Background: Lack of durability of the bond of the dental adhesive systems to tooth structure is one of the most important problems in tooth colored restorative work. This in vitro study was performed to evaluate the effect of 2% chlorhexidine gluconate(CHX) on dentin bond strength by using total etch adhesive system at twenty-four hours and three months of water storage. Material and methods:A flat dentin surface was prepared for forty sound human maxillary premolar teeth which were acid etched with 36% phosphoric acid gel after being divided randomly into four groups of ten teeth each according to storage time and CHX application, theCHX was applied for 60 seconds before adhesive application for groups I and III which were tested after twenty-four hours and three months respectively, while the distal water was applied for 60 seconds before the application of adhesive for group II and IV which were tested after twenty-four hours and three months respectively.The Prime and Bond® NT™ adhesive (Dentsply) was applied and cured, Composite (Ceram X mono, Dentisply) was applied through special mold with 2 mm thickness and light cured, Then all specimens were stored in distilled water 37oC until the time of testing of each group.Shear bond strength test was performed at the end of the storage period (24 hours or 3 months). Results:T-test results showed high statistically significant reduction in shear bond strength (SBS) in non CHX group IV (tested after 3 months) compared to non CHX group II (tested after 24 hours)(P< 0.01). In CHX groups I (tested after 24 hours) and III (tested after 3 months), results showed no statistically significant differences in shear bond strength(p> 0.05).On the other hand result showed statistically no significant differences between groups I and II in 24 hours shear bond strength (P> 0.05). After 3 months water storage, there was statistically high significant differences between the groups III and IV (P< 0.01). Conclusion: the use of 2 % CHX glocounate solution after acid etching and before bonding of dentin have no adverse effect on immediate bond strength (24 hours storage), and was effective in reducing degradation of resin-dentin bond interface after three months of water storage.
A new series of chalcone derivatives featuring an oxadiazole-quinoline moiety were successfully synthesized through a multi-step reaction sequence, commencing with quinoline-2-carboxylic acid as the starting material. First, the carboxylic group was chlorinated to form an acid chloride, following reacted with hydrazine hydrate. The resulting product underwent cyclization with carbon disulfide in an alkaline solution to produce 5-(quinolin-2-yl)-1,3,4-oxadiazole-2-thiol, followed by alkylation using chloroacetone. In the final step, an aldol condensation reaction was carried out by grinding the acetone derivative with various aromatic aldehydes, yielding the desired chalcones. The synthesized compounds were characterized by Rf, FTIR,
... Show More
The Historical effect of Conflict between North and South
The organizational culture is an effective control mechanism that dictates the behavior of employees and according to their intellectual and social orientations, so it is considered a more powerful way to control employee orientations and determine their management according to organizational rules and regulations, as it was one of the most important factors determining the performance of organizations, while organizational performance is a measure of what the organization has achieved from the objectives of the scheme To ensure that it faces various changes and remains within the global competition, and to reach that it was necessary to identify the most prominent and most important research problems in knowing the extent of com
... Show More
(1)
Human interferon as is the case in all kinds of interferon has complex effects but all share their impact on preventing the proliferation of viruses and preventing or reducing human Alantervjørn conversion occurs if the cell is in preventing the growth of the virus when interferon Balnmstqubl connects
This research aims to:
1 – Make a proposed module for (aesthetics) for the second stage - Department of Art Education under education theories.
2 - Verification from the effect of the proposed module on student achievement and motivation towards learning aesthetics material.
To verification the second goal we wording these two hypotheses:
1- There are no individual differences with statistically significant at level (0.05) between the student's scores average. (Experimental group ) who studied according to the proposed module and the average student's scores (control group) who studied in the usual way for the achievement test for the Aesthetics material.
2- There are no individual differences with statistically signifi
Objective(s): To determine the effect of obesity and socioeconomic status upon adolescents' high school students' intelligence quotient in Baghdad City. Methodology: A descriptive design is carried throughout the study to determine the effect of obesity and socioeconomic status on adolescents' high schools students' intelligence quotient in Baghdad City for the period of January 7th 2017 to May 29th 2017. A non-probability, purposive sample, of (120) high school students, is selected. The sample is comprised of (12) students from 7th grade, (26) students from 8 th grade, (14) students from 9th grade, (3
In this study forty mature albino rats were used wich were randomly divided into five groups ,four groups were adminstrated Phoenix dactylifera pollen grains suspension at concertenrations (18,54,108,and 216)mg/ kg body weight by oral administration while the fifth group was considered as a control group.Experiment continued for 40 days then rats were sacrificed and samples of blood were collected for determination of some biochemical parameters (total protein ,total cholesterol ,LDLc and HDLc).Testis were removed for preparation histological sections to measures the diameters of seminferous tubules ,thickness of seminiferous epithelium and the numbers of spermatogenic cells.
... Show More
Pregnancy and childbirth are physiological states characterized by sudden hormonal and immunologically described changes. The current study aimed to investigate the influence of maternal variables (age, previous abortion, placental position, and fetal position) on some physiological biomarkers, such as oxytocin (OT), prolactin (PRL), cortisol, and insulin growth factor 2 (IGF -2) and some immune biomarkers such as programmed cell death protein 1 (PD-1), programmed cell death ligand 1 (PD-L1) and interleukin 6 (IL-6) in Iraqi women undergoing caesarean section (CS). Blood samples were collected from 48 pregnant women in the age range (16-43 years) and serum was obtained to determine the levels of the above biomarkers. The effect of
... Show More
(3)