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Article
An Evaluation of the Effect of Bleaching Agent on Microhardness of a New Silorane-Based Restorative System and Methacrylate-Based Restorative Material

Authors: Shatha Abdul Kareem --- Rasha Hameid Jehad
Journal: Journal of University of Babylon مجلة جامعة بابل ISSN: 19920652 23128135 Year: 2012 Volume: 20 Issue: 1 Pages: 385-363
Publisher: Babylon University جامعة بابل

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Abstract

Background: The high reactivity of hydrogen peroxide used in bleaching agents have raised important questions on their potential adverse effects on physical properties of restorative materials. The purpose of this in vitro study was to evaluate the effect of in-office bleaching agents on the microhardness of a new Silorane-based restorative material in comparison to methacrylate-based restorative material.Materials and method: Forty specimens of Filtek™ P90 (3M ESPE,USA) and Filtek™ Supreme XT (3M ESPE, USA) of (8mm diameter and 3m height) were prepared. All specimens were polished with Sof-Lex disks (3M ESPE, USA). All samples were rinsed and stored in incubator 37˚C for 24 hours in DDW. Ten sample of each material were subjected to 37.5% hydrogen peroxide gel (Pola office +, SDI)for 8 minutes while exposed to light curing device, this step was repeated three times for 3 weeks. While the other ten samples for each material was served as control. All specimens were subjected to microhardness test using digital microhardness tester to determine the VHN (Vickers Hardness Number)Results : The Filtek™ P90 exhibited higher microhardness value than Filtek™ Supreme XT. After hydrogen peroxide treatment, both types of composites exhibited low microhardness values but still Filtek™ P90 is harder than Filtek™ Supreme XT.Conclusion : In-office hydrogen peroxide bleaching agent resulted in reduction in microhardness values for both composite materials. Silorane- based composite is more affected by the bleaching agent than methacrylate-based composite.


Article
Effect of 38%hydrogen peroxide agent on color change of composite resins stained with tea and coffee beverages (An in vitro study)

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Abstract

Background: The esthetic application of bleaching materials has gained popularity,with consequences for teeth and restorative materials. The purpose of this an invitro study was to investigate the effect of in-office bleaching agent (38%hydrogen peroxide) on the color change of three composite resins after stainingwith tea and coffee beverages.Materials and Methods: Sixty disc-shaped samples from three different compositeresins (Tetric Ceram, Tetric Flow and Tetric Evo Ceram) were used in this study.The samples of each group were randomly divided into two subgroups accordingto type of beverages (tea and coffee) used for staining of samples. After stainingof composite resins the total color change (ΔE1 ) was calculated usingspectrophotometer, then the samples immersed in WHITEsmile® office bleachingagent for 15 min x 3 times with a 7 days interval followed by ΔE2 calculation.Data were subjected to the ANOVA, LSD and student t-test at 0.05 significancelevel.Results: The results revealed that, there was clinically significant color change ΔE>3.3 with a statistically highly significant differences (P=0.000) for all the groups.Coffee causes more discoloration than tea. After bleaching, the samples becamewhiter in color and only appreciable by skillful operator but considered clinicallyacceptable ΔE1 - ΔE2 < 3.3.Conclusion: Tea and coffee beverages causes discoloration in composite but thiseffect was depended on the type of beverages and composite resins. The most ofcolor change occurred with Tetric Flow composite resin after immersion in coffeebeverage. The bleaching agent (38% hydrogen peroxide) can remove the stainingof composite resins and make its color clinically acceptable.


Article
A comparative study evaluates the effect of Hydrogen peroxide 38% and Carbamide peroxide 35% bleaching products on enamel microhardness (In vitro study)

