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Article
The influence of flowable composite liner on microleakage of class II packable composite resin restoration with different application techniques (Comparative study)

Authors: Jalal B. Al-Kalamchi جلال الكلامجي --- 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: 19-24
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This in vitro study was conducted to evaluate and compare the influence of flowable composite anddifferent application techniques of class II packable composite restoration on dentinal leakage.Materials and methods: Thirty human freshly-extracted Maxillary premolars were selected for this study. ConventionalClass II MOD cavities were prepared in the sample teeth which were then divided into five groups .Each groupconsist of ten boxes either MO or DO according to the restorative procedure used except group A which consist oftwenty boxes(ten teeth with MOD amalgam restoration). Group A: ten teeth where restored by amalgam- (SDIAustralia) high strength admix amalgam type.Group B: ten teeth in which the mesio-occlusal (MO) sides wererestored by {adhesive + flowable composite + one bulk packable composite (Filtek P60)}. Group C: ten teeth inwhich the disto-occlusal (DO) sides were restored by {adhesive +one bulk packable composite, (Filtek P60)}.Group D:ten teeth in which the mesio-occlusal (MO) sides were restored by {adhesive + flowable composite + successivebuild up technique for packable composite, (Filtek P60)}. Group E: ten teeth in which the disto-occlusal (DO) sideswere restored by {adhesive+ successive build up technique for packable composite, (Filtek P60)}. Afterthermocycling and immersion in 2% methylene blue, the teeth were sectioned longitudinally mesio-occluso-distaland dye penetration was evaluated using a stereomicrscope, microleakage was recorded in mm.Results and Conclusions: ANOVA test and least significant difference (LSD) test were used to analyze the results, andthe results showed that the use of flowable composite resin as a liner with packable composite resin decreases theamount of dentinal microleakage, and the restorative technique of packable composite whether it is bulk build uptechnique, or incremental successive build up technique has no difference on the improvement of microleakgevalue, and the packable resin composite restoration whatever applied with different application techniques orrestored with or without flowable composite it still had or scored higher microleakage than amalgam restoration


Article
An Evaluation of Mechanical Properties of Different Types of Composite Resins (An in Vitro Study)

Author: Shaymaa SH. Hassan
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2014 Volume: 14 Issue: 1 Pages: 123-131
Publisher: Mosul University جامعة الموصل

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Abstract

The aim of this study was to evaluate the mechanical properties (compressive strength (CS), diametral tensile strength (DTS), flexural strength (FS) and modulus of elasticity (ME)) of different types of composite resins. Materials and Methods: Two flowable composites (tgflow, Tetric N-Flow) and two conventional composites (tgmicrohybrid, Tetric N-Ceram), were used in this study. For CS measurement, eight specimens of each material (3mm diameter x 6mm height) were prepared. For DTS measurement, eight specimens of each material (6mm diamerter x 3mm height) were prepared. For FS measurement, of each material eight bar shaped (2mm x 2mm x 25mm) specimens were prepared. The FS and ME were determined by three point bending method. The specimens were stored in distilled water at 37˚C for 7 days, then tested on a universal testing machine at a crosshead speed of 1mm/mint. Independent sample t-test and Duncan test were used for statistical analysis. Results: The CS, DTS and ME of flowable composites were significantly lower than that of the conventional composites, the FS of flowable (Tetric N-Flow) composite was significantly lower than that of the conventional (Tetric N-Ceram) composites but there was no significant difference between tgmicrohybrid composite and tgflow composite in FS. Conclusions: It can be concluded that the mechanical properties of two flowa-ble types composites were inferior than that of the two conventional types composites


Article
Tensile force measurement by using different lingual retainer wires, bonding materials types and thickness (A comparative in vitro study)

