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Article
COMPARISON STUDY OF THE SHEAR BOND STRENGTH BETWEENPOLYETHER AND ADDITION SILICONE IMPRESSIONMATERIALS

Author: Saad F. Oboudi
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2009 Volume: 12 Issue: 3 Pages: 56-63
Publisher: Al-Nahrain University جامعة النهرين

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Abstract
The impression material is used mainly in the area of removable partial and complete denture
and in the construction of inlays, crowns and bridges. They are used also in dental laboratories for
duplicating master casts.
Recent studies have evaluated the bond strength of selected impression materials. This research
was performed to study the shear bond strength of impression materials to tray by testing forty
samples, each of which consisted of two blocks of acrylic with the impression material sandwiched
between them. Tray adhesive was used to increase adhesion between impression material and
custom tray. Also this research showed that by the use of perforation impression materials adhere
firmly to the impression trays. Therefore perforation - adhesive combination gave acceptable
results.
Experimental results indicated that polyether impression material showed higher shear bond
strength values to cold-cure acrylic than addition silicone impression material for both control and
perforated samples without adhesive application. The shear mean bond strength values of polyether
to the tray material after adhesive application were decreased. While, the shear mean bond strength
increased significantly when addition silicone was used with the adhesive and with the combination
samples.


Article
The Effects of Acetic Acid and Chlorhexidine Gluconate as a Cavity Cleanser on the Shear Bond Strength of Compomer Restorations

Author: Dr. Raghad A. Mohammed.B.D.S, M.Sc.* د.رغد محمد
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2009 Volume: 6 Issue: 1 Pages: 28-31
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Bonding of restorative materials to tooth structure has become one of the prime objectives of modern dentistry. The purpose of this in vitro study was to evaluate andcompare the shear bond strength of compomer material to dentin washed with three cleanser agent. Thirty freshly extracted adult human maxillary firs,, premolars teeth were utilized in this study. Each tooth was sectioned horizontally exposing the dentin surface. According to the type of cleanser agent used to wash the dentin surface; the teeth were divided into three groups often teeth each: Group I chlorhexidine cleanser with compomer; Group II acetic acid with compomer; and Group III distal water with compomer. The measurement for evaluation the shear bond strength of compomer to dentin by using Zwick universal testing machine. The results showed that higher significant different between group I and group III also between group II and group III; however< there is no significant difference between group I and group II. This present in vitro study concludes that the shear bond strength of compomer material to dentin can be enhanced by washing the exposed dentin with cleanser agents chlorhexidine and acetic acid instead of distal water.


Article
The shear bond strength of moisture insensitive orthodontic bonding.

Author: Ne’am R. Al–Saleem
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2007 Volume: 7 Issue: 9 Pages: 61-65
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: To assess the effect of water contamination on the shear bond strength of moisture insensitive Fuji Lc. glass ionomer and to compare it with the shear bond strength of (transbond) light cure composite. Materials and methods: Sixty extracted human premolar were cleaned and dried and embedded in cylinders filled with dental stone and the teeth were divided into three groups (20 teeth of each) which were etched and washed and dried the teeth in group 3 were slightly moistened in a cotton pellet and then the brackets were bonded to the teeth according to the manufacture instructions. Group1: using light cure composite (transbond); Group2: using glass ionomer cement (Fuji Lc.) in dry condition; Group3: using glass ionomer cement (Fuji Lc.) in moist condition. The shear bond strength was measured using instron mechanical test machine. Statistical analysis including descriptive statistics were applied to the results and then the findings were compared among the three groups using ANOVA and Duncan tests. Results: Light cure composite (transbond) had the highest shear bond strength followed by Fuji Ortho. Lc. (moist condition) and then Fuji Lc. (dry condition), which had the significant lowest shearbond strength. Conclusions: Transbond light cure composite had the highest shear bond strength. The presence of moisture enhances the shear bond strength of light cure glass ionomer cement (Fuji Lc.).