Author: Dr. Reem Hassan Majeed, BDS. MSc د. ريم حسان مجيد
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2012 Volume: 9 Issue: 2 Pages: 164-171
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The aim of this study was to compare the effect of two professional bleachingproducts (in-office Opalescence Boost hydrogen peroxide 38%) and (home bleachingOpalescence carbamide peroxide 35%) on enamel microhardness.The sample consist of thirty maxillary first premolars teeth (freshly extracted),caries free obtained from children aged 12 years old under routine orthodontictreatment. The teeth were sectioned mesiodistally parallel to the long axis of tooth andmounted on acrylic mold. The specimens were divided into two halves buccal andpalatal as per treatment, the buccal half served as experimental, while the palatal halfserved as control (1) and kept in artificial saliva at 37c0 for two weeks. Microhardnesstest were obtained before and after bleaching.Results indicated that teeth specimens submitted to Opalescence carbamideperoxide 35% showed highly significant reduction in enamel microhardness P<0.01,while no-significant difference in enamel microhardness in specimens submitted toOpalescence Boost 38% hydrogen peroxide P>0.05.In this study Opalescence carbamide peroxide 35% leads to the significantdecrease in enamel microhardness compared to Opalescence Boost hydrogenperoxide 38%.


Article
Influence of crude extract of Hawthorn crataegus oxyacantha on some physiological aspects in mature male Rats exposed to hydrogen peroxide over load.
تأثيرالمستخلص الخام لثمار الزعرور على بعض الصفات الفسلجية الناتجة من فرط بيروكسيد الهيدروجين في ذكور الجرذان البالغة

Author: Anwar I. Obeed Al-Abdaly انوار ابراهيم عبيد العبدلي
Journal: The Iraqi Journal of Veterinary Medicine المجلة الطبية البيطرية العراقية ISSN: 16095693 Year: 2012 Volume: 36 Issue: 1 Pages: 37-44
Publisher: Baghdad University جامعة بغداد

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Abstract

This study was carried out to investigate the protective effects of 70% ethanolic alcohol extract of hawthorn (crataegus oxycantha) on some physiological functions of male rats exposed to 1% H2O2. Fifteen mature male Newzeland rats were randomly divided into three groups:- control group (C) ,two groups treated with 1% H2O2 alone (G1) or 1%H2O2 with crude extract of hawthorn(G2) orally daily for 30 days .Blood samples were taken at zero time and 30 days of the experiment .The present study declared an alteration in the lipid profile of the treated group (G2) at the end of treatment (30 days) manifested by asignificant reduction (p<0.05) in serumTC,TAG,LDL-C, VLDL-C concentrations. And elevation (p<0.05) in serum, HDL-C, as compared to the treated group (G1). Antioxidant status also exhibited significant (p<0.05) changes characterized by an elevation of serum GSH in group (G2). Histological study revealed that oral treatment with 1% H2O2 caused congestion of blood vessels of the heart with infiltration of inflammatory cells and odema between muscle fibers. It is concluded that treatment with hawthorn showed no clear pathological lesions.

أجريت هذه الدراسة لمقارنة الدور الوقائي للمستخلص الكحولي(70% من الكحول الأثيلي) لثمار الزعرور في بعض المؤشرات الفسلجية في ذكور الجرذان المعرضة للأجهاد التاكسدي بواسطة 1% من بيروكسيد الهيدروجين . تم أستخدام خمسة عشر جرذا نيوزيلانديا من الذكور البالغة قسمت عشوائيا الى ثلاثة مجاميع متساوية:- مجموعة سيطرة(C) أعطيت ماء الشرب الأعتيادي, ومجموعتين معالجة أعطيت ماء الشرب الأعتيادي مضافا اليه بيروكسيد الهيدروجين بتركيز 1% لوحده (G1) أو مضافا أليه المستخلص الكحولي لثمار الزعرور(G2) لمدة ثلاثين يوما . تم سحب عينات الدم للفترات 0 و 30 يوم من التجربة. أظهرت الدراسة الحالية تغيرا ملحوظا في دهون الدم للمجموعة المعاملة الثالثة بعد 30 يوما من المعالجة والتي تميزت بأنخفاض معنوي اكبر من 0.05 في الكوليسترول الكلي والدهون الثلاثية وكوليسترول الشحوم البروتينية واطئة الكثافة وكوليسترول الشحوم البروتينية ذات الكثافة الواطئة جدا , بالأضافة الى الأرتفاع المعنوي في تركيز الكلوتاثيون في مصل الدم . بينت نتائج الفحص النسيجي حدوث احتقان الأوعية الدموية في قلب الجرذان المعاملة ب 1% من بيروكسيد الهيدروجين مع وجود ارتشاحات التهابية خلوية ووذمة بين الألياف العضلية . لم تظهرالمعاملة بالمستخلص الكحولي للزعرور اي أفات مرضية .


