Preferred Language
Articles
/
jbcd-3316
Crystallization firing effect on the marginal discrepancy of the IPS. emax CAD crowns using two different CAD/CAM systems
...Show More Authors

Background: Marginal adaptation is critical for long – term success of crown and bridge restoration. Computer aided design / computer aided manufacture (CAD/ CAM) system is gaining more importance in the fabrication of dental restoration. Objective: The aim of this study is to evaluate the effect of crystallization firing on the vertical marginal gap of IPS. emax CAD crowns which fabricated with two different CAD/CAM systems .Materials and Methods: Twenty IPS e.max CAD crowns were fabricated. We had two major groups (A, B) (10 crowns for each group) according to the CAD/CAM system being used: Group A: fabricated with Imes - Icore CAD/CAM system; Group B: fabricated with In Lab Sirona CAD/CAM system. Each group was subdivided into two subgroups pre-crystallized (Group A1, B1) and crystallized crowns (Group A2, B2). At four points on each aspect of the crown, marginal gaps were assessed on the master metal die by using digital microscope at a magnification of (110X) and image- J program. The measurement was done twice for each crown; before and after crystallization process.Results: The lowest mean of marginal gap before and after crystallization was (29.387±2.774μm) and (70.108±5.569μm) respectively for Group A (Imes - Icore system) and the highest mean value before and after crystallization was (51.728 ±3.774μm) and (84.071 ±4.567μm) respectively for Group B (Sirona system). Paired sample t-test result showed a statistically highly significant difference in marginal gap between all groups.Conclusions: The crystallization process increases the vertical marginal gap. Imes - Icore system showed the lower marginal gap than Sirona system. The two systems have an acceptable marginal gap

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Apr 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of the Synthesis Time on Structural Properties of Copper Oxide
...Show More Authors

The structural properties of the CuO nanopowder oxide prepared reflux technique
without any templates or surfactant, using copper nitrate hydrate (Cu(NO)3 3H2O) in deionized
water with aqueous ammonia solution are reported. The Xrd analysis data and processing in origin
pro program used to get FWHM and integral width to study the effect of different synthesis times
was studied on the structural properties. It was found that values of crystal sizes are 17.274nm,
17.746nm, and 18.560nm, the size of nanoparticles is determined by Halder-Wagner, and 15.796
nm, 15.851nm, and 16.52nm, were calculated by Size-Strain Plot (SSP) method. The Sample was
considered to determine physical and microstructural paramete

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Jun 20 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Evaluation of marginal gap at the composite/enamel interface in Class II composite resin restoration by SEM after thermal and mechanical load cycling (An in vitro comparative study)
...Show More Authors

Background: This study compared in vitro the marginal adaptation of three different, low shrink, direct posterior composites Filtekâ„¢ P60 (packable composite), Filtekâ„¢ P90 (Silorane-based composite) and Sonic fillâ„¢ (nanohybrid composite) at three different composite/enamel interface regions (occlusal, proximal and gingival regions) of a standardized Class II MO cavity after thermal changes and mechanical load cycling by scanning electron microscopy. Materials and methods:Thirty six sound human maxillary first premolars of approximately comparable sizes were divided into three main groups of (12 teeth) in each according to the type of restorative material that was used: group (A) the teeth were restored with Filtekâ„¢ P6

... Show More
View Publication Preview PDF
Publication Date
Thu Jun 30 2011
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
A PARTICULAR SOLUTION OF THE TWO AND THREE DIMENSIONAL TRANSIENT DIFFUSION EQUATIONS
...Show More Authors

A particular solution of the two and three dimensional unsteady state thermal or mass diffusion equation is obtained by introducing a combination of variables of the form,
η = (x+y) / √ct , and η = (x+y+z) / √ct, for two and three dimensional equations
respectively. And the corresponding solutions are,
θ (t,x,y) = θ0 erfc (x+y)/√8ct and θ( t,x,y,z) =θ0 erfc (x+y+z/√12ct)

View Publication Preview PDF
Publication Date
Mon May 20 2019
Journal Name
The Journal Of Engineering
Experimental comparison of two linear machines developed for the free piston engine
...Show More Authors

: In this study, a linear synchronous machine is compared with a linear transverse flux machine. Both machines have been designed and built with the intention of being used as the power take off in a free piston engine. As both topologies are cylindrical, it is not possible to construct either using just flat laminations and so alternative methods are described and demonstrated. Despite the difference in topology and specification, the machines are compared on a common base in terms of rated force and suitability for use as a generator. Experience gained during the manufacture of two prototypes is described.

View Publication Preview PDF
Crossref (9)
Clarivate Crossref
Publication Date
Sun Dec 07 2014
Journal Name
Baghdad Science Journal
Baysian and NonBaysian Methods to Estimate the two parameters of Logistic Distribution
...Show More Authors

In this paper ,the problem of point estimation for the two parameters of logistic distribution has been investigated using simulation technique. The rank sampling set estimator method which is one of the Non_Baysian procedure and Lindley approximation estimator method which is one of the Baysian method were used to estimate the parameters of logistic distribution. Comparing between these two mentioned methods by employing mean square error measure and mean absolute percentage error measure .At last simulation technique used to generate many number of samples sizes to compare between these methods.

View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Fri Jun 20 2025
Journal Name
Journal Of Physical Education
Proposed Exercises Using Flexible Resisters And Their Effect On Developing Strength Endurance And The Performance of Some Offensive Skills In Youth Basketball
...Show More Authors

View Publication
Publication Date
Fri Jun 20 2025
Journal Name
Journal Of Physical Education
The Effect of Electric Stimulation Using Proposed Apparatus on Static Balance Through Hamstring Muscle Rehabilitating in Athletes Suffering from Mild Muscle Tear
...Show More Authors

View Publication
Publication Date
Mon May 01 2023
Journal Name
Journal Of Physical Education
The Effect of Electric Stimulation Using Proposed Apparatus on Static Balance Through Hamstring Muscle Rehabilitating in Athletes Suffering from Mild Muscle Tear
...Show More Authors

KS Ismaeil, BR Jawad, Journal of Physical Education, 2023

View Publication
Publication Date
Thu Dec 29 2016
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Study the Effect of Method of Preparing on the Structure Properties of (PbS) Thin Films
...Show More Authors

    In this research we prepared PbS thin films with vacuum thermo evaporation process and  chemical spray pyrolysis.         Structure properties were studied for PbS thin films through (XRD) measurement. PbS thin films growth appear as Polycrystalline cubic and sharp peak with directional (200) then  calculated   Lattice constant (a) and the values are (5.9358)Ã… for (PbS) films prepared by thermo evaporation , (2.978-5.969 Ã…) for films prepared by chemical spray pyrolysis at temperature degree   (553K , 573K)  sequence .Then it was found that the grain size for (PbS) thin films prepared by thermo evaporation is (335.81)Ã… while the grai

... Show More
View Publication Preview PDF
Publication Date
Fri Jan 11 2019
Journal Name
Iraqi Journal Of Physics
A study of the effect of nano materials on the physical properties of epoxy composites
...Show More Authors

This research studies the effect of addition of some nanoparticles
(MgO, CuO) and grain size (30,40nm) on some physical properties
(impact strength, hardness and thermal conductivity) for a matrix
blend of epoxy resin with SBR rubber. Hand –Lay up method was
used to prepare the samples. All samples were immersed in water for
9 weeks.
The Results showed decreased in the values of impact strength and
hardness but increased the coefficient of thermal conductivity.

View Publication Preview PDF
Crossref (2)
Crossref