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
Shear bond strength of different lingual buttons bonded to wet and dry enamel surfaces with resin modified glass ionomer cement (in vitro comparative study)

Authors: Hiba M. Alkhateeb هبة محمد الخطيب --- Eman I. Al-Sheakli ايمان الشيخلي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 1 Pages: 146-152
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This study was aimed to investigate the effect of three lingual button (Nickel free / rectangular base,Nickel free / round base and Composite) and bonding environment, wet and dry enamel surface, on: the shearbond strength (SBS) of light and self-cured Resin Modified Glass Ionomer Cements, and the debonding failure sites.Materials and method: One hundred twenty no-carious, free of cracks maxillary first premolar teeth were selected.Three types of orthodontic lingual buttons were used in this study: Nickel free / rectangular base, Nickel free / roundbase and Composite buttons. The teeth were divided into two groups of sixty teeth each. One group was used fortesting the chemically cured GC Fuji Ortho Resin modified Glass Ionomer (RMGIC), while the other was used fortesting the light cured GC Fuji Ortho LC RMGIC. Each was further subdivided into two subgroup; thirty teeth werebonded to wet enamel surface while the other was bonded after drying the enamel surface. Then each ten teethfrom each subgroup were bonded with only one type of buttons. The sample was tested for bond strength using theuniversal testing machine and the Adhesive Remnant Index (ARI) was inspected under the stereomicroscope.Results:The highest (SBS) values were obtained in the Nickel free / round base button with both types of RMGIC in wetand dry environment as revealed by ANOVA test. While t-test revealed that both systems of RMGIC yield relativelylower values of (SBS).Conclusions:The GC Fuji Ortho RMGICs resist shear force in dry better that in wet environment.Nickel free / roundbase buttons give the greatest shear bond strength among the three types of button.The composite buttons givegreater bond strength in dry than in wet environment with both GC Fuji Ortho and GC Fuji Ortho LC RMGICs


Article
Aging effect of different types of composite resin restoration on shear bond strength to different orthodontic adhesives with sapphire bracket (In vitro comparative study)

Authors: Linda B. Jabbar لندا جبار --- Fakhri A. Ali فخري عبد علي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 2 Pages: 144-149
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This study was performed to determine the effect of aging of different types of composite materialrestorations on: Shear bond strength (SBS) to light cure and no mix chemical cure orthodontic adhesives withsapphire bracket and the debonding failure sites.Materials and methods: One hundred forty four composite disks were made from three different composite resinmaterials which are: 3M Filtek Z250, 3M filtek Z350 and 3M Valux plus, each group with (48) disks each, thenaccording to the duration of storage each group was subdivided into two equal groups one of them stored for oneday and the other was stored for one month, then each group was further subdivided into two equal subgroups with(12) disks each one bonded with light cure orthodontic adhesive and the other with no mix chemical cure adhesive.The sample was tested for bond strength using the universal testing machine and the Adhesive Remnant Index (ARI)was inspected under the stereomicroscope.Results: The results revealed that there was a highly significant difference among the three types of compositematerials bonded with light cure orthodontic adhesive as showed by ANOVA test, while the T test showed that therewas no significant difference between the two storage durations and also between the two orthodontic adhesivesfor both Filtek Z250 and Valux plus.Conclusions: The highest (SBS) values were obtained from Filtek Z350 samples than other two types of composite. Allthe samples stored for one day showed higher values of (SBS) than those stored for one month


Article
Evaluation of shear bond strength between thermosens as relining material and different denture base materials

