Background: This in vitro study was carried out to investigate the effect of post space regions (coronal, middle and apical), the effect of post types ( Manually Milled Zirconia post, Prefabricated Fiber post, prefabricated Zirconia post) and the type of cement used (GIC, self-adhesive resin cement) on the bond strength between the posts and root dentin by using push-out test. Material and methods: Forty eight mandibular premolars extracted for orthodontic reasons (single rooted) were instrumented with ProTaper system (hand use) and obturated with gutta percha for ProTaper using AH26® root canal sealer following the manufacturer instructions. After 24 hours, post space was prepared using Zirix and Glassix drills no.3 creating 8 mm depth post space. The prepared samples were randomly divided into three main groups (16 samples each) according to the type of post used (Group A. Manually Milled Zirconia post, Group B. Prefabricated Fiber post and Group C. Prefabricated Zirconia post) .each group was subdivided into two subgroups (each subgroup contains 8 samples) according to the type of cement used (subgroup A1.Manually Milled Zirconia post cemented with GIC, subgroup A2.Manually Milled Zirconia post cemented with Speed cem),( subgroup B1.Prefabricated Fiber post cemented with GIC, Group B2. Prefabricated Fiber post cemented with Speed cem) and (subgroup C1.Prefabricated Zirconia post cemented with GIC, subgroup C2. Prefabricated Zirconia post cemented with Speed cem), after cementation and incubation for 24hrs, at 37°c and 100% humidity. Each root was sectioned horizontally into 3 slices (2 mm in thickness) representing the coronal, middle and apical regions of the post space. Push out bond strength test was performed and measured using a universal testing machine (Tinius-Olsen) at across head speed of 0.5 mm/min. Results: The results showed that regarding the root region, the bond strength values increased significantly from apical to coronal region for all types of posts in both tested cements. For the effect of post type, the manually Milled Zirconia post cemented with the self-cured resin cement (Speed cem) showed higher bond strength values. For type of cement, the self-adhesive resin cement (Speed cem) showed higher bond strength values. Conclusions: the retention of post restoration was affected by root region, type of post and type of cement used.
There is no doubt that each of the arts has a material from which the aesthetic achievement is built, so the researcher found that the art of theater, especially the show, whose artistic achievement is based on the body of the actor who emits the formal language (body language), is the focus of interest and active presence, because the body possesses its spiritual qualities that made him and the ability to The formation of things by (his body language), so the researcher studied this theatrical phenomenon and divided it into four chapters. In the first chapter, the research problem included the following question: (Is there a phenomenon of body language in the contemporary theatrical show "Imagine that" as a model) so It is of cognitive
... Show MoreA mathematical model has been introduced to investigate the effect of nuclear reaction constant ( A ), probability of the BEC ground state occupation Ω i, nD is the number density of deuteron (d) and the overall number of nuclei ND on the total nuclear d-d fusion rate (R). Under steady-state of the condensates of Bose-Einstein, the postulate of quantum theory and Bose-Einstein theory were applied to evaluate the total nuclear (d-d) fusion rate trapping in Nickel-metal The total nuclear fusion rate trapping predicts a strong relationship between astrophysical S-factor and masses of Nickel. The reaction rate trapping model was tested on three reaction d(d,p)T, d(d, n)3He and d(d, 4He)Q = 23.8MeV respectively. The reaction rate has described
... Show MoreThe purpose of my thesis is to synthesis two new bidentate ligands which were used to prepare series of metal complexes by reacting the ligands with (M+2 = Mn, Co, Ni, Cu, Cd and Hg) Succinyl chloride was used as starting material to synthesis two bidentate ligands (L1) and (L2) by reaction it with 4-chloroaniline (L1) and (4-aminoacetophenone) (L2) in dichloromethane as a solvent, that are: (L1) = N1,N4-bis (4-chloro phenyl ) succinamide (L2) =N1,N4-bis(4-acetylphenyl)succinamide The new ligands were characterize by using spectroscopic study (Fourier-transform infrared spectroscopy (FT-IR), electronic spectra ( UV-Vis) ,nuclear magnetic resonance(1H,13C-NMR), Mass spectra
... Show MoreA total of 30 specimens of house sparrow Passer domesticus biblicus Hartert, 1904 (15 females and 15 males) were collected from gardens of some houses in Baghdad city; all birds were dissected to identify the parasites in vesicle, gizzard, intestine, gall bladder and caecum. One species of trematodes Brachydistomum microscelis (Yamaguti, 1933) was found in the gall bladder and two species of cestodes Anonchotaenia globata (von Linstow, 1879) and Raillietina tetragona (Molin, 1858) were found in the small intestine of house sparrow. Morphologic and morphometric measurements were considered.
The genus Brachydistomum Travassos, 1944 is being recorded for the first time in Iraq in the gall bladder of house sparr
... Show MoreThe liability limit liability limit and reinsurance re factors insurance are important in influencing the achievement of company's competitive goals and achieve success and excellence in the market and because the limit of liability and reinsurance aimed to increase output with the stability of inputs leading to increased insurance business and increase profits. The study was based on two variables presidents interact with each other to form the intellectual and philosophical framework has two ( the limit of liability and reinsurance ) . The study was launched from a problem expressed by a number of targeted questions answered from the elucidation of theoretical philosophy and intellectual goals of these variables and highlight the impor
... Show MoreThe research illustrated that the theory of constraints is "A group of concepts and basics that aim at helping the management in order to determine the difficulties and how to overcome these difficulties through determining the necessary change and how these change can be done efficiently and effectively ".
The research showed that the theory of constraint including its tools calls for magnifying throughput, constricting the product cycle , determining the optimal production mix , utilization of scare resources and canceling the idle time , that achieving throughput increasing then increasing profit .
Moreov
... Show MoreThe Iraqi marshes are considered the most extensive wetland ecosystem in the Middle East and are located in the middle and lower basin of the Tigris and Euphrates Rivers which create a wetlands network and comprise some shallow freshwater lakes that seasonally swamped floodplains. Al-Hawizeh marsh is a major marsh located east of Tigris River south of Iraq. This study aims to assess water quality through water quality index (WQI) and predict Total Dissolved Solids (TDS) concentrations in Al-Hawizeh marsh based on artificial neural network (ANN). Results showed that the WQI was more than 300 for years 2013 and 2014 (Water is unsuitable for drinking) and decreased within the range 200-300 in years 2015 and 2016 (Very poor water). The
... Show MoreA new method for construction ion-selective electrode (ISE) by heating reaction of methyl orange with ammonium reineckate using PVC as plasticizer for determination methyl orange and determination Amitriptyline Hydrochloried drug by formation ion-pair on electrode surface . The characteristics of the electrode and it response as following : internal solution 10-4M , pH (2.5-5) ,temperature (20-30) and response time 2 sec. Calibration response for methyl orange over the concentrationrange 10-3 -10-9 M with R=0.9989 , RSD%=0.1052, D.O.L=0.315X10-9 MEre%=(-0.877- -2.76) , Rec%.=(97.230 -101.711) .
The research problem revolves around the Iraqi public's use of digital television and cinematic websites، and their importance to the academic study and society، as it examines the public's relationship with these websites، usage habits، and the reasons for their interaction with them. And for the prevalence of this phenomenon of use، it was necessary to address the intensity، intentionality، and timing of use to theoretically root the subject of the study، which is one of the modern studies in Iraq and the Arab world. The survey approach، where the research was based on the theory of uses and gratifications that confer positivity and activity on the mass media audience.
The researchers designed
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