Background: This clinical trial aims to evaluate the color changes of direct resin composite veneer (DCV) restorations based on spectrophotometric analysis of 4 different types of resin composites between the baseline immediately after polishing and after one year of follow-up. Materials and methods: 28 patients were assessed for eligibility for participation, aged between 18 and 38 years old, who indicated for DCV restorations in anterior maxillary teeth were considered for participation in this study. In total, 25 patients who met the inclusion criteria were selected (6 males and 19 females, mean age: 20.9 at the time of restoration placement), and 3 patients were excluded. Participants were divided into four groups based on the type of composite resin used for restorations. Group 1 nanohybrid Ips Empress direct (Ivoclar Vivadent)](IPS) (13 restorations/6 patients), group 2 microfilled [Essentia (GC cooperation Japan)](ES) (14 restorations / 7 patients), group 3 supra-nano filled [ Estelite ∑ Quick (Tokuyama, Tokyo, Japan)](EQ) (17 restorations / 7 patients) and group 4 nanofill [Filtek Ultimate (3M ESPE)](FU) (13 restorations / 5 patients). Baseline Color measurements were performed with a spectrophotometer immediately after finishing and polishing (baseline), and after one year of recall, color change (ΔE) from baseline values and after one year of follow-up of DCVs were calculated according to CIELab color coordinates. For this, a silicone mold was fabricated for each patient and used as a guide for each measurement to standardize the site of the readings. Statistical analysis of the data was applied using the Kruskal-Wallis test with Dunn-Bonferroni posthoc test after controlling the distribution of data in terms of normality with the Shapiro Wilk test. Results: At the end of one year,25 participants(57restorations) were followed up. The mean ΔE of IPS, EQ, and FU composites were higher than the ES composite resin, but there was no statically significant difference between all types of composites (P> 0.05). There was no statistically significant difference in the mean ΔL* between any types of composite resin (p> 0.05). There was a significant change in Δa* and Δb* after a one-year recall for all the types of DCV restorations (p < 0.05). Conclusion: After one year of follow-up, the spectrophotometer measurements of direct resin composite veneer restorations, it was concluded no difference between the mean ΔE of ES, IPS, FU, and EQ resin composite. ES (Microfilled hybrid) showed a lower mean ΔE value compared to the other groups. All groups of resin composite showed color changes within clinically acceptable levels after a one-year follow-up.
Document clustering is the process of organizing a particular electronic corpus of documents into subgroups of similar text features. Formerly, a number of conventional algorithms had been applied to perform document clustering. There are current endeavors to enhance clustering performance by employing evolutionary algorithms. Thus, such endeavors became an emerging topic gaining more attention in recent years. The aim of this paper is to present an up-to-date and self-contained review fully devoted to document clustering via evolutionary algorithms. It firstly provides a comprehensive inspection to the document clustering model revealing its various components with its related concepts. Then it shows and analyzes the principle research wor
... Show MoreThe study includes collection of data about cholera disease from six health centers from nine locations with 2500km2 and a population of 750000individual. The average of infection for six centers during the 2000-2003 was recorded. There were 3007 cases of diarrhea diagnosed as cholera caused by Vibrio cholerae. The percentage of male infection was 14. 7% while for female were 13. 2%. The percentage of infection for children (less than one year) was 6.1%, it while for the age (1-5 years) was 6.9%and for the ages more than 5 years was 14.5%.The total percentage of the patients stayed in hospital was 7.7%(4.2%for male and 3.4%for female). The bacteria was isolated and identified from 7cases in the Central Laboratory for Health in Baghdad. In
... Show MoreThe present study cognitive aims to investigate the negation phenomenon in American political discourse under Critical Discourse Analysis (CDA) principles. The research sample includes two speeches given by Clinton and Trump in their election campaigns in 2016. Since the nature of the study follows the social-cognitive approach, the researcher adopted two models of analysis to achieve the study’s objectives: First, the theoretical framework of MST (developed by Fauconnier (1994), Fauconnier and Sweetser (1996) to examine meaning construction resulting from building different levels of negative mental spaces by two different genders the selected speeches. Second, pragmatic model to examine the role of gender from the functional per
... Show MoreThis study aims to examine how the lives of blacks are reduced and eliminated in Brother (2017) by David Chariandy. Black Lives Matter is a hash tag that appears after the killing of Trayvon Martin (17 years old African American) in 2012 by the savage hands of George Zimmerman (white person). This hash-tag has become a social movement that calls for equality in order to stop the violence against black people because their live is as valuable as white’s. The movement comes into being to highlight the “hypocritical democracy in service to the white males whose freedom are openly depended upon the oppression of blacks” (Lebron, 2017, P. 1). Those who have started this movement try to redeem a state and its arbitrary actions again
... Show MoreAlms (or Zakat) is one of the Pillar of Islam and it was atask imposed on
Muslims. Becomes of the importance of this task and its influence on the human
Psychic in particular and on the Society in general this study aims at Studying the
words that it refers to in the Holy Quran, At the beginning the researcher has
introduced the words it refers to, and the significance of each in the Holy Quran and
the Speciality of each one of such words, then the Structures they donet have been
also introduced, whether such structures are descriptive, adverbial or verbal.This was
introduced in addition to explaining the influence of changing the Shape of such
words in emphasizing the meaning and the influence of Portraiting styl
Drag reduction (DR) techniques are used to improve the flow by spare the flow energy. The applications of DR are conduits in oil pipelines, oil well operations and flood water disposal, many techniques for drag reduction are used. One of these techniques is microbubbles. In this work, reduce of drag percent occurs by using a small bubbles of air pumped in the fluid transported. Gasoil is used as liquid transporting in the pipelines and air pumped as microbubbles. This study shows that the maximum value of drag reduction is 25.11%.
The current study, performed during the period from February 2021 to June 2022 at the University of Thi- Qar/ College of Education for Pure Sciences, and aimed to follow the changes in external morphological features at different Embryonic developmental stages in pregnant rats treated with different doses of amlodipine. Usage In this study, 18 pregnant rats were randomly divided into three groups, each with six pregnant rats. Each group received different concentrations of amlodipine (0.3, 0.5) in oral doses until the 20th day of gestation, while the control group was injected with 0.9% normal saline. Teratomas are bizarre tumors derived from embryonic tissue that are normally found only in the gonadal and sacral regions of adults. Primary
... Show MoreThe research team seeks to study the phenomena of random housing in Iraqi society in general and Baghdad city in particular by standing on the causes behind this phenomena and its relation with security situation in Baghdad. The researchers adopted a theoretical and practical framework. The main objective is to diagnose the risks caused by the escalation of slums in Baghdad city.
The samples were collected monthly crustaceans Mjmafah foot of two stations in tributary Zab down and two others in the Tigris River for one year with effect from November 2001 until October 2002 recorded during the study period the current 41 units taxonomic and were higher density of Mjmafah foot Guy Tigris River before the mouth of the tributary