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Article
Evaluation of shear bond strength of brackets bonded to fluoride-treated enamel surfaces: An in vitro study

Authors: Ahmad A ABDUL-MAWJOOD --- Khidair A SALMAN
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2001 Volume: 1 Issue: 3 Pages: S343-S352
Publisher: Mosul University جامعة الموصل

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Abstract

Enamel decalcification is a well-recognized problem associated with orthodontic treatment with fixed multibanded appliances. Several methods have been proposed to minimize the incidence and severity of white spot decalcification around brackets. The present study is concerned with the evaluation of the effect of different topical fluoride gels, applied before and after etching on the shear bond strength of directly bonded orthodontic brackets. The sample consisted of (70) human upper first premolars distributed to (7) groups: group A served as a control; groups B1, C1, andDl received, for (4) minutes prior to etching, a topical application of neutral sodium fluoride gel (1.1%), sodium monofluorophosphate gel (1.2%), and acidulated phosphate fluoride gel (1.23%) respectively. Groups B2, C2, and D2, on the other hand, were treated, for (4) minutes after etching, with topical application of neutral sodium fluoride gel (1.1%), sodium monofluorophosphate fluoride gel (1.2%), and acidulated phosphate fluoride gel (1.23%) respectively.The brackets were loaded under shear to failure using Universal Compression Machine Apparatus. The shear strengths were recorded in Megapascals.The results of the present study showed that the application of fluoride gels for (4) minutes before and after etching did not alter the shear bond strengths of directly bonded orthodontic brackets, when compared with the control group, for all groups except for group D2 in which the topical application of acidulated phosphate fluoride gel for (4) minutes after etching has resulted in a significant reduction in shear bond strength and severity of white spot decalcification around brackets.

Keywords

Bond strength --- fluoride


Article
Shear bond strength of the Iingually and buccally bonded brackets via three composite systems

Authors: Hussain A Obaidi B.D.S., M.Sc *. د. حسين العبيدي --- Naser A Khayyat B.D.S., M.Sc د. نصير خياط
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2005 Volume: 2 Issue: 2 Pages: 157-166
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

This study aimed to determine and compare the shear bond strength of linguallybonded brackets via: Two—paste composite (Orthodontic Mix Bonding System), No —mix composite [Orthodontic Bonding System (No—mix)] and Light—cured composite( Transbond XT .)Thirty extracted upper first premolars for orthodontic request were used for thisinvestigation. The teeth were divided into three groups; each of which consisted of l0teeth. The lingual surface of the tooth used to evaluate the lingual bond strength andthe buccal surface of the same tooth utilized to evaluate the buccal bond strength. Foreach group of teeth investigated to determine the lingual and buccal bond shearstrength, using one type of composite system for each group .The lingually bonded and buccally bonded samples were subjected to shearforce using the universal compression testing machine apparatus. The lingual andbuccal shear bond strengths were recorded and converted into Mpa and the data werestatistically analyzed .The results showed the lingual shear bond strength insignilicantly less than thatof buccal shear bond strength regarding the Orthodontic Mix Bonding System andOrthodontic Bonding System (No—mix), and the lingual shear bond strength wassignificantly less than the buccal shear bond strength regarding Light—curedcomposite (Transbond XT), The lingual and buccal shear strengths of the bondedbracket via Orthodontic Mix Bonding System were the highest than the shear bondstrength of the other composite systems


Article
The effect of temperature variation of composite orthodontic adhesive on shear bond strength (In vitro comparative study)