Author: Ghazwan Adnan Alkinani غزوان عدنان الكناني
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 4 Pages: 28-31
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Denture relining is the process of resurfacing of the tissue side of the ill fitting denture, the bond strengthat the relining-denture base interface is most important for denture durability.The aim of present study was toevaluate the shear bond strength between the thermosens as relining material and different denture base materialsthat bonded by thermo fusing liquid. As this corrective procedureis the common chair side procedure in the dentalclinic.Material and method: Sixty samples were prepared and divided into three main groups according to the type ofdenture base materials.Group (A) referred to the heat cure acrylic samples which consisted of 20 samples. Group (B)referred to the high impact acrylic samples which consisted of 20 samples. Group (C) referred to the thermosenssamples which consisted of 20 samples. All groups then subdivided into two groups; each one consists of 10 samples,according to the surface roughness: (A1, B1and C1 for groups with surface roughness and A2, B2 and C2for groupswithout surface roughness). Each sample consisted of two similar parts represent the denture base material eachpart of the sample was designed with dimensions of (70mm X 12mm X 5mmlength, width and depth respectively)having a stopper of depth 3mm. One part of the sample was placed on the other in a manner thatleaving a spacebetween them of dimensions (12mm X 12mm X 3mm length, width and depth respectively) to sandwich the reliningmaterial.Results: The results showed that the thermosens samples had the highest value of shear bond strength followed bythe high impact acrylic samples, then heat cure acrylic samples which had the lowest value of shear bond strength.The results of present study showed that rough samples had reducedshear bondstrength in comparison with thesmooth samples of the same denture base material

خلفیة : تبطین طقم الأسنان ھي عملیة اضافة طبقةالى سطح الطقم المواجھ لانسجة الفم الساندة للطقم ، ان قوة الالتصاقبینمادة التبطین و مادة قاعدة الطقم ھي الأكثر أھمیة بالنسبةلمتانةالطقم. الھدف من الدراسة الحالیة ھو تقییم قوة الالتصاق بین مادة الثیرموسینس كمادة تبطین و مواد قاعدة طقم مختلةتم لصقھا بواسطة سائل الثیرمو فیوشن. و ھذه العملیة التصحیحیةھي من العلاجات الشائعة في عیادة الأسنان .تشیر الى عینات الاكریلیك المعالج بالحرارة التي تتكون ( A ) المواد و طریقة العمل: تم إعداد ستین عینة و تنقسم إلى ثلاث مجموعات رئیسیة وفقا لنوع مواد قاعدةالطقم . المجموعةتشیر إلى عینات الثیرموسینس التي تتكون من 20 عینة . جمیع ( C ) تشیر إلى عینات الاكریلیك عالیة التاثیر التي تتكون من 20 عینة . المجموعة ( B ) من 20 عینة . المجموعة،A تشیر الى مجموعات العینات ذات الاسطح الخشنة و ( 2 (B1 ,C1 ،A المجموعات تم تقسیمھا إلى مجموعتین ؛ تتكون كل مجموعة من 10 عینات ، وفقا لخشونة سطح العینة: ( 15مم X 12 مم X تشیر الى مجموعات العینات ذات الاسطح الصقیلة. تتكون كل عینة من جزأین متماثلین تمثل مادة قاعدة الطقم تم تصمیم كل جزء من العینة مع أبعاد ( 70 مم (C2, B2X 12 مم X طول وعرض وارتفاع على التوالي)مع وجود عتبة من ارتفاع 3مم . یوضع جزء واحد من العینة على الآخر بطریقة تترك مسافة بینھما لتملئ بمادة التبطینبالأبعاد ( 12 مم3مم طول وعرضوارتفاع على التوالي).النتائج: أظھرت النتائج أن عینات الثیرموسینس كانت أعلى قیمة لقوة الالتصاق تلیھا عینات الاكریلیك عالیة التأثیر، ثم عینات الاكریلیك المعالج بالحرارة التي كانت أقل قیمة من قوةالالتصاق. وأظھرت نتائج الدراسة أن قوة الالتصاق قلت فیالعینات ذات الاسطح الخشنة بالمقارنة مع العینات ذات الاسطح الصقیلة من نفس مادة قاعدة الطقم .مفتاح الكلمات:الثیرموسینس وسائل الثیرموفیوشن و قوة الالتصاق.


