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Article
X-ray diffraction and biocompatibility of glass ionomer cement reinforced by different ratios of synthetic hydroxyapatite

Authors: Mohammed R. Al.Jabouri --- Zainab M. Abdul-Ameer
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 3 Pages: 62-68
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This study was done to assist X-ray diffraction and biocompatability of glass ionomer cement reinforcedby different ratios of Hydroxyapatite.Materials and Methods: The powder of glass ionomer cement reinforced by different ratios of Hydroxyapatite wereused to get X-ray diffraction pattern by X-ray diffraction machine, While for biocompatibility test, A polyethylenetubes containing glass ionomer cement reinforced by different ratios of Hydroxyapatite were implanted on thedorsal submucosal site of Rabbit's tissues and histological slide were prepared for histopathological study.Results: X-ray diffraction test showed that all elements of glass ionomer cement reinforced by different ratios ofHydroxyapatite were react with each other and all the final products none crystalline in nature with small amount ofHydroxyapatite present unreacted may be act as cores for final reacted elements. The histological test showed mildirritation to Rabbit's tissues by glass ionomer cement reinforced by different ratios of Hydroxyapatite, this irritationsubsided with time.Conclusions: there is chemical reaction of all elements of glass ionomer cement reinforced by different ratios ofHydroxyapatite and new final products were results .Also glass ionomer cements reinforced by different ratios ofHydroxyapatite were biocompatible with Rabbit’s tissues


Article
Microleakage of Root Canal Sealed with Temporary Endodontic Sealing Materials

Author: Rajaa T .Sulieman
Journal: Tikrit Journal for Dental Sciences مجلة تكريت لعلوم طب الاسنان ISSN: 20731213 Year: 2014 Volume: 3 Issue: 1 Pages: 24-29
Publisher: Tikrit University جامعة تكريت

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Abstract

To measure the microleakage of different materials used as temporary endodontic sealing materials and to compare between them. Sixty sound human premolars extracted for orthodontic purpose, caries and cracks free were used. Teeth were divided into 6 groups depending on type of temporary materials (glass ionomer cement, zinc phosphate cement, amalgam, temporary filling "zinc oxide eugenol") for temporization and control groups (negative and positive). For each tooth, an access opening was done followed by instrumentation, irrigation and dryness. Then application of different temporary materials. Evaluation of marginal microleakage (tooth – restoration interface) were done by using dye penetration test. The study was done in Department of Conservative Dentistry, College of Dentistry, University of Mosul. The results showed significant differences (p< 0.05) in marginal microleakage among groups tested. But there were no significant difference between buccal and lingual tooth restoration – interface for each group. Glass ionomer cement showed less microleakage at tooth – restoration interface when compared with other temporary filling materials which used in this study. Glass ionomer cement has superioer effect on reduction of microleakage when compared with other temporary filling,when used for temporization had more ability to reduce microleakage than zinc phosphate cement, amalgam and lastly temporary filling (zinc oxide eugenol).


Article
Effectiveness of mixing procedure on the microleakge of glass ionomer cement as filling material in primary molars (in vitro study)

Author: Maha Abdul- Kareem مها عبد الكريم
Journal: Tikrit Journal for Dental Sciences مجلة تكريت لعلوم طب الاسنان ISSN: 20731213 Year: 2015 Volume: 3 Issue: 1 Pages: 55-61
Publisher: Tikrit University جامعة تكريت

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Abstract

Background: Well-adapted restorations with adequate marginal sealing are of extreme importance for the success of atraumatic restorative treatment, The present study was carried out to find if the mixing procedure affect the marginal seal of hand mixed and capsulated glass-ionomer in Class I cavities of 30 non carious primary molars.Materials and Methods:Standardized Class I cavity preparations were prepared in 30 extracted sound primary molars. The teeth were then randomly divided into two groups: Group I: filled with mechanically mixed (capsulated) glass ionomer cement (GIC). Group II: filled with hand mixed glass ionomer . After that the teeth were subjected to 250 thermal cycles with a 15 second dwell time in each, then sectioned to be examined under the stereo microscope.Results:The sealing ability of the GIC filling materials was determined by their ability to inhibit dye penetration. Data were analyzed according to t-test. The hand mixed GIC provides a better seal than capsulated GIC, there were no significant differences between the two studied groups in their resistance to dye penetration. Conclusion: Hand mixed GIC presented a better performance regarding microleakage in comparison to capsulated GIC.


