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Article
The shear bond strength of an immediate and delay repaired light-cure composite restoration (In vitro study)

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Abstract

Background: Defects in composite resin restoration whether discovered at the time of placement or associated withold composite resin restoration could be repaired without replacing the entire restoration. This in vitro study wasconducted to determine and compare the shear bond strength of an immediate and delay repaired light curedcomposite restoration.Materials and methods: Eighty acrylic blocks (25x25x15 mm) were constructed from cold cure acrylic resin; each onecontained an acrylic hole (6mm diameter and 3mm depth) that filled with Helioprogress composite resin. The surfacelayer of the composite resin samples was light cured through plastic strip, abraded by finishing discs and rinsed withdeionized distilled water for 15 sec. The eighty specimens were divided randomly into two groups according to thestorage time in deionized distilled water before the repair:Group I: Stored for 15 min. (Immediate repair group)Group II: Stored for 1week. (Delay repair group)Both groups were subdivided into 4 subgroups according to the surface treatment they received:Subgroup 1: No surface treatment (control)Subgroup 2: 37% phosphoric acid etchant (15 sec.)Subgroup 3: Heliobond (light activated for 20 sec.)Subgroup 4: 37% phosphoric acid and Heliobond.Repair was done by using a standardized translucent plastic straw (3mm diameter and 6mm length) and was filledHelioprogress composite resin and light cured for 40 sec. in four directions. All the specimens were stored in deionizeddistilled water for 24 hr. testing was done by the Zwick testing machine by applying shearing force with speciallydesigned chisel-shape rod. Data obtained were statistically analyzed using analysis of variance test and t-test.Results: The results showed very highly significant difference between the similar subgroups in group I vs. group II andthere was non-significant difference between subgroup 1 vs. 2 and between subgroup 3 vs. 4.Conclusion: Delaying the repair procedure for 1 w resulted markedly reduced the bond strength, the surfacetreatment with 37% phosphoric acid slightly reduced the bond strength in the immediate repair while slightlyincreased it in the delay repair, Furthermore, the surface treatment with Heliobond fifth generation bonding agentmarkedly increased the bond strength in both repairs.

Keywords

Repair --- composite --- shear bond


Article
The Effect of Different Disinfectant Solutions on Shear Bond Strength of Acrylic Teeth to Flexible Denture Base Material

Author: Ihssan F Al-Takai
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2014 Volume: 14 Issue: 1 Pages: 145-152
Publisher: Mosul University جامعة الموصل

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Abstract

is to evaluate the effect of three different disinfectant solutions on shear bond strength of artificial acrylic teeth for retention to flexible denture base material at three different periods of time. Materials and Methods: The total number of samples was (60) divided into 4 groups according to the three chemical disinfectant solution which used and the control distilled water group: Group( I) vinegar group, Group( II) salt group , Group(III) Chlorohexidine group , Group (IV ) the control distilled water group, where each group was subdivided into three subgroups according to disinfection periods which are 1week, 1month and 3month where each group contain five samples. The samples of shear bond strength test were consist of acrylic teeth with T-shape design for retention attached to rod of valplast The test was performed using a Universal testing machine. ANOVA, DuncunP,Ps multiple range and Post Hoc Tests were carried out to determine the significant difference at p ≤ 0.01%. Results: The results appeared that control distilled water group has the highest value for the three periods of disinfection (1 week,1month,3months), while vinegar solution group has the least value. The results showed that there were significant differences between the four tested groups and also there were significant differences among all periods of time of disinfections. Conclusion: There was a significant difference of shear bond strength between artificial teeth and flexible denture base material after disinfection in the four disinfectant solutions for all periods of time of immersion. Vinegar group had highest effect on the bond strength while the distilled water group had the least effect after all periods of time of disinfections. Shear bond strength decreased with increasing the time immersion. The shear bond strength was lowest in chloherxidine group as the time of immersion increase when compared with the two other groups of disinfection solutions in this study.


Article
Assessment of shear bond strength of glass ionomer cement reinforced by different amounts of Hydroxyapatite

Author: Mohammed R. Hameed* BDS, MSc, PhD
Journal: Journal of the Faculty of Medicine مجلة كلية الطب ISSN: PISSN: 00419419 / EISSN: 24108057 Year: 2009 Volume: 51 Issue: 2 Pages: 151-154
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This study was done to assist bond strength of glass ionomer cement reinforced by different amount of Hydroxyapatite Materials and methods: In this study a hydroxyapatite materials were added to glass ionomer cement at different ratios; 10%, 15%, 20%, 25% and 30% (by weight) and the bond strength was detected by construction a cylinders from these mixed materials, constructed on exposed dentine of human extracted premolar teeth and by Zwick’s universal testing machine the bond strength were detected for these mixed materials.Results: Results showed that the glass ionomer cement reinforced by hydroxyapatite has higher bond strength than conventional glass ionomer cement and the hydroyapatite powder to glass ionomer cement powder ratio by weight best to be 25%. Conclusion: The addition of hydroxyapatite to conventional glass ionomer cement increased its bond strength to dentine.


