Background: Debonding and fracture of artificial teeth from denture bases are common clinical problem, bonding of artificial teeth to heat cure acrylic and high impact heat cure acrylic denture base materials with autoclave processing method is not well known. The aim of this study was to evaluate the effect of autoclave processing method on shear bond of artificial teeth to heat cure denture base material and high impact heat cure denture base material. Materials and methods: Heat polymerized (Vertex) and high impact acrylic (Vertex) acrylic resins were used. Teeth were processed to each of the denture base materials after the application of different surface treatments. The sample (which consist of artificial tooth attached to the denture base at 45 degree) are consist of (80) artificial teeth from the same model of central incisor, they were prepared , treated and bonded to the conventional heat cured and high impact acrylic denture base material then processed. Control group (Group A 40 samples) in which acrylic resins PMMA cured by conventional water- bath processing technique (74°C for 1.5 hours then boil for 30 minutes),the group was subdivided to 20 samples heat cure acrylic and 20 samples high impact acrylic. Experimentalgroups (Group B 40 samples) in which acrylic resins was cured by autoclave at 121°C, 210KPa. For 30min.the group subdivided to 20 samples heat cure acrylic and 20 samples high impact acrylic. For each subgroup, the 20 samples were subdivided according to surface treatment into: 1-Five acrylic teeth without any surface treatment (control). 2- Five acrylic teeth with diatoric preparation (retention grooves). 3- Five acrylic teeth conditioned with thinner. 4- Five acrylic teeth with retention grooves and thinner. Results: Statistical analysis revealed that chemical and mechanical treatment of acrylic teeth improved the shear bond with heat cure and high impact acrylicalsoautoclave processing improvedthe shear bond with acrylic teeth in high impact acrylic. Conclusion: Autoclave polymerization is suggested as alternative method for processing denture base resins. Autoclave polymerization can be easily performed in laboratory conditions. In High Impact Acrylic, there were highly significant differences of autoclave processing technique compared with water bath regarding the shear bond strength with acrylic teeth.
The use of silicon carbide is increasing significantly in the fields of research and technology. Topological indices enable data gathering on algebraic graphs and provide a mathematical framework for analyzing the chemical structural characteristics. In this paper, well-known degree-based topological indices are used to analyze the chemical structures of silicon carbides. To evaluate the features of various chemical or non-chemical networks, a variety of topological indices are defined. In this paper, a new concept related to the degree of the graph called "bi-distance" is introduced, which is used to calculate all the additive as well as multiplicative degree-based indices for the isomer of silicon carbide, Si2
... Show MoreThe aesthetic contents of data visualization is one of the contemporary areas through which data scientists and designers have been able to link data to humans, and even after reaching successful attempts to model data visualization, it wasn't clear how that reveals how it contributed to choosing the aesthetic content as an input to humanize these models, so the goal of the current research is to use The analytical descriptive approach aims to identify the aesthetic contents in data visualization, which the researchers interpreted through pragmatic philosophy and Kantian philosophy, and analyze a sample of data visualization models to reveal the aesthetic entrances in them to explain how to humanize them. The two researchers reached seve
... Show MoreResearch on the role of organizational change in easing the organizational conflict focuses for being one of the important topics and relatively modern and which have a significant impact on the future of organizations, so this study was to identify the relationship and the impact of organizational change and of deportation (technological, organizational structure, human resources, the change in the task) at the organizational conflict in the Earth company link Iraq, in order to reach the goals of the research, it has been the development of a questionnaire distributed to a random sample of (100) composed employees from managers and heads of departments and the people and staff at the Earth company link Iraq, the study found: the
... Show MoreAdsorption studies were carried out to test the ability of the Iraqi rice bran (Amber type) to adsorb some metals divalent cations (Cd2+, Co2+, Cu2+, Fe2+, Ni2+, Pb2+, and Zn2+) as an alternative tool to remove these pollutants from water. The Concentrations of these ions in water were measured using flame and flamless atomic absorption spectrophotometry techniques. The applicability of the adsorption isotherm on Langmuir or Freundlisch equation were tested and found to be dependent on the type of ions. The results showed different adsorptive behavior and different capacities of the adsorption of the ions on the surface of the bran. The correlation between the amounts adsorbed and different cation parameters including (electronegativity, io
... Show MoreAfter a temporary halt to forced thghebr in different cities of Iraq this methodlogy
opeations returned directiy in the areas of political conflict on the ground which are translated
operations and forced displacement violence es they operations aimed at completing the
forced displacement that occurred after the occupation in(2003)which took an upward curve
publicly after these events and some of which are aimed at the liquidation of some provinces
than any demographic diversity of religious or sectarian or alhens and others aimed at
redemographic distribution within the province itself to produce a net sectarian zones as is the
case in Diyala Nineveh and Babylon Baghdad has the epicenter of sectarian violence and th
Oxazepine [1] is non – nomologous seven –member ring that contain two netroatoms (oxygen and nitrogen ). Meanwhile diazepine [2] contains to nitrogen atoms in seven – member ring.
Diazepam (valium) [3] is used to relive anxiety tension associated with anxiety disorder and muscle spasms (1, 2, 3
... Show MoreBackground: Molar Incisor hypomineralisation (MIH) is one of the biggest challenges with great clinical interest. Currently, the etiology of MIH remains unclear. There is no previous study concerning school children aged 7 – 9 years in Al-Najaf governorate in order to estimate the prevalence and severity of molar incisor hypomineralisation and the possible associated risk factors. This study aimed to estimate the prevalence, severity and the possible associated etiological factors of molar incisor hypomineralisation and also to study the correlation between body mass index and molar incisor hypomineralisation. Material and Methods: Across sectional study conducted at Al-Najaf Governorate. A total of 600 children were enrolled those
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