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: 9 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
ROOT REINFORCEMENT USING CAST POST CEMENTED WITH DIFFERENT TYPES OF CEMENTS

Authors: Mohammed F. Moutlak B.D.S.,M.Sc * * د. محمد مطلق --- Fareed Ghiab Nu'man B.D.S.,M.Sc * د. فريد غايب النعيمي
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2006 Volume: 3 Issue: 2 Pages: 122-126
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The purpose of this in-vitro study is to evaluate and compare the fractureresistance of endodontically treated teeth restored using cast posts cemented withdifferent types of cement. Thirty intact human maxillary central incisors were selectedfor this study. The crowns were removed and endodontic therapy were done on theroots, which were then prepared to receive cast posts, after their fabrication, the castposts were cemented with zinc phosphate cement (group I), resin modified glassionomer cement (group II),and resin cement (group III). The samples were subjectedto compressive fracturing loads by a Zwick testing machine at a cross head speed of5mm/min., with an angle of 45º to the long axis of the tooth. The results showed thatthe posts cemented with resin cement exhibited the highest mean failure load followedby posts cemented with resin modified glass ionomer cement , while posts cementedwith zinc phosphate cement exhibited the lowest mean failure load.


Article
Evaluation of Marginal Adaptation of Metal Ceramic Crown with Different Luting Cement

Author: Nadia M. Al-Shakir نادية مظفر الشاكر
Journal: Tikrit Journal for Dental Sciences مجلة تكريت لعلوم طب الاسنان ISSN: 20731213 Year: 2013 Volume: 2 Issue: 2 Pages: 117-122
Publisher: Tikrit University جامعة تكريت

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Abstract

The study aims to evaluate and compare the microleakage of three different luting materials. The materials compared are Zinc phosphate cement, Variolink II Refill and Glass ionomer resin cement. Eighteen recently extracted caries-free wisdom teeth were used . The teeth were cleaned then stored in distilled water until use. The molars were assigned randomly into three groups of 6 teeth of each . The metal ceramic crowns were constructed by means of an indirect laboratory technique. In group A, the crowns were cemented with a traditional Zinc Phosphate. In group B, the tooth preparations were sealed with Variolink II Refill. In group C, the tooth preparations were sealed with glass ionomer resin cement prior to cementation with the crowns. The results showed higher value of microleakage for Zinc phosphate cement. While the least value was for the Variolink II . The value for Glass ionomer resin cement was low. Statistically analysis revealed difference between the Zinc phosphate cement ,Variolink II and Glass ionomer resin cement in microleakage. There was no significant difference in microleakage between Variolink II and Glass ionomer resin cement. This may indicated that the degree of microleakage may influenced by the type of the luting system used.


Article
Comparison of regional bond strength among different types of posts luted with different types of cement

Authors: Ahmed A. Al-Jumaily احمد الجميلي --- Haitham J. Al-Azzawi, هيثم العزاوي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 1 Pages: 1-6
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This in vitro study was carried out to investigate the effect of post space regions (coronal, middle and apical), the effect of post types ( Manually Milled Zirconia post, Prefabricated Fiber post, prefabricated Zirconia post) and the type of cement used (GIC, self-adhesive resin cement) on the bond strength between the posts and root dentin by using push-out test.Material and methods: Forty eight mandibular premolars extracted for orthodontic reasons (single rooted) were instrumented with ProTaper system (hand use) and obturated with gutta percha for ProTaper using AH26® root canal sealer following the manufacturer instructions. After 24 hours, post space was prepared using Zirix and Glassix drills no.3 creating 8 mm depth post space. The prepared samples were randomly divided into three main groups (16 samples each) according to the type of post used (Group A. Manually Milled Zirconia post, Group B. Prefabricated Fiber post and Group C. Prefabricated Zirconia post) .each group was subdivided into two subgroups (each subgroup contains 8 samples) according to the type of cement used (subgroup A1.Manually Milled Zirconia post cemented with GIC, subgroup A2.Manually Milled Zirconia post cemented with Speed cem),( subgroup B1.Prefabricated Fiber post cemented with GIC, Group B2. Prefabricated Fiber post cemented with Speed cem) and (subgroup C1.Prefabricated Zirconia post cemented with GIC, subgroup C2. Prefabricated Zirconia post cemented with Speed cem), after cementation and incubation for 24hrs, at 37°c and 100% humidity. Each root was sectioned horizontally into 3 slices (2 mm in thickness) representing the coronal, middle and apical regions of the post space. Push out bond strength test was performed and measured using a universal testing machine (Tinius-Olsen) at across head speed of 0.5 mm/min.Results: The results showed that regarding the root region, the bond strength values increased significantly from apical to coronal region for all types of posts in both tested cements. For the effect of post type, the manually Milled Zirconia post cemented with the self-cured resin cement (Speed cem) showed higher bond strength values. For type of cement, the self-adhesive resin cement (Speed cem) showed higher bond strength values.Conclusions: the retention of post restoration was affected by root region, type of post and type of cement used


