Preferred Language
Articles
/
jbcd-628
The influence of cavity design for cusp coverage on fracture strength of weakened maxillary first premolars using two esthetic restorative systems (CAD/CAM hybrid ceramic and nanohybrid composite) (An in vitro study)
...Show More Authors

Background: Maxillary first premolar with wide MOD cavity more susceptible to fracture. The aim of this study was to assess the influence of cavity design for cusp coverage on the fracture resistance of weakened maxillary first premolar restored with CAD/CAM hybrid ceramic versus nanohybide composite. Materials and Methods: Fifty six intact maxillary first premolars of approximately comparable sizes were divided into seven groups eight for each: Group A: Intact teeth (control group); Group B: teeth prepared for MOD inlay; Group C: teeth prepared for MOD onlay covering the lingual cusp; Group D: teeth prepared for MOD covering buccal and lingual cusps ,the previous three groups indirectly restored with nanohybrid composite (3M ESPE Z 250 XT); Group E,F,G prepared with the same design as group B, C, D respectively and restored with CAD/CAM hybrid ceramic (VITA ENAMIC). Results: An axial compression test was used to measure the fracture strength of experimented teeth. The readings were analyzed statistically by t-test, one way ANOVA and LSD, then the mode of fracture had been examined. The results showed that sound teeth in group (A) had more fracture resistance values than all experimental groups and the difference were highly significant with group (B, E, F, G).When the influence of cavity design tested among composite groups it showed highly significant difference between group (B) and (C)and the highest fracture resistance value was for group(C), whereas the influence of cavity design among Enamic groups showed highly significant difference between group (E) and (G) the highest fracture resistance value was for group(E).T-test between similar designs showed non-significant difference between MOD groups and highly difference between other groups. Conclusions: Cusp coverage increased the fracture resistance of composite groups but result in non-restorable fracture, while Enamic total onlay presented promising fracture resistance with favorable mode of fracture. Key words: Fracture resistance, CAD/CAM, hybrid ceramic, VITA ENAMIC, nanohybrid composite, cusp coverage.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Sep 01 2021
Journal Name
Iraqi Journal Of Physics (ijp)
Study the Effect of Graphene on the Contact Angle, Water Absorption and Thermal Stability ( TGA ,DSC) for Blend (Epoxy & Repcoat ZR)
...Show More Authors

In this study, polymeric coating was developed by incorporating nano graphene in the polymer blend with applications to oil storage tanks. The oil storage tanks samples were brought from the oil Pipeline Company / Doura refinery in Baghdad. The coating polymer was formed with a blend (epoxy resin and repcoat ZR). The proportion of mixing the mixture was 3:1:1 epoxy resin 21.06 gm: repcoat ZR 10.53 gm: hardener 10.53 gm. The blend/graphene was prepared using in stui-polymerization method with different weight percentage 1, 3, 5, and 7 wt % added to blend. The resulting solution was put in a glass tube on a magnetic stirrer for one hour at a temperature of 40 °C. The result of contact angle and water absorption the best ratio of 3wt

... Show More
View Publication
Crossref (1)
Crossref
Publication Date
Sat Oct 20 2018
Journal Name
Journal Of Economics And Administrative Sciences
Calculate the Average Run Length (ARL) to Detect the Deviation in the Process A case Study in an Industrial Organization
...Show More Authors

 

Statistical control charts are widely used in industry for process and measurement control . in this paper we study the use of markov chain approach in calculating the average run length (ARL) of cumulative sum (Cusum) control chart for defect the shifts in the mean of process , and exponentially weighted moving average (EWMA) control charts for defect the shifts for process mean and , the standard deviation . Also ,we used the EWMA charts based on the logarithm of the sample variance for monitoring a process standard deviation when the observations (products are selected from al_mamun factory ) are identically and independently distributed (iid) from normal distribution in continuous manufacturing .

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 01 2023
Journal Name
Journal Of Oral Medicine And Oral Surgery
Reliability of two difficulty indexes in predicting the surgical extraction difficulty of impacted mandibular third molars
...Show More Authors

Introduction: The aim of this study was to compare the reliability and the agreement of the Pederson and Pernambuco difficulty indexes in predicting the surgical extraction difficulty of the impacted mandibular third molars. Materials and methods: A prospective observational cohort study was conducted on 83 patients who had undergone surgical removal of impacted mandibular third molar. The difficulty of extraction was determined preoperatively according to the total scores obtained from the Pederson and Pernambuco difficulty indexes, the operative difficulty was determined by the surgical technique and the duration of extraction. The accuracy of prediction of the surgical difficulty and

... Show More
View Publication
Scopus (3)
Crossref (5)
Scopus Crossref
Publication Date
Wed Oct 05 2016
Journal Name
Al-academy
The Employment of Brainstorming in developing the idea of design of Fine Arts Institute Students in Designing the Technical Advertisement
...Show More Authors

