Background: This in vitro study was carried out to evaluate the effects of various veneering dentin ceramic thicknesses and repeated firings on the color of lithium disilicate glass-ceramic (IPS e.max Press) and zirconium-oxide (IPS ZirCAD) all-ceramic systems, measured by clinical spectrophotometers (Easyshade Advance 4.0) . Materials and methods: The 72specimens cube-shaped have the dimension of about 11 mm in width, 14 mm in length, 1mm in thickness, these cores divided into 3 groups according to the type of material each group have (24)core specimens. Each group had been divided into three sub-groups (each having 8 specimens) according to veneering with dentin ceramic thicknesses: as 0.5, 1, or 2 mm (n=8). IPS e.max press and ZirCAD cores group had been veneered with IPS e.max Ceram dentin ceramic shade A2 according to manufacturer’s instructions and the metal group had been veneered with IPS classic dentine ceramic with shade A2 according to manufacturer’s instructions. Repeat firings (3, 5 and 7 times) had been applied on all the specimens. Color differences among ceramic specimens had been measured using a clinical spectrophotometer (VITA Easyshade); the color data had been expressed according the Vita Classic shade guide. Results: The shade of all specimens had been compared inside the subgroups and with the main groups. The percentage of color agreement among the subgroups showed the color of all ceramic systems had been affecting by firing interval, the ceramic thickness and brand of ceramic. The number firings intervals applied on the all ceramic system has a significant effect on the final color, the increase of firing number change the color to a darker and reddish color. The 5th firing interval is the point at which the major color changes happened (darker shade), and in next interval (7th firing) less color changes happened. The thickness of veneering ceramic affected the color significantly. The 0.5 mm specimens in all groups showed the highest percentage of agreement (less color changes) after firing intervals, then the 1mm came and the least percentage of agreement ( highest color changes ) was the 2 mm specimens. The Brand of veneering ceramic and the type of core record a significance difference in color changes when exposed to firing heat. Conclusion: With limit of this study, the final color of the all ceramic system definitely affected by the number of firing cycle exposed to, and the veneering ceramic thickness have a clear effect on the final shade of the all ceramic tested.
There is a real problem when adding micro elements to the soil as a result of fixation, sedimentation, washing or toxicity, and thus economic loss. The plant needs micro elements in very small quantities that do not burn the leaves or cause poisoning to plants, including iron, zinc and boron, as they are essential elements for growth and completing the plant's life cycle, and increase the plant's resistance to diseases and insects, activate enzymes, and form the chlorophyll molecule, in addition to their role in oxidation and reduction processes and vital processes. The use of fertilizers with their modern technology has made the process of activating seeds or foliar nutrition a matter of interest to researchers as a complementary process t
... Show MoreThe current research aims to diagnose the extent of interest in knowledge sharing and its role in achieving organizational excellence at the level of the Iraqi environment Primary data through descriptive statistics (arithmetic mean, standard deviation, coefficient of variation, percentages, frequencies) and hypothesis testing using appropriate statistical methods for inferential statistical analysis (Pearson correlation coefficient, simple linear regression, multiple regression, path analysis) and checking the quality of the data from During (normal distribution, confirmatory factor analysis, structural modeling method, and exploratory factor analysis), after collecting data from (358) observations from the company’s leaders, as
... Show MoreDBN Rashid, Rimak International Journal of Humanities and Social Sciences, 2020
Judicial jurisprudence is one of the important legal solutions to address the shortcomings of legislation. Throughout its long history, human societies have known many cases in which the judge finds himself facing a legislative vacuum in addition to civil legal texts that are difficult for the judge to implement due to ambiguity or contradiction, which requires diligence. To rule on resolving disputes before him in order not to deny justice, but the judge in his jurisprudence was not absolute, but rather bound by certain controls represented by observing the wisdom of legislation on the one hand and taking into account the nature of the texts on the other side, and from here this research came to shed light on the jurisprudence and its cont
... Show MoreAromaticity reversals between the electronic ground (S0) and low-lying singlet (S1, S2) and triplet (T1, T2, T3) states of naphthalene and anthracene are investigated by calculating the respective off-nucleus isotropic magnetic shielding distributions using complete-active-space self-consistent field (CASSCF) wavefunctions involving gauge-including atomic orbitals (GIAOs). The shielding distributions around the aromatic S0, antiaromatic S1 (1Lb), and aromatic S2 (1La) states in naphthalene are found to resemble the outcomes of fusing together the respective S0, S1, and S2 shielding distributions of two benzene rings. In anthracene, 1La is lower in energy than 1Lb, and as a result, the S1 state becomes aromatic, and the S2 state becomes anti
... Show MoreObjective: The aim of this study to detect the correlation between trace elements such as zinc, copper and
spermatogenesis, sperm viability and motility.
Methodology: Serum and semen samples were collected from one hundred twenty patients with age ranged (20-
50 years) attending the high institute for Embryo Research and Infertility Treatment/ Baghdad University, in
addition to thirty fertile males their age comparable to that of patients. The period of this study was from June
2004 until the end of October 2004.
Results: The result of routine seminal fluid analysis of all infertile males was divided according to WHO, (1999) limit
into four groups: Asthenospermia(A), Asthenoteratospermia(AT), Oligoasthenoteratospermi
Aim: The purpose of this study was to analyze the patterns of facial fractures in children and to compare them between preschool- and school-aged children. Materials and methods: This retrospective observational study included 57 children with facial fractures. The variables analyzed were the age of the patients—divided into a preschool-aged group (0–5 years) and a school-aged group (6–12 years)—gender, cause of trauma, the facial bones involved, the pattern of fracture, the modality of treatment used, the time between injury and treatment, and the postoperative complications. Results: The incidence of facial fractures in children ≤12 years was 30.2%. The patients consisted of 40 (70.2%) males and 17 (29.8%) females, and most pati
... Show MoreThe primary objective of this paper is to introduce a new concept of fibrewise topological spaces on D is named fibrewise multi- topological spaces on D. Also, we entroduce the concepts of multi-proper, fibrewise multi-compact, fibrewise locally multi-compact spaces, Moreover, we study relationships between fibrewise multi-compact (resp., locally multi-compac) space and some fibrewise multi-separation axioms.
اليورانيوم المنضب واستخدامه امريكياً في العراق