Abstract: Recombinant human bone morphogenetic protein-2 (rhBMP-2) and platelet-rich fibrin (PRF) bioactive materials have been used to enhance healing and improve dental implant stability. This study aimed to compare the effect of rhBMP-2 and PRF bioactive materials on dental implant stability at different intervals and to evaluate the correlation of implant length and diameter with implant stability. Two bioactive materials were compared to evaluate their effect on dental implant stability. A total of 32 patients (102 dental implants) were divided into 3 groups: 24 dental implants with bone morphogenetic protein (BMP), 27 dental implants with PRF, and 51 dental implants without BMP or PRF (control group). Data were statistically analyzed to determine the bioactive material with the best effect on implant stability. Implant stability did not significantly differ between the groups immediately after implant insertion (first reading; P>0.05). The implant stability of the rhBMP-2 group was significantly better than those of the PRF and control groups 6 weeks after implant insertion (second reading; P¼0.001). After 12 weeks, the effect of rhBMP-2 on implant stability was highly significant and better than that of the other groups (third reading; P<0.001). Dental implants coated with BMP have a better effect on stability than those with PRF alone and those without PRF or BMP.
Polymer matrix composites are suitable materials for medical applications, such as denture base resin polymethyl methacrylate (PMMA). This includes light weight and high strength. This paper describes the effect of selected weight fractions (1, 2, 3, 4 & 5) % wt of nano(Alumina AL2O3, Zirconia ZrO2, Hydroxyapatite HA and Halloysite nanoClay) reinforcements on the biopolymer matrix (PMMA). Some tribology tests were used to evaluate the prepared system (impact strength, hardness surface, and wear rate) tests. The samples were fabricated by (Hand Lay-Up) with different particle reinforcement percentages. All tests were accomplished at room temperature, and samples were developed according to the ASTM standard. The weight fraction o
... Show MoreVariation orders are an on-going phenomenon in construction and industry projects worldwide, particularly in the province of Sulaimani, where the project's damage from cost and schedule overrun because of variation orders. However, the effect on project costs and time overrun of variation order has yet to be identified. This study evaluates the impact of variation orders on the cost and time off in the Sulaimani governorate. Two hundred twenty-eight projects from various construction sectors built between 2007-2012 were adopted to calculate the contract cost and schedule overruns due to variation orders. Data analysis was applied in the study were descriptive statistics. One-way ANOVA was also applied to determine w
... Show MoreThe global rise in temperature and the desert climatic conditions prevalent in Middle Eastern countries have exacerbated rutting distress in heavily trafficked highways. Conventional asphalt binders with a high-temperature performance grade (PG 70) have proven inadequate under such extreme conditions, necessitating the development of modified binders with enhanced high-temperature performance. While polymer modification using styrene-butadiene-styrene (SBS), an elastomeric polymer, and ethylene-vinyl acetate (EVA), a plastomeric polymer, has been widely studied, limited research provides a direct comparison of their effectiveness at both the binder and mixture levels under extremely high-temperature conditions. This study addresses this gap
... Show MoreConstruction projects have a special nature and affect them many factors making them exposed to multiple risks as a result of the length of the implementation period and the multiplicity of stages, starting from the decision stage through implementation until the final delivery, which leads to increased uncertainty and the likelihood of risk.
The process of analysis and risk management is one of the effective and productive methods that are used in managing the construction projects for the purpose of increasing the chances of ending the project successfully in terms of cost, time and quality and at the lowest possible problems.
The research aims first to the effective planning for analysis and risk managemen
... Show MoreThe support qualitative information regards as an additional step in the process of decision-making where the method following by companies to provide information help in the creation of value because it is very important to deliver information to investors about their stratigies and what happen truly inside the companies i.e. every case relating with the expectations of stockhotslder and the prices of markets depending on those expectation ,and if the matter isn’t that there will be lack of confidence thate couldn’t be backed again. The decisions of the investors effected by security ,economic ,political, psychological, emotional ,and financial factors .
... Show MoreNitrogen (N) is a key growth and yield-limiting factor in cultivated rice areas. This study has been conducted to evaluate the effects of different conditions of N application on rice yield and yield components (Shiroudi cultivar) in Babol (Mazandaran, Iran) during the 2015- 2016 season. A factorial experiment executed of a Randomized Complete Block Design (RCBD) used in three iterations. In the first factor, treatments were four N amounts (including 50, 90, 130, and 170 kg N ha-1), while in the second factor, the treatments consisted of four different fertilizer splitting methods, including T1:70 % at the basal stage + 30 % at the maximum tillering stage, T2:1/3 at the basal stage + 1/3 at the maximum ti
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