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Article
Adhesion strength of silicone-based skin adhesive combined with stone-wool fibers

Author: Dr. Arshad F. Jassem Al-Kaabi. * د. ارشد فيصل جاسم
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2015 Volume: 12 Issue: 1 Pages: 71-75
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Aim: The aim of this study is to evaluate and improve the adhesion strength of thesilicone-based skin adhesive for the appropriate functioning time.Method: Two groups of samples were prepared, six samples per group, and a humansurrogate skin samples were used made from cross-linked polyamide polymerresembling the stratum corneum layer of the human skin. A 180 degree peel testwas performed to measure the adhesion strength.Results and conclusion: The results showed that there was a statistically significantdifferent in the amount of adhesion strength between the two groups whichconfirmed that the stone-wool fiber addition had increased the adhesion strengthof the silicone-based skin adhesive.


Article
The Effect of Chemomechanical Caries Removal and Different Bonding Systems on Shear Bond Strength of Carious Dentin (In Vitro Study)

Authors: Dr. Shatha Abdullah Salih B.D.S, M.Sc د.ثذى عبد الله صلاح --- Dr. Twana Ihssan Mohammed B.D.S د.توانا احسان
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2011 Volume: 8 Issue: 2 Pages: 115-126
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The purpose of this in vitro study was to determine whether shear bond strength(SBS) to chemomechanically excavated dentine by Carisolv (CS) differed from theSBS after conventional caries removal by bur (CB), with the use of the followingadhesive systems: [Total-etch (TE), etch and Compobond1, etch, prime and bondingresin]; [Self-etch (SE), Xeno v, one component self-etching dental adhesive] and [Noetch(NE), Compobond1, prime& bond only]. Fifty human molars with occlusal carieswere used to prepare dentin samples which were assigned to 5 groups: group I and IIIthe prepared samples treated by CB and CS respectively then with TE, group II andIV the prepared samples treated by CB and CS respectively then with SE, while ingroup V the prepared samples treated by CS and then with NE. For each sample therewas light cured composite core build up. After water storage, the samples were testedin a single-plane shear test assembly. The results demonstrated that there werestatistical significant differences with in the mode of caries removal groups and alsothere were statistical significant differences between the bonding systems which affectSBS of carious dentin at p < 0.01, with in favor of the TE over SE. The present datademonstrate that with the use of CS on (carious dentin, there was either increase ordecrease in bond strength in relation with different bonding systems.


Article
Comparative Evaluation of the Effect of Different Universal Adhesives and Bonding Techniques on the Marginal Gap of Class I Composite Restoration (A SEM Study)

Authors: Ali F. Al-Qrimli علي القرملي --- Abdulla M.W. Al-Shamma عبد الله محمد وجيه الشماع
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2016 Volume: 28 Issue: 4 Pages: 34-42
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: With the increase in composite material use in posterior teeth, the concerns about the polymerization shrinkage has increased with the concerns about the formation of marginal gaps in the oral cavity environment. New generation of adhesives called universal adhesive have been introduced to the market in order to reduce the technique sensitive bonding procedures to give the advantage of using the bonding system in any etching protocol without compromising the bonding strength. The aim of the study was to study marginal adaptation of two universal adhesives (Single bond™ Universal and Prime and Bond elect) using 3 etching techniques under thermal cycling aging.Materials and Methods: Forty-eight sound maxillary first premolar teeth were included in the study. Teeth were divided into two groups according to the universal adhesive used then each group was subdivided into 3 subgroups according to the etching protocol used. Standardized class I cavities were prepared in the teeth followed by the restoration of teeth using Filtek™ Bulk Fill Posterior Restorative composite material. After finishing and polishing, teeth were subjected to 500 thermal cycles in 55º-5ºC bath with dwell time of 30 seconds. Teeth then were examined using SEM to measure the marginal gap at 12 points. Data obtained were analyzed using one-way ANOVA and LSD test for each group and with student t-test to compare the two adhesives.Results: The result of this study the showed that etch and rinse technique showed significantly the least marginal gap width for both adhesive types. The selective etch technique showed lower gaps compared to the self-etch technique with no significant difference. The result showed that single bond universal showed significantly the least marginal gap for the all etching techniques compared to Prime and bond elect.Conclusion: The etch and rinse technique remains the most suitable technique for adhesive restoration. The type of adhesive plays an important role in adhesion


Article
Bond and rebond strengths an in vitro and in vivo evaluation

Author: Hussain A OBAIBI
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2001 Volume: 1 Issue: 1 Pages: 24-29
Publisher: Mosul University جامعة الموصل

