Preferred Language
Articles
/
jbcd-2932
The effect of composite bonding spot size and location on the performance of poly-ether-ether-ketone (PEEK) retainer wires
...Show More Authors

Background: Poly-ether-ether-ketone(PEEK) has been introduced to many dental fields. Recently it was tested as a retainer wire‎ following orthodontic treatment. This study aimed to investigate the effect of changing the bonding spot size and location on the performance of PEEK retainer wires. Methods: A biomechanical study involving four three-dimensional finite element models was performed. The basic model was with a 0.8 mm cylindrical cross-section PEEK wire, bonded at the center of the lingual surface of the mandibular incisors with 4 mm in diameter composite spots. Two other models were designed with 3 mm and 5 mm composite sizes. The last model was created with the composite bonding spot of the canine away from the center of the crown, closer to the lateral incisor. The linear displacement of the teeth, strains of the periodontal ligament, and stresses in PEEK wire and composite were evaluated. The data was numerically produced with color coded display by the software. Selected values were tabulated and compared among models. Results: The amount of linear displacement and strain was very low. Stresses in the wire and composite were affected by the size and position of the composite bonding spot. The safe limits were identified at 235 MPa for PEEK and 100 MPa for composite. The basic model had a von Mises stress in the PEEK wire of 122.09 MPa, and a maximum principal stress in the composite of 99.779 MPa. Both stresses were within the safe limits, which means a lower risk of failure in PEEK and composite. All other models had stresses that exceeded the safe limit of the composite. The 3 mm composite model was the only one that developed stresses in the wire more than the safe limits of PEEK. Conclusions: Within the limitations of this study, bonding PEEK wires with 4 mm bonding spots to the clinical crown center provided the best mechanical performance of the wires and spots; otherwise, the mechanical properties of the wire and composite would be affected and, therefore, might affect the retention process. Keywords: Retention, PEEK, Finite element analysis

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Dec 31 2022
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
EFFECT OF NITROGEN FERTILIZERS ON GROWTH AND YIELD TRAITS OF MAIZE: EFFECT OF NITROGEN FERTILIZERS ON GROWTH AND YIELD TRAITS OF MAIZE
...Show More Authors

 

ABSTRACT

A field experiment was carried out in the fields of the college of agricultural engineering sciences, university of Baghdad during the fall season of 2021, in order to find out which of the cultivated genotypes of maize are efficient under nitrogen fertilization. The experiment was applied according to a RCBD (split plot design with three replications). The genotypes of experiment (Baghdad, 5018 and Sarah) and  supplying three levels of nitrogen fertilizer, which are N1 (100 kg/ha),  N2 (200 kg/ha) and N3  (300 kg/ha), the results of the statistical analysis are showed the superiority of the cultivar Sarah in the trait of number of days until 50% silking, chlorophyll

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 06 2025
Journal Name
Journal Of Physical Education
The Effect of Proposed Exercises Using Sponge Mat On the Level of Performing Offensive Skills in Sitting Volleyball
...Show More Authors

View Publication
Publication Date
Sun Apr 22 2018
Journal Name
Al-nahrain Journal For Engineering Sciences
Numerical Analysis of the Effect of Scanning Speed on the Temperature Field Distribution for Laser Heat Treatment Applications
...Show More Authors

One of the unique properties of laser heating applications is its powerful ability for precise pouring of energy on the needed regions in heat treatment applications. The rapid rise in temperature at the irradiated region produces a high temperature gradient, which contributes in phase metallurgical changes, inside the volume of the irradiated material. This article presents a comprehensive numerical work for a model based on experimentally laser heated AISI 1110 steel samples. The numerical investigation is based on the finite element method (FEM) taking in consideration the temperature dependent material properties to predict the temperature distribution within the irradiated material volume. The finite element analysis (FEA) was carried

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
effect of doping with nitrogen on the optical constant of the sic films prepared by TEA-Co2 Laser
...Show More Authors

In this research prepare membranes pure silicon carbide (SiC) as well as gas Alloy (ammonia) and using a laser was leaked membrane of glass flooring. To Drasesh optical properties of membranes prepared depending on the technique (Swanepoel) and Adhrt results obtained in general increased permeability pure silicon membranes

View Publication Preview PDF
Publication Date
Sat Dec 05 2020
Journal Name
Iop Conference Series: Materials Science And Engineering, Volume 1067
The effect of cyclic loading on the nonlinear response of structural concrete members with arbitrary cross-sectional shapes
...Show More Authors

View Publication
Publication Date
Mon May 15 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Potentiostatic Study for the effect Of LAS on the Corrosion Of pure Zinc in 0.01 M HCl solutions
...Show More Authors

   A potentiostatic study for the corrosion of pure zinc in 0.01 M HCl was achieved in absence and presence of (linear alkylbenzene solfonate LAS) detergents in a range of concentrations (0-50) mg/L. The electrochemical studies included anodic, cathodic polarization by using potentiostat over temperature rang (293- 323) K.     The mechanism of corrosion rate of pure zinc was suggested by evaluating of αa , αc , ba , bc , i0 , Rp and the kinetic parameters also calculated ( Ea , A) at the above temperature rang, The thermodynamic of corrosion, corrosion accelerating and corrosion  protecting were investigated by calculating  (∆G, ∆H and ∆s) values

View Publication Preview PDF
Publication Date
Thu Jul 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Effect of substrate Nature on the properties of Tin Sulfide Nanostructured films Prepared by chemical bath deposition
...Show More Authors

The substrate's nature plays an important role in the characteristics of semiconductor films because of the thermal and lattice mismatching between the film and the substrate. In this study, tin sulfide (SnS) nanostructured thin films were grown on different substrates (polyester, glass, and silicon) using a simple and low-cost chemical bath deposition technique. The structural, morphological, and optical properties of the grown thin films were investigated using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and ultraviolet-visible-near infrared (UV-Vis-NIR) spectroscopy. The XRD and FESEM results of the prepared films revealed that each film is polycrystalline and exhibits both orthorhombic and cubic stru

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 12 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Direct Damaging Effect of Some Agricultural Chemicals Used Locally in Iraq on the DNA of Escherichia coli
...Show More Authors

      Agricultural chemicals on a large scale of use throughout the world, and there are many studies about these chemicals and its disadvantages, but most of them were limited to its impact on mammals such as rodents in determine. This study was designed to determine the impact of these chemicals on DNA damage for E. coli bacteria from Iraq. The DNA is similar in terms of structure and function in all living organisms with a different in number and sequence of the nitrogenous bases among living organisms.            This study showed that snails and slugs killer material Metaldehyde are strongly bind with the DNA extracted from bacteria, and herbicides Glyph

... Show More
View Publication Preview PDF
Publication Date
Wed Nov 04 2015
Journal Name
Journal Of Chemical, Biological And Physical Sciences
The Effect of Alkaloid Extracted from Cordia myxa Leaves on the Survival of Mustard Aphid Lipaphis erysimi (Kalt.)
...Show More Authors

Publication Date
Sat Jan 01 2022
Journal Name
Communications In Mathematical Biology And Neuroscience
The effect of fear on the dynamics of two competing prey-one predator system involving intra-specific competition
...Show More Authors

View Publication
Scopus (8)
Crossref (2)
Scopus Clarivate Crossref