Background/: Buccal tubes are orthodontic attachments used on the posterior teeth instead of bands, so it is important to focus on the effect of their properties on orthodontic treatment. The aims of the present in vitro study are to evaluate and compare the buccal tube front and back openings dimensions and the torsional play angle of six different brands. Materials and Methods: The samples consisted of Single bondable, non-convertible first molar buccal tubes from six brands supplied from six companies (Dentaurum, Forestadent, Ormco, 3M, American Orthodontic, A-Star). Regarding tube opening dimension, ten buccal tubes of each brand were examined by an optical microscope. Each tube was fixed during examination using synthetic mud and oriented for observation of the front and back slot openings. A picture was taken for both tube openings and the result appeared on the computer's screen where width and height measurements were made. While regarding torsional play angle, ten buccal tubes of each brand were used. Each tube was fixed on a metal block attached to a surveyor base. Then an L-shaped wire was inserted inside the front opening of the tube. Two photographs were taken, one with the wire in free fall position and the other with the wire elevated by a 10g weight with the same angle of shooting as the first photograph. Later, the two images were superimposed in Adobe Photoshop program, and an electronic MB-ruler Software was used to calculate the angle which represents the torsional play within each tube. The data were then statistically analyzed using ANOVA and LSD tests. Results: There are marked differences between measured tube dimensions and the manufacturer stated dimensions with the front tube openings being generally larger than the back opening dimensions. Furthermore, the torsional play angle was highest in A-Star and smallest in Ormco's tubes. This angle was significantly correlated to the height of the tube front opening. Conclusion: It can be concluded that tube dimension varies among different companies and effect greatly torsional play angle.
The objective of present study was to investigate the effect of using mixture volaticle oil of rosmarinus and nigella sativa to improve some of the meat quality characteristics, physical and limited storage time of minced cold poultry meat. Duplex volaticle oil was added at 0.025, 0.050 and 0.075 g/kg to minced poultry meat, these treatments were stored individually for 0 , 4 and 7 days at 4-7C0. After making several chemical, physical and oxidation indicators, the following results were obtained:
The process of adding volaticle oil to minced poultry meat led to significant increase (P<0.01)in moisture, prot
... Show MoreTo develop a petrol engine so that it works under the bi-engine pattern (producer gas-petrol) without any additional engine modifications, a single-point injection method inside the intake manifold is a simple and inexpensive method. Still, it leads to poor mixing performance between the air and producer gas. This deficiency can cause unsatisfactory engine performance and high exhaust emissions. In order to improve the mixing inside the intake manifold, nine separate cases were modelled to evaluate the impact of the position and angle orientation inside the intake manifold on the uniformity and spread of the mixture under AFR=2.07. A petrol engine (1.6 L), the maximum engine speed (8000 rpm), and bi-engine mode (petrol-producer ga
... Show MoreThe study aimed to prepare a set of qualifying exercises to improve the muscular strength of the muscles surrounding the ankle joint by applying different resistances according to the nature of the movement of this joint, which is one of the second moving joints (flexion, extension and rotation of the right and left) in order to increase the efficiency of all muscles working on this joint according to those movements and identification On the impact of these exercises and assume that there will be statistical differences between the two tests of the research sample. The researcher used the semi-articulated experimental method with a pre- and post-test for one group. The injury was evaluated on the women's national team players durin
... Show MoreUltraviolet spectrophotometric studies for antibiotic (amino glycoside) derivatives including, Neomycin, Streptomycin, Gentamycin and Kanamycin with special reagents, which are benzoyl chloride; benzene sulfonyl chloride, toluenesulfonyl chloride and phthalic anhydride were made. Amino glycosides derivatives were followed through measurements of the ultraviolet absorbance (A) from which the absorptivity (ε) of the complexes was deduced and molar absorbances using Ultraviolet for products and calculate the number of reagents molecule that combine to amino glycosides.
Background: Dental caries is one of the most significant problems in world health care. Restoring carious primary teeth is one of the major treatment goals for Children, and the light activated resin restoration materials like composite, resin-modified glass ionomer and polyacid-modified which was introduced in dentistry in 1970, widely used in clinical dentistry but its application increased dramatically in recent years because of its biocompatibility, color matching, good adhesive properties of its resemblance in physical and mechanical aspects to tooth. The aim of this study: To evaluate the microleakage of Polyacid-Modified Composite resin Compared to Flowable Hybrid Composite and Resin-Modified Glass ionomer cement. Materials and me
... Show MoreIn their cross-sectional study, Al-Rubaye et al studied the extent of vitamin D (VD) deficiency/ insufficiency, factors affecting its degree, and the adverse outcomes of the altered VD status among a group of mothers and their neonates from Baghdad, Iraq. They found that 96.6% of the mothers had VD deficiency/ insufficiency compared to 86.4% in their neonates. Maternal VD levels and neonatal weights were significantly correlated with neonatal VD levels. We believe that the study results need to be revised. This is based two points listed in this letter to editor
Background: The most common reason for re-making a maxillofacial prosthesis is the degradation of the mechanical properties of the silicone. Aim of this study: To assess some mechanical properties of VST-50F maxillofacial silicone reinforced with a composite of silicon dioxide nanoparticle and polyamide-6 microparticle before and after artificial aging. Material and Method: Preparing 240 samples tested for tear strength, tensile strength and elongation percentage, hardness, and roughness before and after aging. The Silicon dioxide was added in concentrations of 1% by weight and Polyamide-6 in the concentration of 0.25% and 0.5% by weight to the VST-50F RTV maxillofacial silicone. The one-way ANOVA and post hoc tests were used for inferentia
... Show MoreThe current research seeks to achieve several objectives, including knowing the extent of the audit directorate of the Ministry of Construction, Housing and General Municipalities of the International Standard (ISO19011:2018) regarding determining the efficiency and evaluation of auditors and diagnosing the gap between requirements and application and knowing the reasons for not applying some of the items in the standard, starting from the problem, The field raised the following question (Does the audit directorate determine the efficiency and evaluation of auditors according to the standard ISO19011:2018?), and the importance of research lies in determining the return that can be achieved by the directorate through its application of stand
... Show MoreThe purpose of this paper is to identifying the values of some physical and Bio- Kinematic variables during the performance of the jump spike serve skill, and identifying the effect of the proposed training program using intermittent training to develop some physical and Bio- Kinematic variables and accuracy of the jump spike serve skill among the research sample. The experimental method was used and the research was conducted on a deliberately chosen sample of the players of the Army Club, who were primarily advanced in volleyball, and the number of the sample was (10) players. The conclusions were reached that the proposed training program using intermittent training has a positive effect on some of the physical and Bio- Kinematic variabl
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