Article
Assessment of Enamel Surface after Debonding of Different Types of Esthetic Brackets (An In Vitro Study)

Authors: Ghaith M. Hasan غيث حسن --- Dhiaa J. N. Al-Dabagh ضياء جعفر الدباغ
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2016 Volume: 28 Issue: 4 Pages: 162-167
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Debonding orthodontic brackets and removal of residual bonding material from the enamel surface include critical steps that may cause enamel damage. The aim of the present study was to evaluate and compare the site of bond failure and enamel surface damage after debonding of three types of esthetic brackets (composite, ceramic, sapphire) bonded with light cure composite and resin-modified glass ionomer adhesive.Materials and methods: Seventy two maxillary premolars teeth were divided into three groups each group consisted of 24 teeth according to the type of brackets. Each group was subdivided into two subgroups (12 teeth for each) according to the bonding material that was used. After 7 days of bonding procedure, the brackets were debonded using specifically designed debonding device in which the brackets were debonded by a debonding pliers to simulate the actual clinical debonding procedure. Instron Universal testing was used to apply the debonding force on the debonding pliers which transferred to the bracket. The teeth and the brackets were examined with a 10X magnifying lens to evaluate the site of failure. After the removal of residual adhesive, stereomicroscope was used to evaluate enamel surface damage.Results: The most common type of bond failure was cohesive failure (Score II) in all esthetic brackets. While enamel cracks (scale I) were found to be the most type of enamel damage. Chi- square showed non-significant differences among different types of esthetic bracket bonded with same type of adhesive and between the same types of brackets (ceramic, sapphire) bonded with the two types of adhesive. On the other hand, there was significant difference between composite brackets subgroups bonded with the two adhesives.Conclusion: The bond failure mostly within the adhesive itself and higher enamel damage was resulted from mechanical debonding of these esthetic brackets.


Article
Mechanical Properties Enhancement of Conventional Glass Ionomer Cement by Adding Zirconium Oxide Micro and Nanoparticles
تحسين الخواص الميكانيكية لمادة العزل المزججة الاسمنتية التقليدية باضافة دقائق اوكسيد الزركنيوم المايكروية والنانوية

Author: Ali N. Alobiedy
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2019 Volume: 25 Issue: 2 Pages: 72-81
Publisher: Baghdad University جامعة بغداد

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Abstract

The aim of this work is to enhance the mechanical properties of the glass ionomer cement GIC (dental materials) by adding Zirconium Oxide ZrO2 in both micro and nano particles. GIC were mixed with (3, 5 and 7) wt% of both ZrO2 micro and nanoparticles separately. Compressive strength (CS), biaxial flexural strength (BFS), Vickers Microhardness (VH) and wear rate losses (WR) were investigated. The maximum compression strength was 122.31 MPa with 5 wt. % ZrO2 micro particle, while 3wt% nanoparticles give highest Microhardness and biaxial flexural strength of 88.8 VHN and 35.79 MPa respectively. The minimum wear rate losses were 3.776µg/m with 7 wt. % ZrO2 nanoparticle. GIC-containing ZrO2 micro and nanoparticles is a promising restorative material with improved mechanical properties expect wear rate losses.

ان الهدف من هذه الدراسة هو تحسين الخواص الميكانيكية لمادة العزل المزججة الاسمنتية (المستخدمة كحشوات للاسنان) من خلال اضافة دقائق اوكسيد الزركنيوم المايكروية و النانوية. تم خلط مادة الاسمنت الزجاجية مع دقائق اوكسيد الزركنيوم بالنسب (3 و5 و7)% وزنية ومن كل حجم على حدة. أجريت اختبارات قوة تحمل الضغط، قوة المرونة ثنائية محور الحمل، الصلادة السطحية المايكروية بالاضافة الى معدل تاكل المادة. اظهرت النتائج ان اعلى قيمة لقوة تحمل الضغط كانت 122.31 ميكاباسكال لنسبة ال 5% للحجم المايكروي بينما اعلى قيم لقوة المرونه ثنائية محور الحمل و الصلادة السطحية المايكروية 88.8 رقم صلادة فيكرز و 35.79 ميكاباسكال على التوالي للنسبة 3% النانوية. في حين ان اقل معدل للتاكل كان لنسبة ال 7% النانوية والتي كانت 3.776 مايكروغرام متر. هذه النتائج تبين ان استعمال مادة اوكسيد الزركنيوم حسنت من الخواص الميكانيكة للمادة الاساسية ماعدا نتائج اختبار معدل التاكل.


