Background: Sliding mechanics is widely used during orthodontic treatment. One of the disadvantages of this mechanics is the friction generated at the bracket/archwire interface, which may reduce the amount of desired orthodontic movement obtained. The aim of the present in vitro study was to evaluate and compare the static frictional forces produced by two passive self-ligating brackets stainless-steel and hybrid and two conventional brackets stainless-steel and monocrystal ligated with stainless-steel ligature wire at two degrees of torque(zero and twenty) under dry condition. Materials and method: One hundred and sixty brackets were used in this study divided into four groups each group consisted of forty brackets these are: Two self-ligating (stainless-steel and Hybrid) while the two conventional types are the (stainless-steel and monocrystal).twenty of each group examined with 0.016"x0.022"archwire, ten at 0? torque and ten at 20? torque while the other twenty of each group examined with 0.019"x0.025", ten at 0? torque and ten at 20? torque. Results: There was a significant different between all groups except in case when self-ligating brackets (both types) ligated to both wires at 0?torque there was no significant difference. Conclusions: The self- ligating brackets produce significantly lower static friction than the conventional types at both degrees of torque. There was no significant different between both self-ligating brackets at0?torque while at 20? torque the stainless- steel self –ligating produce lower static friction than the clear self-ligating type.
Background: the oral cavity is consider to be an open ecosystem, with the balance between the microorganism’s entrance and the defenses of the host. The initiation of periodontitis has been associated with restricted kinds of anaerobic bacteria, such as Aggregatibacter actinomycetemcomitans (A.a) and Porphyromonas gingivalis (P.g) in plaque subgingivally. Ozone has a biological effects on bacteria due to oxidation of bio-molecules and its toxins. The aim is to determine and compare the antimicrobial effect of gaseous ozone and ozonized water on the growth of isolated anaerobic bacteria (A.a and P.g) when exposed to different time intervals. Materials and methods:This experiment is done byozone generator OLYMPIC- III(600mg/hr) to gene
... Show MoreBackground: Esthetic correction represents one of the clinical conditions that required the use of laminate veneers in premolars region. Aim of the study: The purpose of this study was to evaluate the fracture strength of the laminate veneers in maxillary first premolars, fabricated from either composite (direct and indirect techniques) or ceramic CAD/CAM blocks. Materials and Methods: Fifty sound human maxillary premolar teeth were used in this in vitro study. Teeth were divided randomly into one control group and four experimental groups of ten teeth each; Group A: Restored with direct composite veneer (Filtek Z250 XT), Group B: Restored with indirect composite veneers (Filtek Z250 XT), Group C: Restored with lithium disilicate ceramic CA
... Show MoreThis study was aimed to conduct one of the vertical garden systems , selecting suitable plant species that with stand the climate conditions of Baghdad city in outer space to determine the appropriate growing medium for the (LWS), and to assess the impact of spraying with potassium silicate on the resistance of the cultivated plants to heat stresses . The study carried out at at Al-Batool Park of (Al-Kadhimiya Holy City). Two experiments were carried out, each one with a different plant species, including Wedelia trilobata and Tradescantia pallida, during the winter season of 2021 and summer season of 2022. The experiments were designed using a split block design. The experiments included two factors, the first being the growing med
... Show MoreA total of 33 Iraq male positive for Toxoplasmosis and Iraq male negative for Toxoplasmosis (controls) were studies to Evaluation of some biochemical and immunological parameters changes.The parameters included lipid profile such as (Cholesterol(C), Triglycerides(TG), High-Density Lipoprotein (HDL), Low-Density Lipoprotein (LDL) and very Low-Density Lipoprotein (VLDL) and complement component C3 and C4. The results revealed significant decrease in the total cholesterol, Triglycerides, LDL and non-significant in vLDL (129.96±1.63, 130.69± 2.80, 87.19±1.97, 29.24± 0.83 mg/dl respectively) and non-significant increase in HDL(24.22 ±0.62) mg/dl compared with control group(152.07± 1.63, 156.48± 6.55, 99.26 ±1.39, 31.49± 1.30 and 21.31±
... Show MoreA roundabout is a highway engineering concept meant to calm traffic, increase safety, reduce stop-and-go travel, reduce accidents and congestion, and decrease traffic delays. It is circular and facilitates one-way traffic flow around a central point. The first part of this study evaluated the principles and methods used to compare the capacity methods of roundabouts with different traffic conditions and geometric configurations. These methods include gap acceptance, empirical, and simulation software methods. Previous studies mentioned in this research used various methods and other new models developed by several researchers. However, this paper's main aim is to compare different roundabout capacity models for acceptabl
... Show MoreThis research dealt with the process of reducing costs through some strategic methods of management accounting targeted cost analysis unassembled and Alkeisen, where he focused this research through his theory on a review of some administrative accounting strategic technologies, while the second practical side through the application of targeted cost analysis unassembled and Alkeisen, acquired Search importance of focusing on the decisions to cut costs, through the use of some administrative accounting strategic methods and this we can unassembled analysis, continuous improvement, and the cost of quality) when applied quality, "in light of this has been reached to a set of conclusions that the most important of the company's relian
... Show MoreSome of the main challenges in developing an effective network-based intrusion detection system (IDS) include analyzing large network traffic volumes and realizing the decision boundaries between normal and abnormal behaviors. Deploying feature selection together with efficient classifiers in the detection system can overcome these problems. Feature selection finds the most relevant features, thus reduces the dimensionality and complexity to analyze the network traffic. Moreover, using the most relevant features to build the predictive model, reduces the complexity of the developed model, thus reducing the building classifier model time and consequently improves the detection performance. In this study, two different sets of select
... Show MoreVitamin K-dependent protein (VKDP) contributes to the development of lung cancer. The purpose of this research was to better understanding of the role of blood matrix Gla protein (MGP), VKDPs, Malondialdehyde (MDA), Superoxide dismutase (SOD) and Vitamin K (Vit K) in Iraqi patients with lung cancer before and after the first cycle of chemotherapy. Blood samples were collected from Al amal National Hospital for cancer treatment from October 2021 to May 2022, and a total of 80 samples were collected, divided into two groups (40 patient before taking a chemotherapy and 40 patients after taking chemotherapy), ranging in age from 20 to 45 years old. The results showed that although there were highly statistically significant differences in MD
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