Article
Shear bond strength of endodontic sealers to dentin with and without smear layer and gutta percha (An in vitro study)

Authors: Rana Kadhim Hasan رنا كاظم حسن --- Majida K. Al-Hashimi ماجدة الهاشمي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 4 Pages: 86-89
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The bond strength of root canal sealers to dentin and gutta-percha seems to be an important propertyfor maintaining the stability of root canal filling, which potentially influences both leakage and root strength. Theobjective of this, in vitro, study was to evaluate the shear bond strength of three different endodontic sealers (Gutta-Flow, AH Plus, Apexit Plus) to dentin, in the presence and absence of the smear layer and gutta percha.Material and Methods: After slicing off the occlusal 2mm of 60 extracted human maxillary premolar teeth, theexposed dentin served as the tested surfaces; the teeth were fixed with cold cure acrylic, and were divided into twogroups according to the smear layer presence, group A without smear layer, when dentin surfaces were irrigatedwith EDTA 17% followed by distilled water then subdivided into 3 subgroups according to the type of sealer used;group B when dentin surfaces were washed with distilled water only, then subdivided into 3 subgroups. Thirty samplesof gutta-percha were prepared and named as group C which was subdivided into 3 subgroups. Five mm longsection of polyethylene tubes were placed on the dentin or gutta percha surfaces and filled with freshly mixedsealer. After one week, all the samples were tested for shear bond strength by the Instron Universal Testing Machineat a cross head speed of 0.5 mm/min. The data was calculated in MPa and was statistically analyzedResult: There was a highly significant difference in the shear bond strength (P < 0.05) in comparison among the testedgroups, GuttaFlow showed non-significant difference in bond strength to dentin with and without smear layer, whileAH Plus and Apexit Plus showed a high significant difference.Conclusions: AHPlus showed the highest shear bond strength in all the tested samples, while GuttaFlow was the least.Additionally, AH Plus and Apexit Plus shear bond strengths were affected by the smear layer removal, whileGuttaFlow was not.

صیة مھمة للحفاظ على ثبات حشوة قناة الجذر الذي بدوره یؤثرعلى تسرب و قوة الجذر. Gutta-percha أن لقوة الرابطة لسدادات قناة الجذرالى عاج السن وو عاج السن بوجود اوعدم (AH Plus, Gutta-FlowApexit Plus,) كان الغرض من ھذه الدراسة تقییم قوة الترابط القصي بین ثلاثة انواع من السدادات اللبیة المختلفةبعد قطع 2ملمیتر من تاج 60 سن من أسنان الإنسان(الضواحك العلیا) . تم تثبیت الأسنان في مادة الاكریلیك ، و قسمت .Gutta-percha و ال Smear layer وجود طبقة ال.Smear layer الى مجموعتین وفقا لوجود طبقة ال(AP-) %17 یلیھ الماء المقطر وقسمت إلى 3مجموعات فرعیة وفقا لنوع السدادة المستعملة EDTA على سطح عاج السن مع غسل بمادة Smear layer المجموعة (أ) بدون.D, AH-D, GF-D. APD-S, AHD-S, GFD-S)( المجموعة (ب) غسل سطح عاج السن بالماء المقطر فقط ثم قسمت إلى 3 مجموعات فرعي.(AP-G, AH-G, GF-G) أعدت لتكون المجموعة (ج)وقسمت إلى 3 مجموعات فرعیة (Gutta-percha) ثلاثونعینة مناختبار قوة الرابط القصي تم بعد اسبوع . . Gutta-percha استعمل انبوب بطول 5 ملم من البولي اثیلین بسداده مخلوطة حدیثا ووضع على سطح عاج السن أو السجل فرق معنوي غیر ملحوظ في قوة الترابط مع عاج السن بوجود Gutta-Flow. تم حساب البیانات بوحدة المیغا باسكال و تم تحلیلھا إحصائیاً . أظھرت النتائج فرقا معنویا كبیراسجلوا فرقاً معنویاً عالیاً. Apexit Plus و AH Plus بینما Smear layer اوعدم وجود التأثرت Apexit plus و AH Plus الاقل بینھم . وقوة الربط القصي لل Gutta-Flow اظھر اعلى قوة ربط قصي في جمیع العینات بینما كان AH Plus : الاستنتاج النھائيفلم تتأثر.


