ABSTRACT Background: This study measured the effects of three parameters pH value, length of immersion and type of archwire on metal ions released from orthodontic appliances. Materials and Methods: Ninety maxillary halves simulated fixed orthodontic appliances that were immersed in artificial saliva of different pH values (6.75, 5 and 3.5) during 28 day period. Three types of archwires were used: stainless steel, nickel titanium and thermal activated nickel titanium. The quantity of nickel and chromium ions was determined with the use of atomic force spectrophotometer while iron ions by spectrophotometer. Each orthodontic set was weighted two times, before the ligation and immersion in the artificial saliva and after 28 days at the end of immersion period using analytic balance device. Results: The release different metal ions was observed: nickel (Ni), chromium (Cr) and iron (Fe)). Statistically analysis of variance (ANOVA) and t-test were used. Results showed that (1) the appliances released measurable quantities ofall ions examined; (2) the change in pH had a very strong effect on the release of ions; (3) the release of ions was dependent on wire composition, but it was not proportionalto the content of metal in the wire and (4) orthodontic samples showed decreases in the weight at the end of the study. Conclusion: Levels of released ions are sufficient to cause delayed allergic reactions. This must be taken into account when type of archwire is selected, especially in patients with hypersensitivityor compromised oral hygiene.
The research aims to identify the level of emotional reassurance and level of family climate at
the students of kindergarten Department.
Search tool :
The two researchers built a measure of emotional reassurance and consisting of (26) items and
the scale of family climate consisting of (30 ) items .
The applied Statistical methods:
The two researchers used the statistical bag spss and they used t-test and Pearson correlation
coefficient and analysis of variance and Alpha -Cronbach .
The results showed : The students of kindergarten Department have a high level of
emotional reassurance and good family climate and there is a relationship between emotional
reassurance and family climate .
The two researchers
Background: Postoperative morbidity after extraction of the impacted mandibular third molar (IMTM) is inevitable. One of the most common postoperative complication is alveolar osteitis (AO) which is a painful non healed socket. Many researches were attempted to prevent the occurrence of AO by introducing and applying a new materials inside the extraction socket. Platelet rich fibrin (PRF) is a biological complex fibrin matrix where autologous platelets and leucocytes are present, used to enhance tissue healing process and reduce the early adverse effects of the inflammation. Aims: To evaluate the effect of PRF on the incidence of AO. Also to assess PRF effect on pain, swelling, and trismus following the surgical removal of IMTM and compa
... Show MoreBackground: Postoperative morbidity after extraction of the impacted mandibular third molar (IMTM) is inevitable. One of the most common postoperative complication is alveolar osteitis (AO) which is a painful non healed socket. Many researches were attempted to prevent the occurrence of AO by introducing and applying a new materials inside the extraction socket. Platelet rich fibrin (PRF) is a biological complex fibrin matrix where autologous platelets and leucocytes are present, used to enhance tissue healing process and reduce the early adverse effects of the inflammation. Aims: To evaluate the effect of PRF on the incidence of AO. Also to assess PRF effect on pain, swelling, and trismus following the surgical removal of IMTM and
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In this study, the effect of carboxylic methyl cellulose (CMC), and sodium dodcyl benzene sulfonate (SDBS) as an aqueous solution on the drag reduction was investigated. Different concentrations of (CMC) and (SDBS) such as (50, 100, 150, 200, 250, 300, 350, 400, 450, and 500 ppm) were used to analyze the aqueous solution properties, including surface tension, conductivity, and shear viscosity. The optimum four concentrations (i.e., 50, 100, 200, and 300 ppm) of fluid properties were utilized to find their effect on the drag reduction. Two different PVC pipe diameters (i.e., 1" and 3/4") were used in this work. The results showed that blending CMC with SDBS gives
... Show MoreIntegrated project delivery is collaboratively applying the skills and knowledge of all participants to optimize the project's results, increase owner value, decrease waste, and maximize efficiency during the design, fabrication, and construction processes. This study aims to determine IPD criteria positively impacting value engineering. To do this, the study has considered 9 main criteria according to PMP classification that already covers all project phases and 183 sub-criteria obtained from theoretical study and expert interviews (fieldwork). In this study, the SPSS (V26) program was used to analyze the main criteria and sub-criteria priorities from top to bottom according to their values of the Relative Importance In
... Show MoreThe division partitioning technique has been used to analyze the four electron systems into six-pairs electronic wave functions for ( for the Beryllium atom in its excited state (1s2 2s 3s ) and like ions ( B+1 ,C+2 ) using Hartree-Fock wave functions . The aim of this work is to study atomic scattering form factor f(s) for and nuclear magnetic shielding constant. The results are obtained numerically by using the computer software (Mathcad).
Background: The healing period for bone–implant contact takes 3–6 months or even longer. Application of Escherichia coli-derived recombinant human bone morphogenetic protein-2 (ErhBMP-2) to implant surfaces has been of great interest on osseointegration due to its osteoinductive potential. The objective of this study was to evaluate the effect of ErhBMP-2 on implant stability. Materials and methods: A total of 48 dental implants were inserted in 15 patients. Twenty four implants coated with 0.5 mg/ml ErhBMP-2 (study group). The other 24 implants were uncoated (control group). Each patient was received at least two dental implants at the same session. Both groups were followed with repeated implant stability measurements by me
... Show Moreيشهد العالم تقدما في كافة مجالات الحياة المختلفة وتزداد الحياة صعوبة يوما بعد يوم, ويزداد البحث في كافة المجالات التي تعمل على خدمة الإنسان ولقد طال هذا التقدم النشاط الرياضي ,فقد يكون لتطور التدريب الرياضي وتنوع أساليبه الدور الكبير في تحقيق اللياقة البدنية التي تعد إحدى أهم الأهداف التي يرمي إليها الدرس في كلية التربية الرياضية . واللياقة البدنية تستمد أهميتها من كونها إحدى مكونات اللياقة الشاملة التي بدو
... Show MoreThis study was included preparing acold aqueous extract of clove buds The study also comprised the isolation and studying the proteinous compound,which was seperated using gel filtration technique and determined approximately molecular weight of this isolated compound(6799) dalton . The aim of the study demonstrate effects of the crude aqueous, non proteinous extract, proteinous precipitate and proteinous compound on serum glucose, total cholesterol, triglyceride and high density lipoprotein-cholesterol levels, also glutathione and malondialdehyde levels in liver and kidney tissues in diabetic mice-induced alloxan.Extracts were administerated interaperitioneally. The results were indicated that the crude aqueous, non proteinous extr
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