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Abstract

New orthodontic adhesives should be put under vitro and vivo investigation to evaluate their efficiencies and disadvantages, so that, Concise, No Mix and Right On orthodontic adhesives were tested in vitro and evaluated clinically by treating (15) cases. These adhesives were used in bonding (10) human sound extracted premolars for each one according to the manufactures instructions, and then rebonded new brackets to these tested teeth after cleaning and polishing.The adhesive were used in bonding the brackets to the 40 teeth clinically (five upper dental arches) for each type, according to their manufacturer ' s instructions. The lowest number of failure brackets was within the use of concise adhesive.The shear bond and rebond strength were measured in compression test Machine in Mega Pascal (Mpa).The results showed that the Concise adhesive had strongest bond and rebond strength in vitro and clinically than that No Mix and Right-On adhesives and the later adhesives had adequate bonds strength and more successful in bonding anterior brackets


Article
Evaluation of the shear bond strength of four orthodontic adhesive systems

Author: Mahmood Kh Ahmed
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2007 Volume: 7 Issue: 1 Pages: 66-70
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: To evaluate shear bond strength of four types of orthodontic adhesive systems including two–paste composite (Concise), light–cured composite (Transbond), no–mix composite (Alpha–dent) and light–cured glass ionomer cement (Fuji), and to compare shear bond strength between these four types of orthodontic adhesive systems. Materials and Methods: Forty extracted premolars and forty stainless steel mesh edge–wise brackets were used. Each type of orthodontic adhesives were used for bonding of ten brackets according to its manufacturer instructions, after setting the brackets were debonded and the shear bond strength were measured using Instron testing machine. Results: Showed that the two–paste composite (Concise) and the light–cured composite (Transbond) gives the highest bond strength, the bond strength of the glass ionomer cement (Fuji) significantly lower than that of Concise and Transbond but it was remained within the accepted level for clinical use, the no–mix composite (Alpha–dent) showed very low shear bond strength which was below the accepted value for clinical application. Conclusions: Concise and Transbond have high bond strength so that it can be used to fix orthodontic attachment in areas subjected to high force. The bond strength of the glass ionomer cement (Fuji) remains within the accepted level for clinical use with the benefit of fluoride release. Also the shear bond strength of the no–mix composite (Alpha–dent) is very low makes it not suitable for clinical use.


Article
Preparation and Diagnosis of Polyethylene Terephalate (PET) and Studying of its Effect as Additives on the Concrete Properties
تحضير و تشخيص البولي اثلين ترفثاليت و دراسة تأثيره كمضاف على خصائص الكونكريت

Author: Thamir Salman Bachari ثامر سلمان البجاري
Journal: Basrah Journal for Engineering Science مجلة البصرة للعلوم الهندسية ISSN: Print: 18146120; Online: 23118385 Year: 2013 Volume: 13 Issue: 1 Pages: 80-100
Publisher: Basrah University جامعة البصرة

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Abstract

Polyethylene terephthalate (PET) was prepared from (PET) flakes and 25% of NaOH solution were added to in tri-neck flask, the reaction run for six hours at temperature (100-130) oC and the precipitate was reacted with ethylene glycol at temperature (130-160) oC. IR spectrophotometer was used for the diagnoses of (PET). Differential scanning calorimeter (DSC) is used to indicate glass transition temperature Tg, the melting temperature Tm and the heat absorbed. Part hundred ratios (phr,s) of (PET) rather than dosage of PET in gms. To concrete cubes were added to study its effect on concrete properties. Additives of (phr,s) impart performance such as increased cement dispersion, and enhance the performance of concrete which was appeared in maintaining a lengthening or slow the setting time that meets product and job needs. Maximum and minimum compressive strength is 43.7 MPa and 30.0 MPa at 0.3 gm. and 0.1 gm. respectively.

: تم تحضير البولي إثلين ترفثاليت من رقائق قناني الماء البلاستيكية المستخدمة للشرب وإضافة 25% من محلول هيدروكسيد الصوديوم بالماء المقطر في دورق ذو ثلاثة أعناق وتم التفاعل بعد مرور ست ساعات في درجة حرارة (100-130) oم وتم معاملة الراشح مع الاثلين كلايكول في درجة حرارة (130-160) oم .تم استخدام جهاز قياس طيف الأشعة تحت الحمراء لتشخيص البولي اثلين ترفثاليت. إن درجة حرارة الانتقال الزجاجي, درجة حرارة الانصهار وكمية الحرارة الممتصة من قبل النموذج تم دراستها باستخدام جهاز المسعر الحراري التفاضلي. تم إضافة نسب جزء مئات من البولي اثلين ترفثاليت و فضلا عن مضافات وزنيه لعمل المكعبات الكونكريتية. لدراسة تأثيرها على خصائص الكونكريت. إن عمل هذه الإضافات هو تحسين أداء خصائص الاسمنت كزيادة التشتت, العمل على تحسين اداء الكونكريت والتي تظهر من حيث إطالة أو إبطاء زمن التصلب التي تواجه المنتج واحتياجات العمل. ان أعلى وأوطأ مقاوميه انضغاطية 43.4 ميكاباسكال و 30.0 ميكاباسكال عند 0.7 غم و 0.1 غم على التوالي.


