Teeth were equally divided into two groups according to the access cavity design (traditional or conservative). Each group (n = 20) was further subdivided according to instrumentation technique (n = 10) into rotary 2 shape and reciprocation R-motion file subgroups. The teeth were scanned pre and post instrumentation using Planmeca ProMax to obtain two CBCT images for each sample. Images were analyzed and root canal transportation and centering ability were calculated for both buccal and palatal roots at three levels from their apices (3, 5 to 7 mm).

Results:

Although conservative access cavities showed more canal transportation and less centering ability than the traditional one, there was no statistically significant difference (P > 0.05) between them at all levels. Furthermore, no statistically significant difference has been identified in the same parameter between the two instrumentation techniques (continuous rotation and reciprocation) (P > 0.05). However, longer instrumentation time was measured in the conservative group compared to traditional.

Conclusion:

The size of endodontic access cavity has no effect on root canal transportation and centering ability when instrumentation was performed using 2 shape and R-motion file systems.

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Publication Date
Mon May 14 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Comparison Between Different Approaches to Overcome the Multicollinearity Problem in Linear Regression Models
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    In the presence of multi-collinearity problem, the parameter estimation method based on the ordinary least squares procedure is unsatisfactory. In 1970, Hoerl and Kennard insert analternative method labeled as estimator of ridge regression.

In such estimator, ridge parameter plays an important role in estimation. Various methods were proposed by many statisticians to select the biasing constant (ridge parameter). Another popular method that is used to deal with the multi-collinearity problem is the principal component method. In this paper,we employ the simulation technique to compare the performance of principal component estimator with some types of ordinary ridge regression estimators based on the value of t

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Publication Date
Mon Feb 01 2016
Journal Name
International Journal Of Applied Mathematics & Statistical Sciences
Topological Structures Using Mixed Degree Systems in Graph Theory
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This paper is concerned with introducing and studying the M-space by using the mixed degree systems which are the core concept in this paper. The necessary and sufficient condition for the equivalence of two reflexive M-spaces is super imposed. In addition, the m-derived graphs, m-open graphs, m-closed graphs, m-interior operators, m-closure operators and M-subspace are introduced. From an M-space, a unique supratopological space is introduced. Furthermore, the m-continuous (m-open and m-closed) functions are defined and the fundamental theorem of the m-continuity is provided. Finally, the m-homeomorphism is defined and some of its properties are investigated.

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Publication Date
Sun Dec 30 2007
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Efficiency and Reliability of Reverse Osmosis Desalination Systems
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This study is concerned with the evaluation of the effect of Euphrates River water quality in Al-Samawa region during
the period 1984-2003 on efficiency and reliability of reverse osmosis desalination systems by calculating the calcium
sulfate scaling index depending on the following indicators: - TDS, Ca+2, Mg+2, Na+1, Cl-1, So4-2, HCO3-1. It was
found from data analysis that this index for these units is greater than permissible limit. Also, the fitted relationship
between this index and TDS is logarithmic, i.e. this index varies more rapidly than TDS, and consequently it is more
representative to the water quality than TDS.

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Publication Date
Tue Dec 01 2009
Journal Name
Al-khwarizmi Engineering Journal
Studying the Factors Effect on the Flowability of (ZnO – CuO/ Al2O3) Catalyst with Blending of Different Lubricants through Hopper
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One of the most important problems in tablet process is to control the flow of the catalyst through the hopper; Controlling the flow can be done either by changing the size of particles or added the different lubricant (stearic acid, starch, graphite) or blending of different lubricants. The study showed that we can control (increase or decrease) on the flow of the catalyst through the hopper by blending different lubricants for the constant percentage. The flow increasing when particles size (0.6 mm) and then decrease with or without lubricants, no effect on flow when particles size lower than (0.2 mm) with use that lubricants, and good flow on (0.4 mm) when use stearic acid and starch.

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Publication Date
Fri Jun 11 2021
Journal Name
Journal Of Baghdad College Of Dentistry
Management of trauma to the anterior segment of the maxilla: alveolar fracture and primary incisors crown and root fracture
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Background: An injury to both the primary and permanent teeth and the supporting structures is one of the most common dental problems seen in children. Splinting is usually difficult or impossible to perform in the primary dentition (due to diminutive room size and lack of patient cooperation). Healing must, therefore, occur despite mobility at the fracture line, usually resulting in interposition of connective tissue. In some instances, infection will occur in the coronal pulp. The present study reported a case of trauma to the anterior primary teeth and alveolar bone in a four year old child. The trauma has caused fracture to the crowns and roots of the primary anterior teeth. The following case was managed in a procedure that may

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Publication Date
Fri Jun 11 2021
Journal Name
Journal Of Baghdad College Of Dentistry
Management of trauma to the anterior segment of the maxilla: alveolar fracture and primary incisors crown and root fracture
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Background: An injury to both the primary and permanent teeth and the supporting structures is one of the most common dental problems seen in children. Splinting is usually difficult or impossible to perform in the primary dentition (due to diminutive room size and lack of patient cooperation). Healing must, therefore, occur despite mobility at the fracture line, usually resulting in interposition of connective tissue. In some instances, infection will occur in the coronal pulp. The present study reported a case of trauma to the anterior primary teeth and alveolar bone in a four year old child. The trauma has caused fracture to the crowns and roots of the primary anterior teeth. The following case was managed in a procedure that may prov

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Publication Date
Fri Oct 06 2017
Journal Name
Journal Of Engineering
Constructional Efficiency in Al_Ahwaar Traditional Architecture
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Constructional Efficiency in architecture in general is one of the most important standard success for any structure and a measure of its continuity and relevance across time and space. Given the importance of Al-Ahwaar environment that owned the spatial, environmental, economic and social elements had a prominent impact in creation of architecture patterns form to create special architectural and structural environment, which had many qualities and ingredients that contributed to its continuity and existence over the years. From the premise that man and his environment is the main goal to any architectural style,

Thus the research problem focusing on the lack of clarity of the previous literatures in its st

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Publication Date
Tue Dec 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Using Artificial Neural Network Models For Forecasting & Comparison
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The Artificial Neural Network methodology is a very important & new subjects that build's the models for Analyzing, Data Evaluation, Forecasting & Controlling without depending on an old model or classic statistic method that describe the behavior of statistic phenomenon, the methodology works by simulating the data to reach a robust optimum model that represent the statistic phenomenon & we can use the model in any time & states, we used the Box-Jenkins (ARMAX) approach for comparing, in this paper depends on the received power to build a robust model for forecasting, analyzing & controlling in the sod power, the received power come from

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Publication Date
Fri Mar 01 2024
Journal Name
Baghdad Science Journal
A Comparison between Ericson's Formulae Results and Experimental Data Using New Formulae of Single Particle Level Density
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The partial level density PLD of pre-equilibrium reactions that are described by Ericson’s formula has been studied using different formulae of single particle level density . The parameter  was used from the equidistant spacing model (ESM) model and the non- equidistant spacing model (non-ESM) and another formula of  are derived from the relation between  and level density parameter . The formulae used to derive  are the Roher formula, Egidy formula, Yukawa formula, and Thomas –Fermi formula. The partial level density results that depend on  from the Thomas-Fermi formula show a good agreement with the experimental data.

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Publication Date
Wed Nov 04 2020
Journal Name
Advances In Mobility-as-a-service Systems
Community Participation Towards Sustainability Enhancement of Transportation Sector for Baghdad City
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