Authors: Yassameen A. Salih ياسين صالح --- Mushriq F. Al-Janabi مشرق فوزي الجنابي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 2 Pages: 167-172
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The bonded orthodontic retainer constructed from multistrand wire and composite is an efficientesthetic retainer, which can be maintained long-term. Clinical failures of bonded orthodontic retainers, mostcommonly at the wire/composite interface, have been reported. This in vitro investigation aimed to evaluate thetensile forces of selected multistrand wires and composite materials that are available for use in the construction ofbonded fixed retainers.Materials and Methods: The study sample includes 120 wires with three types of retainer wires (3 braided strandsOrthotechnology, 8 braided strands G&H Orthodontics, 6 coaxial strands Orthoclassic wires), two types of adhesive(flowable Orthotechnology, non flowable G&H Orthodontics composites) and two thickness of the adhesive(1mm, 2mm). The samples were prepared for each composite in which a wire was embedded; then the compositewas light cured for 40 seconds and the specimens were stored in artificial saliva at 37°C in the incubator for 24 hours.The ends of the wire were drawn up and tensile force was applied through Tinius-Olsen universal testing machine untilthe resin failed and the results were recorded in Newton (N).Results: Statistical analysis showed that there was a highly significant difference (P ≤ 0.01) among the mean values oftensile forces of the three types of retainer wires in each thickness of composite with exception of a non significantdifference (P > 0.05) between (3 braided) and (8 braided) and a non significant difference (P > 0.05) between (3braided) and (6 coaxial) in both thickness of composite, a highly significant difference (P ≤ 0.01) between the twothickness of both composite types in each wire type and a highly significant difference (P ≤ 0.01) between the twotypes of composite in each wire type of both thickness of composite.Conclusion: The result of this study revealed that the 8 braided strands retainer wire shows the highest values oftensile force among the tested retainer wires, the non flowable composite demonstrates a higher tensile force thanthe flowable composite and increasing the thickness of composite overlying the wire increased the force required todetach the wire from the composite


Article
Effects of Flowable Composite Resin and curing method on Microleakage

Author: Neam N Al-Yousifany
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2010 Volume: 10 Issue: 1 Pages: 1-7
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: The purpose of this invitro study was to evaluate the effects of a flowable composite associated with an adhesive, either light cured separately or co-cured on the microleakage of class V composite restorations. Material and methods: Sixty extracted human premolars were prepared with standar-dized box shaped class V cavities of 3.0mm (Mesial distal), 2.mm (occlusal gingival) and 2.0mm depth with margins located on enamel and dentin on the buccal surfaces. The cavities were randomly as-signed in the three groups (n=20): Group 1- single bond + tetric ceram (hybrid composite) as control group. Group 2- single bond + tetric flow (flowable composite) light cured simultaneously + tetric ceram. Group 3- single bond + tetric flow light cured separately + tetric ceram. After sto-rage period of one week in water, All specimens were thermo-cycled for 300 times with 15 seconds dwell time, and immersed in 2% methylene blue, sectioned and evaluated for microleakage using 0-3 scale. Data were subjected to Fisher Freeman Halton test at p<0.05. Results: Statistical significant dif-ferences between the three tested groups was observed. Group 3 (Flowable and adhesive cured sepa-rately) revealed the less microleakage. Conclusions: The marginal seal of Cl V cavities could im-proved by the use of flowable resin with rigid composite resin, but even with supposedly better flow and adaptation characteristic of this material it could not completely sealed the tooth/ restoration inter-face especially at the cervical margins.


Article
Microleakage evaluation of two types of pit and fissure sealants using two different methods, (in vitro study)

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Abstract

Background: Clinical preventive procedures must be done after careful assessment;one of the major risk factor is the occlusal morphology of the posterior teeth. Thesecaries free fissures must be sealed. This in vitro study evaluated the microleakage oftwo types of sealant materials (unfilled resin and flowable composite) on enamelsurfaces prepared using two methods (acid etching with enameloplasty and acidetching alone).Material and methods: Thirty two extracted human third molar were selected andrandomly assigned in to 4 groups of eight teeth each; group A, the occlusal surfaces ofteeth were acid etched ,then sealed with concise white sealant; group B, they wereacid etched then sealed with wave mv flowable composite ;group C, they wereprepared with bur ,acid etched ,then sealed with concise white sealant ;group D, theywere prepared by bur, acid etched, then sealed with wave mv flowable composite. Thesealed surfaces were stored for seven days in distilled water, then specimens werethermocycled 500 cycles, immersed 24 hours in a 2% buffered methylene blue dye,then sectioned and analyzed for leakage under a stereo microscope. Chi-square testwas performed to test the differences of leakage among the four groups.Results: The results showed that there was no significant difference (p>0.05) inmicroleakage for the same material with and without bur preparation. Concise whitesealant produced significantly (p<0.05) less microlaekage than wave flowablecomposite.Conclusion: under the conditions of the present study, bur preparation(enameloplasty) followed by acid etching produces no less microlaekage than did acidetching alone. Concise white sealant (unfilled resin) demonstrated less amount ofmicrolaekage when compared to wave mv flowable composite.

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