Article
Adhesive strength improvement of epoxy resin with different reinforcing materials
تحسين قوة اللصق لراتنج الايبوكسي بواسطة مواد معززة مختلفة

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Abstract

AbstractAbstract: This research was carried out by adding several reinforcement materials to the epoxy type (Henkel/pattex) then the shear strength was measured. It was noticed from experimental results that there is a significant improvement achieved by adding the reinforcement materials. Also the change of the percentage of the reinforcement materials was studied and its effect on the shear strength was considered. The reinforcement materials include iron filing, silicon carbide as weight percentages 10%, 20% and 30%. Also steel mesh, polymers mesh and fiber glass was used. The cling was carried out on standard specimens including galvanized steel, aluminum and brass. The results obtained shows that the shear strength was significantly improved by adding the reinforcement materials .The results were affected by the type of reinforcement materials and type of metals being glued. The maximum improvement obtained with brass/brass specimen using mixture of epoxy with 10% iron filing as a weight percentage.Key words: Adhesives, Epoxy, Reinforcement materials, Shear strength.

الخلاصة:تضمن البحث إجراء دراسة عملية حول تأثير إضافة مواد تقوية على إجهاد القص لمادة الايبوكسي نوعHenkel/pattex) ) واشتمل البحث تغيير نسب الإضافة لمواد التقوية وتأثير هذا التغيير على إجهاد القص لطبقة اللصق .اختيرت مواد تقوية شملت برادة الحديد و كاربيد السليكون بنسب وزنيه ( 10% ، 20% و 30% ). كذلك تم استخدام شبكة معدنية ، شبكة بوليمرية وألياف زجاجية حيث تم لصق نماذج قياسية معدنية من الصلب المغلون ،الألمنيوم والبراص . تم قياس إجهاد القص للنماذج التي تم لصقها باللواصق المصنعة ولوحظ من النتائج العملية حصول تحسن كبير في إجهاد القص وتباينت نسبة التحسن باختلاف مواد التقوية المضافة ونوع المعدن المستخدم وتم الحصول على اكبر نسبة تحسن في إجهاد القص لنماذج البراص/براص الملصوقة باستخدام ايبوكسي مضافا له برادة حديد بنسبة 10% كنسبة وزنيه


Article
Comparative Evaluation of Shear Bond Strength of Flowable Composite Bonded to Teeth Enamel with Laser Surface Treatment.

Authors: Abdulrahman K. Muhammed --- Makdad Chakmakchi
Journal: Journal of Oral and Dental Research مجلة طب الفم والاسنان ISSN: 23106417 Year: 2015 Volume: 2 Issue: 1 Pages: 24-31
Publisher: Iraqi Association for Oral Research الجمعية العراقية لبحوث طب الفم

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Abstract

Background: Acid etching of enamel appears to improve retention by selectively eroding certain hydroxyapatiteformations and facilitating penetration by the development of resin tags. Aim of study: To evaluate shear bond strength(SBS) of flowable composite to non-lased and lased groups, compare the (SBS) of flowable composite between Totaland Self-etch in non-lased and lased groups, and failure mode analysis.Materials and Methods: Forty bovine incisorswere used, enamel surfaces was grounded by silicon carbide paper and samples were randomly assigned into twomain groups (Group A: Non lased n=20, Group B: lased prepared n=20). Each main group was subdivided randomlyaccording to the adhesive systems that used which are: total-etch adhesive and self-etch adhesive, which were appliedto the prepared enamel surface according to manufacture instruction. Composite rod applied over the bonded area andcured. Samples were stored in distilled water at 370 for 24 hours. The evaluation of shear bond strength was employedby the use of universal testing machine. Results: The results of Student’s t-test showed that there was no significantdifference between the lased and non-lased enamel groups (P= 0.311). One–way ANOVA test and Duncan's MultipleRange test that compare shear bond strength between total and self-etch adhesives showed no significant differencein both lased and non-lased enamel groups. Conclusion: The mean shear bond strength and enamel surface etchingobtained with an Er,Cr:YSGG laser was not comparable to that obtained with non- lased enamel surface.


