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 research aims to show the dimensions of organizational trust represented by (administrative policies opportunities for innovation and self innovation and self- realization,availability of information,prevailing organizational values) and its reiationship to achieving the strategic position of banks represented by formation of expectations,buiiding networks,learning operations As the research was applied in each of the banks (middle east)Iraqi investment,Al-Ahly Iraqi, Business Bay, Al- Mansour investment bank),the qusestionnaire was adopted as a tool to collect data and information from the sample number (138)who are in the site (department director, division ,M.division director ,division officer, unit officer)the statistica
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The Central Bank is the backbone of the banking system as a whole, and in order to maintain the banking system, one of the most important functions that the Central Bank performs is the function of supervising and controlling banks, with several tools and methods, and one of the most important of these tools is its creation of the function of a compliance observer, which obligated commercial banks to appoint a person in A bank that performs this function according to certain conditions and granting it some powers that would build a sound and compliant banking system. The function of the compliance observer is to follow up on the bank’s compliance with the instructions and decisions issued by
... Show MoreThe present research aims to test the effect of cognitive complexity as an independent variable in organizational agility as a responsive variable among the leaders working at the headquarters of the Iraqi Petroleum Products Distribution Company.
To conclude a number of recommendations that contribute in the organizational agility in the company, and due to the importance of this research in public organizations and its notable role in community organizations. The research was carried out on a random sample of 101 individuals out of a total of 308, which represents the high leaders in the company (general managers, head of departments, and division officials). A questionnaire was used as information
... Show MoreThe Southern Cowpea Beetle Callosobruchus maculatus (F.) is one of the most widespread insect pests of stored legumes, causing a considerable loss during storage, decreasing the net weight of the crops, and resulting in reduced the quality of the crops. This study has been conducted to determine the lifetime, fertility and life table parameters of C. maculatus by using an alkaloids extract from Moringa oleifera leaves at different concentrations 1000, 2000, and 3000 ppm. The result was shown that the lowest survival rate was 49% at a concentration of 1000, 2000 ppm, as compared with the control which was 77%. The lowest reproductive rate (Ro) was 4.76 female/female/generation at the concentration of 1000 ppm, c
... Show MoreThe issue of nuclear proliferation is one of the most vital issues as it reflects a form of dealing in the field of international relations. Therefore, the Middle East region has taken great interest in reducing the levels of nuclear armament and acquiring nuclear power within the strategic framework of the international and regional powers. The establishment of a nuclear-weapon-free zone in the Middle East region is currently one of the most important international and regional arrangements for controlling the levels of nuclear proliferation and attempting to build a state of stability and balance. In the Middle East and the world. The importance of the research comes from the fact that it deals with an important and vital issue
... Show MoreEruca sativa, commonly known as rocket salad, is a popular vegetable to which a wide range of health benefits are attributed. This study aimed to examine the effects of the aqueous extract of E. sativa leaves on lipid profile and some minerals, such as calcium and magnesium, in blood of male albino mice under normal physiological condition. Two experiments were separately conducted, each with eighteen male albino mice divided into 3 equal groups, which included control, treated group (1), and treated group (2) which were orally administrated with 0, 0.2 and 0.4 mg/kg body weight, respectively, of the leaves extract for 28 days. In the first experiment, serum lipid profile, including cholesterol, triglyceride, HDL, LDL a
... Show MoreThe research aims to know the concept of politic behavior as one of the important behaviours in the different fields and sectors. It is considered to be part of the organizatial work to face the expected risks. It includes two group of factors personal (self –monitors, locus of control ,expectation s of success, perceived job alternatives)and organizational(promotion ,division resources,role ambiguity ,democratic decision)studied by the researcher in the frame of the relationship with the variable of display continuous trust matain which includes two variable (build trust mantain, display trust continuouness)through applied frame by random sample consists of (90)employee at Farouq State
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