Background: It may be an important prospective clinical use of manufacturing of porous implant for clinical situations, such as cases of limitation in bone height, low bone density .The small segment of porous implant an effective osseointegration allows increasing in contact area provided for small segmented porous provided by its surface configuration. This study was done to Fabricate porous titanium implants by powder technology, as well as the observation of removal torque values of porous titanium implants compared to smooth titanium implants. Materials and methods: Twenty porous titanium implants (3.2mm in diameter and 8mm in length) were manufactured by powder technology using commercially pure titanium powder of ≤75um particles size, with polyvinyl alcohol powder of 212-300um particle size, as a space holder, by volume ratio (70:30) % respectively. The mixed powder was compacted using punch and die set -specially designed for this study –under 20 bar then sintering at 900 ºC by the use of argon gas. Twenty smooth titanium implants were prepared of (3.2mm in diameter and 8mm in length) by lathing of commercially pure titanium rod as a control group. The implants were examined by X-ray diffraction (XRD) and scanning electron microscope (SEM), as well as estimation of porosity percentage. For each tibia of the 20 white New Zealand rabbits, one implant of each type (one porous in right, and the smooth in left tibia), were inserted through surgical procedure carried under serial condition. Mechanical test was performed to evaluate the bone-implant interface, after (2 and 6 weeks) healing periods . Results: Porous implants were obtained successfully by powder technology with 52% porosity and pore size 210um 17±. The porous implant showed significantly higher removal torque values when compared to smooth implants at the two different intervals of examination (2,6 weeks) , this proved to be statistically highly significant, also a highly significant difference was noticed for the means of the torque removal values in the same group at different implantation , with no evidence of clinical features of inflammatory reaction with both . Conclusions: Powder technology seemed to be particularly advantageous in fabrication of porous titanium. Porous implant show an increasing bone ingrowth compared with the smooth type represented by higher removal torque for both healing periods (2, 6) weeks . Key words: Porous titanium implant, powder technology, removal torque test.
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In real conditions of structures, foundations like retaining walls, industrial machines and platforms in offshore areas are commonly subjected to eccentrically inclined loads. This type of loading significantly affects the overall stability of shallow foundations due to exposing the foundation into two components of loads (horizontal and vertical) and consequently reduces the bearing capacity.
Based on a numerical analysis performed using finite element software (Plaxis 3D Foundation), the behavior of model strip foundation rested on dry sand under the effect of eccentric inclined loads with different embedment ratios (D/B) ranging from (0-1) has been explored. The results display that, the bearing capacity of st
... Show MoreBackground: The aims of the study were to evaluate the unclean/clean root canal surface areas with a histopathological cross section view of the root canal and the isthmus and to evaluate the efficiency of instrumentation to the isthmus using different rotary instrumentation techniques. Materials and Methods:The mesial roots of thirty human mandibular molars were divided into six groups, each group was composed of five roots (10 root canals)which prepared and irrigated as: Group one A: Protaper system to size F2 and hypodermic syringe, Group one B: Protaper system to size F2 and endoactivator system, Group two A:Wave One small then primary file and hypodermic syringe, Group two B:Wave One small then primary file and endoactivator system, Gr
... Show MoreLaue back reflection patterns for quartz crystal are indexed by using Orient Express- program to simulate orientation of single crystals from assignment of principle zones. An oriented quartz single crystal was used as a substrate to deposit Zn metal by controlled thermal evaporation to achieve single crystal films of Zn that are subsequently evaluated by x-ray powder diffraction.
Background: Although various imaging modalities are available for evaluating suspicious breast lesions, ultrasound-based Shear-Wave Elastography (SWE) is an advanced, non-invasive technique complementary to grayscale sonography. This technique evaluates the elasticity of a specific tissue by applying sonic pressure to that tissue.
Objective: The aim is to assess the role of SWE in evaluating solid breast masses in correlation to histopathological study results.
Subjects and Methods: This prospective study was done in a tertiary care teaching hospital from September 2019 to August 2020. A study population of 50 women aged 18 years or above with an
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When the number of confirmed coronavirus disease cases rose in Iraq in the middle of February 2021, the Iraqi government performed a closure approach to constrain mobility and factory operations and enforce social distancing. In this research, the concentrations of air components (PM2.5, PM10, nitrogen dioxide (NO2) and ozone (O3)), which represent herein the degree of air quality index, were recorded, drawn and evaluated over central (Baghdad, the capital), northern (Kirkuk Province) and southern (Basra Province) Iraq before and during the closure. The experimental duration of this research was 6 months (from 1 January 2021 to 30 June 2021), which
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In light of the rapid changes in the business environment and the entry of administrative leaders in the challenges of the atheist and twenty- increasing competition between sectors and the desire to acquire the skills, the traditional methods are no longer viable, which requires doing evaluates performance according to a more holistic, rather than limiting the performance evaluation on the financial hub that has not longer enough alone, as well as benchmarking method that has proven successful in developed countries as a way to develop and improve products and services.
I've touched your search to the development of indicators evaluating the performance and preparation of a mechanism for making comparisons of reference between o
... Show MoreThis work investigates the effect of the gas nitriding process on the surface layer microstructure and mechanical properties for steel 37, tool steel X155CrVMo12-1 and stainless steel 316L. Nitriding was conducted at a temperature of 550 °C for 2 hours during the first stage and at 750 °C for 4 hours during the second stage. SEM and X-ray diffraction tests were performed to evaluate the microstructural features and the major phases formed after surface treatment. SEM and X-ray diffraction tests were performed to assess the microstructural features and the primary phases formed after surface treatment. The new secondary precipitates were identified as γ′-Fe4N, ε (Fe2–3N), and α-Fe, exhibiting an uneven chain-like pattern wit
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The aim: Infection with the hepatitis B virus (HBV) caused by blood transfusion is a big problem throughout the world. The aim of study is to determine the faster and more accurate methods for detection of hepatitis B infections by serological screening and PCR- amplification. Materials and methods: A total of 140528 donors were tested for HBsAg and total anti-HBc from January to October 2021 in Iraq’s National Blood Transfusion Center; however, only 100 samples with HBsAg (-) and anti-HBc (+) were collected and tested for HBV DNA using quantitative real-time PCR. Results: From 2015 to 2021, the percentage of HBsAg positive donors was 0.33 percent in 2015, 0.32 percent in 2016, 0.30 percent in 2017, 0.28 percent in 2018, 0.23 pe
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