The objective of this study is to determine the efficacy of class V Er:YAG laser (2940 nm) cavity preparation and conventional bur cavity preparation regarding Intrapulpal temperature rise during cavity preparation in extracted human premolar teeth. Twenty non carious premolar teeth extracted for orthodontic purposes were used and class V cavity preparation was applied both buccal and lingual sides for each tooth .Samples were equally grouped into two major groups according to cavity depth (1mm and 2mm). Each major group was further subdivided into two subgroupsof ten teeth for each (twenty cavities for each subgroup). TwinlightEr:YAG laser (2940 nm) with 500mJ pulse energy, P.R.R of 10 Hz and 63.69 J/cm2 energy density was used. The analysis of the data collected revealed that there was highly significant difference between subgroups of each group, i.e., (Er:YAG laser and conventional bur cavity preparation). Also there was a highly significant difference between both group1 and group 2 subgroups (with 1mm and 2mm cavity depth). Best results were obtained from subgroup A which represents class V cavities prepared using Er:YAG laser with energy density of 63.69 J/cm2 .Er:YAG laser cavity preparation with energy density of 63.69 J/cm2 was less temperature rise than conventional bur cavity preparation taking into account the invitro temperature rise of class V cavity preparation.
Break in the bond and its impact on the difference of scholars
The study aims to test the relationship of work pressure to its dimensions (role conflict, ambiguity of role, workload and nature of work) as an independent variable and its effect on organizational alienation by its dimensions (disability, lack of power, indifference, animosity, social isolation and self-alienation) (Restraint and confidence in negation, initiative, adaptation and living conscience) as a mediator variable, in some faculties of Baghdad University of Science (Medicine and Engineering) and Humanity (Education and Literature). The data was collected on the practical side, which was applied randomly (306) of the teachers and teachers of the colleges (56) items, which included the main research variables
... Show MoreBackground: Enterococcus faecalis is emerging as an important endodontic pathogen, which can persist in the environment for extended periods after treatment and may cause endodontic failure. It is known to produce biofilms, a community of bacteria enclosed within a protective polymeric matrix. This study aimed to establish whether the biofilm formation by Enterococcus faecalis can be inhibited with steralium, co+steralium, and 5% sodium hypochlorite in the root surface environment. Materials and Methods: Extracted human teeth were biomechanically prepared, vertically sectioned, placed in the tissue culture wells exposing the root canal surface to E. faecalis to form a biofilm. At the end of the 3rd and 6th weeks, all groups were treated fo
... Show MoreThe researchers have discovered weaknesses in the rotational phase of the 100-meter freestyle event, including a lack of proper movement direction and control of biomechanical variables necessary for swimmers to achieve high rotational accuracy, which leads to outperforming competitors. The objective of this study was to investigate the effect of using a laser device on improving the performance of the rotational phase among swimmers on the Iraqi national team. The experimental approach was conducted on a sample of 6 swimmers, representing 100% of the target population. The researchers concluded that the utilization of a proposed laser device in the rotational phase resulted in positive differences in biomechanical variables, contri
... Show MoreWorldwide attention is being focused on nanocrystalline zeolites and they are replacing conventional ones due to their pronounced potential in many fields. In this study, NaY zeolite has been prepared hydrothermally using sol –gel method and modified to the proton type by ion –exchange process. Characterization is made using X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), Atomic force microscopy (AFM), Brunauer –Emmet- Teller (BET) nitrogen adsorption method, Ammonia Temperature programmed desorption (NH3-TPD) and Scanning electron microscopy( SEM). The effect of aging time, silica to alumina ratio is studied and the results sh
... Show MoreThe study seeks to examine the level of personal efficacy and its relation to mental alertness among university students. Besides, the statistically significant differences in regard of students' gender, and the correlation between male and female. To do this, the researcher adopted two scales: one to measure the personal efficacy which was made up by (abed al-jabaar, 2010) included (26) items, and the other to measure the mental alertness that designed by (abed Allah, 2012) included (36) items. A total of (120) student were selected randomly from three-different colleges at the Al-Mustansiriyah University for the academic year 2016-2017. The findings revealed there are no significant differences among students in regard of the personal
... Show MoreThe speaker identification is one of the fundamental problems in speech processing and voice modeling. The speaker identification applications include authentication in critical security systems and the accuracy of the selection. Large-scale voice recognition applications are a major challenge. Quick search in the speaker database requires fast, modern techniques and relies on artificial intelligence to achieve the desired results from the system. Many efforts are made to achieve this through the establishment of variable-based systems and the development of new methodologies for speaker identification. Speaker identification is the process of recognizing who is speaking using the characteristics extracted from the speech's waves like pi
... Show MoreSeeds, beans, leaves, fruit peel and seeds of five plants (Ferula assa-foetida, Coffea robusta, Olea europaea, Punica granatum and Vitis vinifera, respectively) were extracted with four solvents (distilled water, 80% methanol, 80% acetone and a mixed solvent that included methanol, ethanol, acetone and n-butanol at proportions 7:1:1:1). Such manipulation yielded 20 extracts, which were phytochemically analyzed for total polyphenols (TP) and flavonoids (TF). The DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity (RSA) and DPP-4 (dipeptidyl peptidase-4) relative inhibition activity (RIA) were also assessed for each extract. The results revealed that mixed solvent extract of V.
... Show MoreThe study aimed to show the concept and importance of accounting Conservatism, Persistence and volatility of earnings of companies listed in the Iraqi market for securities have been selected 35 companies for the period between 2013 to 2107 used the scale of book value to market value to measure the Conservatism while the current profit regression model was used to measure future profits Eviews 9 was used for the purpose of testing the two hypotheses. The results of the study found that there is a statistically significant relationship between accounting Conservatism and Persistence of earnings. The relationship is inverse with no statistically significant relationship between Conservatism and earnings volatility.