Background: Separation and deboning of artificial teeth from denture bases present a major clinical and labortory problem which affect both the patient and the dentist. The optimal bond strength of artificial teeth with denture base reinforced with nanofillers and flexible denture bases and the effect of thermo cycling should be evaluated. This study was conducted to evaluate and compare the shear bond strength of artificial teeth (acrylic and porcelain) with denture bases reinforced by 5% Zirconium oxide nanofillers and flexible bases under the effect of different surface treatments and thermo cycling and comparing the results with conventional water bath cured denture bases. Material and methods: Two types of artificial teeth; acrylic and porcelain were used and prepared for this study. Five specimens of each tooth type were processed to each denture base materials after the application of different surface treatments; these teeth were bonded to heat polymerized, nano composite resin and flexible denture bases. Specimens were thermo cycled and tested for bond strength until fracture with an Instron universal testing machine. Data were analyzed with analysis of variance and student T-test. Photomicrographic examinations were used to identify adhesive and cohesive failures within debonded specimens. Results: The mean force required to fracture the specimens were obviously larger for nanocomposite specimens compared with the heat cured and flexible specimens. The most common failure was cohesive within the tooth or the denture base. With each base material, the artificial teeth which were treated with thinner exhibited highest shear bond strength. Thermocycling had deleterious effect on the flexible denture base specimens. In general, nanocomposite and heat cured groups failed cohesively within the artificial tooth. While the valplastic groups failed adhesively at the tooth denture base interface. Conclusions: Within the limitations of this study, the type of denture base materials and surface treatments of the tooth selected for use may influence the shear bond strength of the tooth to the base. Selection of more compatible combinations of base and artificial teeth may reduce the number of prosthesis fractures and resultant repairs. Key words: acrylic teeth, porcelain teeth, Nano composite denture base, thermo cycling, flexible denture, thinner,
The current study has beenconduced to evaluate the effect of extracted crude terpens at the concentrations of 6,8% of seeds of Eucalyptuscamaldulensison the 4th larval instar oftheCallosobruchusmaculates and the percentage of the cowpea seed germination.The Results showed that the terpens extract of the concentration of 8% increases the mortality rate of the fourth larval instar and it reach to 63.3%, and then decrease of to 26.6,20% at concentration of 6%and forcontrol treatment respectively The percentage of adult emergence reduces to 0% at the concentration of 8% compared with control treatment in which it reach to 66.6%. The extraction atbothconcentrations 6,8% does not affect the germination rate
Corruption has become the subject of great interest, and the subject of research and scrutiny in recent years, because of its penetration in all fields of life, whether these fields are political, economic, social, and administrative. It is one of the biggest challenges and problems that are facing communities. Therefore, this study is focused on the evaluation of measures implementing the national strategy to combat corruption in Iraq.
This study was launched, first because of its intellectual dimensions to ensure a conceptual presentation of the strategy and operational management in general with a special focus on the processes of implementation and control str
... Show MoreThe aim of the study is to prepare a measure of the role of academic coaches in handball skill performance from the point of view of the researchers. The researchers used the descriptive approach in the research procedures as it is an appropriate approach in achieving the research objectives. The next question is: To what extent will the players benefit from the academic coach in developing their skill performance? This is the measure of the role of academic coaches. From 16 items, the research community included players (Al-Karkh Club - Al-Hashd Sports Club) and the number of players was (Al-Karkh 14 - Al-Hashd 14). The research sample was intentional and represented (the research community 100% The researchers concluded that measuring the
... Show MoreThe research aims at introducing the principles of six sigma and if it had any effect of the dimensions of six sigma to improve the performance of the dentists and the availability of an appropriate environment in the center Specialist respondent to the application of six sigma principles and how to adopt Specialized Center under the dimensions of the six sigma and if there informed enough with the management methodology six sigma, and if you can adopt six sigma as one of the entrances to reduce medical errors. So Search creating six sigma five dimensions and are (the commitment and support of senior management, the focus on the patient, continuous improvement, training and civil, and infrastructure) as a variable int
... Show MoreThe present study include a new developed method of analysis for determination of drug Spironolaction (SP) in some Pharmaceuticals by Spectrofluorometric method. Spironolaction was determined under optimal experimental condition that follows :- The excitation spectrum was (l=351 nm), the emmetion spectrum was (l=518 nm), pH=1, the suitable temperature for reaction 60oC and the optimal time less than (3) minute. The analysis and rang statistical data was:-Linear dynamic rang (1-10) ?g.ml-1, the detection limit (D.L = 0.023 ?g.ml-1), Molar absorptivity (? = 29875 liter mole-1 cm-1), Relative standard deviation (%RSD = 0.78), (%Erel = 3.3) and recovery (Rec = 96.6) percentage. Determination of Spironolactone was accomplished by two methods
... Show MoreThe research studies the synthetic sculpture techniques in the outputs of the students of the department of art education in terms of the shape, texture, content and technique, and employing this style by the students of the department of art education on the college of fine arts, university of Diyala. The research consists of four chapters: the first chapter: the research problem summarized by looking for the synthetic sculpture and its importance in the treatment the industrial wastes in our social life, according to modern synthetic techniques, in the American and European sculpture. This technique has been employed in more than one contemporary artistic direction and style.
This study is considered important for the students of t
Collapsing building structures during recent earthquakes, especially in Northern and Eastern Kurdistan, including the 2003 earthquake in Cewlig; the 2011 earthquake in Van; and the 2017 earthquake near Halabja province, has raised several concerns about the safety of pre-seismic code buildings and emergency facilities in Erbil city. The seismic vulnerability assessment of the hospital buildings as emergency facilities is one of the necessities which have a critical role in the recovery period following earthquakes. This research aims to study in detail and to extend the present knowledge about the seismic vulnerability of the Rizgary public hospital building in Erbil city, which was constructed before releasing the seism
... Show MoreBackground: Radiologic evaluation of breast lesions is being achieved through several imaging modalities. Mammography has an established role in breast cancer screening and diagnosis. Still however, it shows some limitations particulary in dense breast.
Methods : Magnetic resonance imaging is an attractive tool for the diagnosis of breast tumors1 and the use of magnetic resonance imaging of the breast is rapidly increasing as this technique becomes more widely available.1 As an adjunct to mammography and ultrasound, MRI can be a valuable addition to the work-up of a breast abnormality. MRI has the advantages of providing a three-dimensional view of the breast, performing wit
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