Stereo lithography (SLA) three-dimensional (3D) printing process is a type of additive manufacturing techniques that uses digital models from computer-aided design to automatically produce customized 3D objects. Around 30 years, it has been widely utilized in the manufacturing, design, engineering, industrial sectors and its applications in dentistry for manufacturing prosthodontics are very important. The stereo lithography technology is highly regarded because it can produce items with excellent precision especially when selecting the best process parameters. This review article offers a useful and scientific summary of SLA three-dimensional printing technology and its brief history. The specific type of 3D printers which is SLA type based on light curing resin and material overview is also presented. Moreover, the survey was conducted to gain substantial knowledge of the various advantages and disadvantages of SLA 3D printing. According to this study, a summary has been specified on the accuracy of SLA 3D printers and various factors that affected its accuracy and dimension measurement namely layer thickness, normal exposure time, bottom or top exposure time, post processing and room temperature. The majority of works in the literatures conducted till date are on improving the physical part attributes like dimensional accuracy and surface roughness but the improving of the mechanical properties have received less attention and need more focusing in the future works.
Background: Irrigation of the canal system permits removal of residual tissue in the canal anatomy that cannot be reached by instrumentation of the main canals so the aim of this study was to compare and evaluate the efficiency of conventional irrigation system, endoactivator sonic irrigation system,P5 Newtron Satelec passive ultrasonic irrigation and Endovac irrigation system in removing of dentin debris at three levels of root canals and to compare the percentage of dentin debris among the three levels for each irrigation system. Materials and methods: Forty extracted premolars with approximately straight single root canals were randomly distributed into 4 tested groups of 10 teeth each. All canals were prepared with Protaper Universal ha
... Show MoreThis research a study model of linear regression problem of autocorrelation of random error is spread when a normal distribution as used in linear regression analysis for relationship between variables and through this relationship can predict the value of a variable with the values of other variables, and was comparing methods (method of least squares, method of the average un-weighted, Thiel method and Laplace method) using the mean square error (MSE) boxes and simulation and the study included fore sizes of samples (15, 30, 60, 100). The results showed that the least-squares method is best, applying the fore methods of buckwheat production data and the cultivated area of the provinces of Iraq for years (2010), (2011), (2012),
... Show MoreVitamin D is a fat-soluble vitamin with antioxidant and DNA protecting properties , Levofloxacin is a member of the fluoroquinolone drug class, Its broad-spectrum bactericidal effect affects both Gram-positive and Gram-negative bacteria.
The goal of the study is to analyze the haematology analysis in rats received levofloxacin and show the preventive impact of vitamin D3 by analyzing the haematology parameters: packed cell volume (PCV), mean corpuscular hemoglobin concentration(MCHC),haemoglobin (HB), red blood cell (RBC), mean corpuscular volume (MCV),meancorpuscular haemoglobin(MCH), WBC ,differential WBC, and Platelets.
The study included 42 rats divided into 6 groups each group 7 rats. group I negative control
... Show MoreAs asphalt concrete wearing course (ACWC) is the top layer in the pavement structure, the material should be able to sustain stresses caused by direct traffic loading. The objective of this study is to evaluate the influence of aggregate gradation and mineral filler type on Marshall Properties. A detailed laboratory study is carried out by preparing asphalt mixtures specimens using locally available materials including asphalt binder (40-50) penetration grade, two types of aggregate gradation representing SCRB and ROAD NOTE 31 specifications and two types of mineral filler including limestone dust and coal fly ash. Four types of mixtures were prepared and tested. The first type included SCRB specification and
... Show MoreAbrus precatorius L. is an important medicinal plant belonging to family Fabaceae. The present study was conducted to perform pre-clinical safety evaluation and study the pharmacological effects of the ethanolic seeds extract of A. precatorius in management of pain, psychiatric and neurological conditions. Acute toxicity was performed to study the general behavioural pattern of mice after treatment with the test extract (single doses of 1000, 2000, 3000,4000,5000 mg/kg, body weight) and sub-acute toxicity studies were performed to study the toxic effects of the test extract (1000,2000,3000 mg/kg, per os for 14 days) on different haematological parameters, body and organ weight and histopathology of liver and kidney. The toxicological evalua
... Show MoreTests were performed on asphalt concrete specimens with (101.6 mm in diameter and 101.6 mm in height), and the results were implemented for calculating permanent deformation and resilient modulus under repeated compressive stress with different levels of stresses (0.068, 0.138 and 0.206) MPa at 40 ºC. Two types of additives namely (carbon black-asphalt) and (SBR-asphalt) were tried as rejuvenators with three percentages of (0.5, 1 and 1.5) % by weight of asphalt cement along with two ratios of AC (1 and 2) % have been implemented as rejuvenator and blended with the reclaimed asphalt concrete. Aged materials were obtained from the site. 100% Reclaimed Asphalt Pavement material from the reclaimed mixture is implemented. A
... Show MoreThat any industrial company that must think about marketing mechanisms and who are the beneficiaries and the pursuit of gain customer satisfaction with access to competitive advantages. Most industrialized our companies from a variety of problems experienced both in the field of production, marketing, or keep up with new developments or commitment to quality standards, which caused the reluctance of customers to buy local products for various reasons, and especially in light of unplanned economic policy and exposure to market to imported products flooding the market with various goods and services that do not can the domestic industry rival, which has competitive advantages and meet business requirements, but others arrived to stop or as
... Show MoreThis research aims to clarify the role of Information Technology Competency (ITC) with dimensions' (IT Usage, IT Knowledge, and IT Operations) as an independent variable in the activation of Human Resources Management Practices (HRM Practices) as a dependent variable with dimensions' (Training and Development, Recruitment, Job Design, and Performance appraisal). Based on this, the correlation and effect relationships between the independent and dependent variables are determined by formulating two main hypotheses. There are a significant relationship and effect of IT competency with HRM practices within the dimensions. Furthermore, the scope and population of this research are the Informatics and Communications P
... Show MoreThe aim of the research is to identify the role of public relations in promoting tourism by the Palestinian tourism and travel companies in Gaza from the public relations officer’s point of view in those companies.
The researcher used the descriptive analytical method as the most appropriate for such studies and implemented the questionnaire as a tool to obtain the required data from the respondents.
The Researcher reached several conclusions:
1- There is a low percentage of women working in the field of public relations in Palestinian tourism establishments in the Gaza Strip, where the percentage did not exceed 5%.
2- The interpersonal communication counted as one of the elements of integra