Article
Investigating Some of the Mechanical Properties of Glass-Ionomers Cements Modified with ZnO and TiO2 Nanoparticles
دراسة بعض الخصائ ص الميكانيكية لأسمنت الأيونومر الزجاجي المطورة بجسيمات اوكسيد الزنك واكسيد التاتونيوم النانوي ة

Author: Rafid M. Al Badr رافد مصطفى بدر
Journal: Diyala Journal For Pure Science مجلة ديالى للعلوم الصرفة ISSN: 83732222 25189255 Year: 2019 Volume: 15 Issue: 04 Pages: 85-97
Publisher: Diyala University جامعة ديالى

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Abstract

Glass-ionomer cement (GIC) is one of the common restorative materials, but they exhibit relatively low mechanical properties. The aim of this study is the improvement of the properties of glass ionomer cement by incorporation of (1, 3 and 5wt.%) of different types of ZnO and TiO2 nanoparticles. Two conventional types of GIC Luting Cement were used (Ketac Cem radiopaque and Polyalkenoate Cement). Flexural strength and diametral tensile strength were calculated after 24 hr. and 3 weeks according to ISO4049. The results show a slight increase in flexural strength of glass ionomer cement, after adding 1 wt.% of both ZnO/NPs and TiO2/NPs, while the increase in flexural strength was significant at 3wt.% which reached 14% and 15.71% for ZnO/NPs and TiO2/NPs respectively for Ketac Cem radiopaque and reached 4.79% and 8.59% for Polyalkenoate Cement at the same ratio. Also, the flexural strength value increased after 3 weeks for all incorporation weight percentages. The modified tested cement also exhibited higher diametral tensile strength after 3 weeks, than that recorded in 24 hr for all concentrations (1, 3 and 5wt.%) of ZnO and TiO2 nanoparticles, in addition to the increase in diametral tensile strength after the incorporation of nanoparticles with glass ionomer cement. Within the limits of this study, a considerable increase in flexural strength and diametral tensile strength was observed with ZnO and TiO2 nanoparticles incorporations in 3wt% by weight. Furthermore, an increase in these properties after 3-week storage in distilled water was noticed.

أسمنت الأيونومر الزجاجي هو عبارة عن مادة مرممة تستخدم في طب الأسنان كمادة حشو وأسمن ت لصق، وخصائصهالميكانيكية منخفضة نسبيًا. الهدف من الدراسة تحسين الخصائص الميكانيكية لأسمنت الأيونومر الزجاجي من خلال اضافةجسيمات ZnO و 2TiO النانوية بنسب وزنية مختلفة ) 1 ، 3 و 5 % Wt (. تم استخدام نوعين من أنواع GIC Luting Cement المتوفرة في الاسواق ) Ketac Cem radiopaque و Polyalkenoate Cement (. تم قياس قوة الانثناء وقوةالشد المحوري للاسمنت المحضر بعد 24 ساعة و 3 أسابيع ، وفقًا للمواصفة ISO 4049 . تظهر النتائج زيادة طفيفة في قوةالانثناء في أسمنت الأيونومر الزجاجي المطور مع إضافة 1% لكل من ZnO / NPs و / NPs 2TiO ، ويزداد بشكل كبيرعند النسبة 3 % حيث تصل هذه الزيادة الى 14 % إلى 15.71 % ، على التوالي بالنسبة للمواد النانوية المستخدمة في Ketac Cem radiopaque كذلك تزداد النسبة لتصل الى 4.79 % إلى 8.59 % ل Polyalkenoate Cement . أيضا، تم زيادةقيمة قوة الانثناء بعد غمرها بالماء المقطر 3 أسابيع لجميع المواد المستخدمة. كذلك أظهر الأسمنت المعدل ارتفاع في قيمةقوة الشد المحوري بعد 24 ساعة و 3 أسابيع من غمرها بالماء لكل تركيز ) 1 و 3 و 5%( من جسيمات ZnO و 2TiOالنانوية، وخصوصا بالنسبة الوزنية 3 % للإسمنت الأيونومر الزجاجي المعدل. اظهرت النتائج زيادة كبيرة في قوة الانثناءوقوة الشد المحوري مع دمج جسيمات ZnO و 2TiO النانوية بنسبة 3 % بالوزن. علاوة على ذلك ، فقد لوحظ زيادة في قيمهذه الخصائص بعد تخزينه ا 3 أسابيع في الماء المقطر.

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