Brainstorming is considered as one of the manners that develop learners' mental abilities. Besides, it can help learners get a lot of ideas and thoughts. And by following applied steps to answer the problem concerned, the researcher carried out this practical study aimed at:Developing the ideas of design of third year students/Institute of Fine Arts/Evening Studies- Baghdad/First Rusafa by employing Brainstorming mechanism to develop the ideas of design of institute students in designing the technical advertisement and to achieve the authenticity of the goal of the research, Department of Plastic Arts/Institute of Fine Arts/Evening Studies/Baghdad-First Rusafa was chosen as a case study for the research. It embraced (20) students who rep

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Feb 04 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Using Regression Analysis as Analytical Procedure to Facilitate the Decision-Making Process in The Tax Audit: An Applied Research in the General Commission of Taxes
...Show More Authors

This research aims to clarify the advantages of using the regression method as analytical procedure in the tax audit to reducing the examination cost , time, effort, human and material resources, and represents an applied study in the General Commission of taxes. In order to achieve its objectives the research has used in the theoretical side the descriptive approach (analytical), and in the practical side regression method has been applied to the research sample represented by the soft drinks company that is subject to the tax settlement for the year 2014, where the value of sales has been verified by using the regression method without conductinga comprehensive examination. The most important results of the research indicate that the r

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Mar 31 2022
Journal Name
Journal Of The College Of Education For Women
News of Zubarah Family- Unionists in Nishapur and their Scientific Contributions in the two Centuries (4-6 AH/10-12 AD)
...Show More Authors

This research is concerned with qualitatively studying the history of an ancient family, one of the most prominent noble, Alawite families, that assumed the position of the Student Union for the Alawite Supervision in the city of Nishapur in Khorasan during the centries (4-6 H./ 10-12 A.H.). Thus, the research aims to investgate the historical news, and the outstanding Zubarah figures who experience the supereme the religious, historical and scientific position in Khorasan generally and Nishapur particularily. It further aims at arriving at the true meaning of the name Zubarah, and to whom it was called, and the extent of this family’s affiliation to the noble Alawi House, and how they moved to live and settle in the cities of the East

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Comparison Study of Electromyography Using Wavelet and Neural Network
...Show More Authors

In this paper we present a method to analyze five types with fifteen wavelet families for eighteen different EMG signals. A comparison study is also given to show performance of various families after modifying the results with back propagation Neural Network. This is actually will help the researchers with the first step of EMG analysis. Huge sets of results (more than 100 sets) are proposed and then classified to be discussed and reach the final.

View Publication Preview PDF
Publication Date
Thu Nov 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
The mechanisms of generation of Unemployment in Iraq and its types and calculating the Disguised of it: Analytical Study for the period 2003-2015
...Show More Authors

     The objective of this study is to attempt to provide a quantitative analysis to the causes of unemployment  in Iraq and its mechanisms of generation, as well as a review of the most important  types of both visible and invisible unemployment, and an attempt to measure the disguised  unemployment  and analyze the causes. The problem of the research lies in the fact that the Iraqi Economy has been suffered  for  a long time although its characterized by abundant  physical and natural  resources, from the existence of the  phenomenon of unemployment  in the previous two types. Causing a lot of economic problems, represented by the great waste of resources and

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Aug 01 2021
Journal Name
Journal Of Mechanical Engineering Research And Developments
Slot Design Procedure for a NACA 4412 at High Angle of Attack
...Show More Authors

The main objective of the present work is to find a method increases the efficiency of the airfoil that is used for blade in wind turbine, wing in aircraft, propeller and helicopter (like NACA 4412). By overcoming the separation of flow at high angle of attacks, a slotted airfoil had been used and solved numerically through connecting the pressure side in the bottom surface with the suction side in the top surface of the airfoil to energize the separated flow. Slot exit, width and slope were considered as a parameters of slot configuration to determine the effective design of consideration. Reynolds number was taken as [1.6 x106 ] and the angle of attacks were ranged from (0o - 20o ). The numerical solution with Ansys Fluent commercial prog

... Show More
View Publication
Publication Date
Sun Sep 05 2010
Journal Name
Baghdad Science Journal
Design of six electrode Enzial electrostatic lens low aberrations for electron gun
...Show More Authors

A computerized investigation has been carried out on the design of six electrodes electrostatic lenses used in electron gun application. The Finite-Element Method (FEM) was used in the solution of Laplace equation for determine the axial potential distribution. The electron trajectory under zero magnification condition. The optical properties, spherical and chromatic aberrations, the object and image focal length and object and image position are calculated. A very good futures for the electron gun with these lenses have been computed where are a beam current of 8.7*10-7A can be supplied using cathode tip of radius 10nm.

View Publication Preview PDF
Crossref (1)
Crossref