Authors: Gheyath S. Al-Naqash غيث النقاش --- Mushriq F. Al-Janabi مشرق الجنابي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: 1 Pages: 96-100
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The temperature of the adhesive may influence the chemical reactions and consequently interferewith bonding procedures, compromising the quality and durability of the bonding. This in vitro study was designed toassess and compare the effect of temperature variation in an orthodontic office on the shear bond strengths andthe types of bond failure of two composite adhesive systems, a No-Mix and Light Cure adhesive systems.Materials and Methods: Ninety sound human upper first premolars were collected and divided randomly into sixequal groups, three groups for One-Step and three groups for Light Cure adhesive systems with 15 teeth each. Aftera careful and standardized bonding procedure, the samples were subjected to shear tests using a Tinius-OlsenUniversal Testing machine. After debonding, the bracket bases and the corresponding teeth were examined under astereomicroscope with a magnification of 20X to determine the predominant failure type.Results: The results of this study showed that for the One-Step system temperature variation has a non-significantdifference, while for the Light Cure system the refrigerated adhesive has significant higher shear bond strength. Therewas a non-significant difference in the failure site for both of the adhesive systems used in the study.Conclusion: In short, temperature variation affected Light Cure adhesive system more than No-Mix adhesive system


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

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: 1 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
Evaluation of the Bond Strength of Three Soft Lining Materials to Acrylic Resin Denture Base

Authors: Asmaa A Abid Al-Kadder --- Munther N. Kazanji
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2012 Volume: 12 Issue: 1 Pages: 57-65
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: The aims of this study were to evaluate the effect of different surface treatments and different periods of water storage on tensile bond strength of three soft lining materials. Materials and me-thods: Two hundred sixty four (264) specimens have been prepared. Surface treatments used for bond-ing Molloplast – B liner included roughening acrylic surface with bur, and treatment with primo adhe-sive. For bonding Bony plus liner, roughening acrylic surface with bur, treatment with liner’s liquid and combination of both treatments have been evaluated. For GC Reline liner, roughening acrylic sur-face with bur has been evaluated.Befor tensile bond testing of molloplast-B liner’s specimens they were stored for(1 day or 1 month or 4 months), while Bony plus and GC Reline liners’specimenes were stored for(1 day or 1 week or 1 month) and then tested. Results: The results showed that roughening acrylic surface had an insignificant effect on (TBS) of GC Reline liner and Bony plus liner (although these materials showed cohesive failure). Bony plus liner’s liquid treatments had significant improve-ment in (TBS) of this liner. Different periods of water storage had insignificant effect on (TBS) of Mol-loplast-B liner and GC Reline liner, but (TBS) of Bony plus liner showed significant increasing after 1-month water storage. Conclusion: From the results of this study we can concluded that surface treat-ment to acrylic base improved tensile bond strength of soft lining material ,and the effect of water sto-rage on bond strength differed with different types of soft lining materials.


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
Evaluation of the effect of intermediate agents on the shear bond strength of repaired aged silorane resin composite

Authors: Hanaa A. Saleh هناء صالح --- Luma M. Baban لمى بابان
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: 4 Pages: 8-13
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The aim of this study was to evaluate the bonding effect of different intermediate agents on the bondstrength of silorane resin composite (Filtek™ P90,3M ESPE) that repaired by either silorane (Filtek™ P90) ormethacrylate based resin composite (Filtek™ Z250,3M ESPE)Materials and Methods: Eighty specimens of resin composite prepared by filling silorane (Filtek™ P90) into a retentivecavity (6mm in diameter and 2mm in depth) of acrylic mold. The composite were polymerized, water stored at 37°Cfor one week. Their surface were finished with medium (violet) super-snap disks then rinsed in ultrasonic cleaner.Repair was performed with either silorane (Filtek™ P90) or methacrylate based composite (Filtek™ Z250) by usingseveral intermediate agents which include (P90 System Adhesive, Adper Scotchbond Multipurpose and Clearfilrepair kit).The shear bond strength (crosshead speed 0.5 mm/min) was measured after an additional water storageof 24 hour.Results: Statistical analysis of data revealed that intermediate agents enhanced the bond strength significantly(p<0.001).The highest shear bond strength were determined for Clearfil repair kit and P90 System Adhesive whichwere significantly higher than the control (p<0.001). Adper Scotchbond Multipurpose enhanced the bond strengthsignificantly than the control but it was significantly lower than the other adhesive systems (p<0.001).Conclusions: The Clearfil™ Repair kit and P90 System Adhesive were the most effective intermediate agents for repairof silorane restoration with both silorane and methacrylate repair materials.Use of Adper Scotchbond Multipurposeresulted in bond strength which is considered clinically inadequate


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

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