Article
Evaluation of shear bond strength of zirconia to tooth structure after different zirconia surface treatment techniques

Authors: Reem Mounes Dawood ريم مؤنس داود --- Adel F. Ibraheem عادل فرحان ابراهيم
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2015 Volume: 27 Issue: 1 Pages: 77-85
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This study aimed to evaluate the effect of zirconia different surface treatments (primer, sandblast with50μmAl2O3, Er,Cr:YSGG laser) on shear bond strength between zirconia surface and resin cement.Material and methods: Sixty presintered Y-TZP zirconia cylinder specimens (IPS e.max ZirCAD, Ivoclar vivadent) will befabricated and sintered in high temperature furnace of (1500 C for 8 hours) according to manufacturer’s instructionsto the selected size and shape of (5mm. in diameter and 6mm in height). All specimens were ground flat using600.800.1000.1200, aluminum oxide abrasive paper to obtain a standardized surface roughness. Surface roughnessvalues were then recorded in μm using surface roughness tester (profilometer) to obtain a standardized data baseline for all samples. The specimens were then randomly divided into three main groups (n=20); group A: no surfacetreatment (control group), group B: specimens in this group treated with 50μm Al2O3 and group C: specimens in thisgroup treated with Er,Cr:YSGG laser.Sixty sound human premolars were used in this study, after construction of acrylic blocks, the occlusal surface of theteeth were ground flat, with diamond cutting disk to obtain a flat dentine surface .Prior to cementation of zirconia cylinders to tooth specimens subgroups (A1,B1,C1) will receive a coat ofmetal/zirconia primer and left to react for three minutes, while the subgroups (A2,B2,C2) were left undisturbed.Bonding surface of zirconia cylinder was then luted with SpeedCEM self adhesive resin cement under a static load of2Kg. placed on the vertical arm of the surveyor and allowed to auto cure for 4minutes.The final cementedspecimens were then stored in distilled water at room temperature for 24hours.All specimens were subjected to shear loading force in a universal testing machine at crosshead speed of 1mm/min.The shear bond strength values were analyzed statistically with one-way ANOVA; the fractured surfaces of zirconiacylinders were examined with a stereo-microscope to observe the failure mode.Results: The air borne-particle of 50μm followed by primer application showed significantly the higher bond strengththan other groups.Conclusion: Within the limitation of this study, the results showed that sandblasting the bonding surface of zirconiumcylinders with 50μmAl2O3 produced the highest values of shear bond strength , also the use of primer enhancedshear bond strength as well


Article
The Effects of Enamel Protective Agents on Shear Bond Strength After Rebonding of Stainless Steel Orthodontic Bracket (An in Vitro Study)

Authors: Ruaa Ali K. Al-Sarkhi --- Dheaa H. Al-Groosh
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2017 Volume: 29 Issue: 1 Pages: 170-176
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Bracket rebonding is a common problem in orthodontics which may result in many drawbacks. The aims of this study were to evaluate the effects of application of two enamel protective agents “Icon” and “ProSeal” on shear bond strength before and after rebonding of stainless steel orthodontic brackets using conventional orthodontic adhesive and to assess the site of bond failure.Materials and methods: Fifty sound extracted human upper first premolar teeth were selected and randomly divided into two equal groups; the first time bonding and the rebonding groups (n=30). Each group was subdivided into control, Icon and ProSeal subgroups. The enamel protective agents were applied after etching (preconditioners). Shear bond strength before and after rebonding of stainless steel brackets were assessed using the Universal testing machine and the adhesive remnant index was used to find out the bond failure site using a stereomicroscope. Then the results were statistically analyzed using one-way ANOVA analysis test and T-test.Results: There were no significant differences in the shear bond strength mean values in either group or their corresponding subgroups. Forty percentage of the bond failure in ProSeal groups occurred away from the enamel where 75% of those were at the enamel protective agents/adhesive interface.Conclusions: The application of Icon and ProSeal did not compromise the shear bond strength and the application of the ProSeal may protect the enamel surface from trauma (cracks, chipping or detachment).

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