Article
Effect of Grape Seeds Powder on the Level of Some Antioxidants and Lipid Peroxidation of White Male Albino Rats Exposed to Oxidative Stress
تأثير مسحوق بذور العنب في بعض مستويات مضادات الأكسدة وبيروكسدة الدهن لذكور الجرذان البيض المعرضة للإجهاد التأكسدي

Authors: Eman S. Mahmmud إيمان سالم محمود --- Rukzan M. Daoud ركزان محمود داؤد --- Muna H. Jankeer منى حسين جانكير
Journal: Rafidain journal of science مجلة علوم الرافدين ISSN: 16089391 Year: 2012 Volume: 23 Issue: 1A Pages: 67-78
Publisher: Mosul University جامعة الموصل

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Abstract

The present study included the investigation of the effect of grape seeds powder Vitis vinifera in preventing oxidative stress induced by hydrogen peroxide H2O2 at a concentration 0.5 % given with consumed drinking water in male albino rats Rattus norvegicus aged 2.5 – 3 months. Rats were randomly divided into 5 groups (5 rats/group) and the rats were treated with forage to which grape seeds powder were added at different concentrations 200, 400, 600 mg/kg. B. Wt. of grape seeds powder daily for eight weeks.The results showed that treatment with 0.5% H2O2 caused a significant increase in malondialdhyde (MDA), bilirubin and uric acid level and a significant decrease in glutathione (GSH), albumin level and the enzyme activity of superoxide dismutase (SOD) in the serum of treated rats compared with control group, also the above changes indicating the ability of H2O2 to induce the oxidative stress in albino rats.The results also showed that treatment with grape seeds powder caused a significant decrease in MDA, bilirubin and uric acid level and a significant increase in GSH, albumin level and the activity of SOD compared with control. The results also showed the decrease and increase were more prominent in rats treated with 600 mg /kg. B. Wt. of grape seeds powder, these results indicate the protective effect of grape seeds powder against oxidative stress.

تضمنت الدراسة الحالية معرفة تأثير مسحوق بذور العنب Vitis vinifera في قدرته على الحماية من الإجهاد التأكسدي المحدث ببيروكسيد الهيدروجين H2O2 بتركيز 0.5 % المستهلك في ماء الشرب من قبل ذكور الجرذان البيض Rattus norvegicus بعمر 3 – 2.5 أشهر، ثم قسمت الجرذان عشوائياً إلى خمس مجموعات بواقع (5 جرذ/ مجموعة) وغذيت بعليقة مضافاً إليها مسحوق بذور العنب بتراكيز مختلفة 200، 400، 600 ملغم / كغم من وزن الجسم يومياً ولمدة 8 أسابيع.أظهرت نتائج المعاملة ببيروكسيد الهيدروجين %0.5 ارتفاعاً معنوياً في مستوى المالوندايالديهايد والبيليروبين وحامض اليوريك وانخفاضاً معنوياً في مستوى الكلوتاثيون والالبومين وفعالية أنزيم سوبر أوكسايد دسميوتيز مقارنة مع مجموعة السيطرة، مما يدل على قابلية بيروكسيد الهيدروجين في إحداث الإجهاد التأكسدي في الجرذان البيض. كما أظهرت نتائج المعاملة بمسحوق بذور العنب انخفاضاً معنوياً في مستوى المالوندايالديهايد والبيليروبين وحامض اليوريك وارتفاعاً معنوياً في مستوى الكلوتاثيون والالبومين وفعالية أنزيم سوبر أوكسايد دسميوتيز مقارنة مع مجموعة السيطرة. كما أوضحت النتائج أن الانخفاض والارتفاع كان أكثر وضوحاً في مجموعة الجرذان المعاملة بتركيز 600 ملغم / كغم وزن الجسم من مسحوق بذور العنب، وهذا يدل على أن لمسحوق بذور العنب تأثيراً مضاداً للأكسدة.

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