Article
Effect of Time and Intensity of Curing Unit on Bond Strength of Stainless Steel Orthodontic Brackets (in vitro study)

Authors: Issam Merzah Abdullah --- Kasem Ahmed Abeas --- Lamis Khidher Mohammed --- Arkan Muslim Al-Azzawi
Journal: Medical Journal of Babylon مجلة بابل الطبية ISSN: 1812156X 23126760 Year: 2017 Volume: 14 Issue: 3 Pages: 532 -536
Publisher: Babylon University جامعة بابل

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Abstract

This in vitro study was aimed to evaluate the shear bond strength of orthodontic brackets that be cured with two types of light emitting diode (LED).Thirty extracted premolar teeth were divided arbitrarily into two groups. Each one of these groups consisted of 15 teeth framed in an acrylic block. After standard enamel etching procedure, each orthodontic brackets were cured on the first group of teeth with low intensity curing unit (1000-1200mW/cm2) for 20 second, the second group with high intensity curing unit (5000-6000 mW/cm2) for 6 second. For each bracket, its strength of shear bond was tested with a universal computerized testing machine. The results showed that brackets cured with low intensity LED produced the highest shear bond strengths (36.6 MPa) while with high intensity show (33 MPa) with no significant difference was found between them. the study can recommend the high intensity LED curing units as this can save time and decrease chair time.


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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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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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 Shear Bond Strength of Composite Resin Bonded to Dentin with Three Different Adhesive Systems

Author: Huda A. Abduallah هدى عباس عبد الله
Journal: Tikrit Journal for Dental Sciences مجلة تكريت لعلوم طب الاسنان ISSN: 20731213 Year: 2012 Volume: 1 Issue: 2 Pages: 13-18
Publisher: Tikrit University جامعة تكريت

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Abstract

Aim of the study to measure the shear bond strength of composite resin bonded to dentin with three different adhesive system.The buccal surfaces of 30 non-carious, intact, extracted upper premolar (Freshly extracted for orthodontic treatment), were grinded with 600 grit silicon carbide paper to expose dentin surface. the samples were divided into three groups: G1, 10 teeth were bonded with an acetone-base total-etch Prime&Bond NT G2, 10 teeth were bonded with an ethanol-base total-etch Excite. G3,10 teeth were bonded with an ethanol-and water-base total-etch Schotchbond 1. Shear bond strength is determined by using Instron testing machine.Results showed that excite adhesive system has statistically high significant increase in shear bond strength than Schotchbond 1.As conclusion; the lack of water in the adhesive may play a more important role than the type of solvent itself.


Article
Effect of different metal surface treatments and thermocycling on shear bond strength and microleakage of the flexible acrylic at Co/Cr interface

Authors: Ghazwan AA --- Nabeel AH نبيل عبد الفتاح هاطور
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2011 Volume: 23 Issue: special issue Pages: 10-14
Publisher: Baghdad University جامعة بغداد

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Background: Optimum bond strength at the valplast nylon (V.N.)-Co/Cr interface of a prosthesis is essential for thesuccess of that prosthesis. The junction between metal alloy and resin is an area of clinical concern. The aim of studyevaluation of the effect of different metal surface treatments and thermocycling on the shear bond strength andmicroleakage at the V.N.-Co/Cr interface.Material and method: A total No. of 140 samples were prepared and divided into two main groups according to thetype of test carried out. Group {A} referred to the metal samples of microleakage test which consists of 60 metalsamples, which were then subdivided into two groups; each one consists of 30 metal samples, according to thenumber of thermal cycles: (A1 subjected for 1000 thermal cycles and A2 for 3000 thermal cycles). Samples of eachgroup were then subdivided into three subgroups; each one consists of 10 metal samples, according to the type ofsurface treatment that was applied. Each group either had an air abrasion (A1a and A2a) or application of metalbonding agent (Metal Primer) (A1P and A2P) or combination of air abrasion and Metal Primer application (A1C andA2C). Each metal sample was divided into experimental half which received one type of surface treatment andcontrols half which was kept untreated. Group {B} referred to the metal samples of shear bond test which consists of80 metal samples. The samples of this group were then subdivided into two groups; each one consists of 40 metalsamples, according to the thermocycling: (B1 subjected for group without thermocycling and B2 for thermocycledgroup with 1000 cycles). Samples of each group were then subdivided into four subgroups; each one consists of 10metal samples, according to the type of surface treatment that was applied. Each group was either untreated (B1Uand B2U) or had an air abrasion (B1a and B2a) or application of metal bonding agent (Metal Primer) (B1P and B2P) orcombination of air abrasion and Metal Primer application (B1C and B2C). Before thermocycling the valplast nylon wasapplied to the metal samples.Result: The results showed that the metal samples treated with metal primer II had the highest value of shear bondand lowest value of microleakage followed by the metal samples treated with metal primer II combined with airabrasion. The metal samples treated with air abrasion only had the lowest value of shear bond and highest value ofmicroleakage The results of present study showed that specimens had a reduced shear bond in comparison withthe specimens of the same treatments after different thermocycling period

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