Article
Study the Effect of Preparation and Diagnosis of Polyethylene Terephthalate (PET) As Additive Modification on Concrete Properties

Author: Thamir Salman Bachari
Journal: Basrah Journal for Engineering Science مجلة البصرة للعلوم الهندسية ISSN: Print: 18146120; Online: 23118385 Year: 2015 Volume: 15 Issue: 1 Pages: 25-31
Publisher: Basrah University جامعة البصرة

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Abstract

The polyethylene terephthalate (PET) was prepared from PET flakes of empty local water drinking bottles and diagnosis by infrared spectroscopy (IR). The glass transition temperature, melting temperature Tm and heat capacity were indicated by differential scanning calorimeter (DSC). Part hundred ratios (phr,s) of (PET) were added to study its effect on concrete properties. Additives of (phr) impart performance such as increased cement dispersion, enabling drastically reduced water requirements. Enhance the mortar cubes performance; depend on the compatibility of cement with PET. Porosity of mortar cubes with cement, sand and added PET products were calculated. Maximum and minimum Compressive strength were calculated 58.76 MPa, and 24.0 MPa at phr 0.04 and 0.07 of PET with cement. And PET with cement and sand were calculated 16.5 MPa and 4 MPa at dosages 0.03 gm. and 0.08 gm. The relative dosages in calculating porosity percentages are (0.06, 0.1 and 0.3) gm.


Article
Enamel surface damage after Use of self-etched Flowable composite and conventional orthodontic bonding systems "An in vitro study"
ضرر سطح المينا بعد استعمال الرابط المائع ذاتي اللصق وأنظمة الربط لتقويم الأسنان التقليدية "دراسة في المختبر

Author: Rawof R. Al-Tuma رؤوف رشيد جواد ال طعمة
Journal: karbala journal of pharmaceutical sciences مجلة كربلاء للعلوم الصيدلانية ISSN: 70272221 Year: 2016 Issue: 11 Pages: 116-123
Publisher: Kerbala University جامعة كربلاء

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Abstract

Background: This study aims to evaluate enamel surface damage and the site of bond failure afterusing of two materials with each has different adhesive techniques. One of them is self-etch (7thgeneration bonding system) while the other with three steps conventional technique(5th generationbonding system).Materials and methods: eighty premolars, extracted for orthodontic purposes, were divided into 4groups of 20. The enamel surfaces were examined with 10X magnifying lens. Two types ofbracket (stainless steel and ceramic) was bonded and debonded in each group using ligature wirecutter. The three steps adhesives was conventional orthodontic bracket adhesive of Oromcocompany, the self-etch flowable adhesive was Vertise flow flowable composite of Kerr company;After debonding, the enamel surfaces were inspected under a stereomicroscope to determine thepredominant site of bond failure and adhesive remnant index. Then stereomicroscope was used toevaluate enamel surface damage after the removal of residual adhesive.Results: The reduction in enamel surface damage showed a statistically non-significant with theuse of self-etched flowable adhesive in both ceramic and stainless steel brackets groups. Theamount of the adhesive remained on the tooth surface significantly increase for groups thatbonded with self-etched flowable adhesive in both stainless steel and ceramic brackets. Thepredominant failure site in self-etch flowable adhesive was between enamel and bracket for bothtypes of brackets.Conclusion: The enamel surface damage that results from debonding of conventional orthodonticadhesives was non significantly higher than that found with self-etch flowable adhesive for bothmetal and ceramic brackets "used in this study"

تهدف هذه الدراسة إلى تقييم أضرار المينا السطحية وموقع من فشل السندات بعد استخدام اثنين من المواد مع بعضها لديهاتقنيات لاصقة مختلفة .واحد منهم هو اللصق الذاتي نظام الربط جيل في حين أن الآخر مع ثلاث خطوات (تقنية التقليدية )10 عدسة X ثمانون سن ضاحك مقلوعة لأغراض تقويم الأسنان، تم تقسيمهم إلى 4مجموعات . تم فحص السطوح المينا معمكبرة . مع استخدام نوعين من سنادات التقويم (الفولاذ المقاوم للصدأ والسيراميك) . اللواصق المستخدمة كانت اللاصق التقليديبعد رفع الروابط، تم تفتيش السطوح المينا باستخدام المجهر ؛Kerr والاصق الذاتي المائع لشركة ،Ormco لتقويم من شركةلتحديد موقع فشل السندات والبقايا اللاصقة ثم تقييم ضرر المينا بعد إزالة اللواصق المتبقية

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