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Article
The effect of addition chlorhixidine gluconate (powder) on the properties of heat cured acrylic resin

Authors: Alia'a W. Alomari --- Nada Z. Mohammed --- Amer A Taqa
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2011 Volume: 11 Issue: SpIss Pages: S25-S34
Publisher: Mosul University جامعة الموصل

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Abstract

Aims of the Study: The current study aims to evaluate the effect of the addition of chlorohexidine gluconate (CHX) (powder) on some physical , mechanical properties and antimicrobial effect. Materials and Methods: In this study two hundred and forty samples of heat cured acrylic resin (Major base-2) were prepared and divided into: control group( without the addition of CHX) and experimental groups(with the addition of CHX(powder) at (1%, 2%, 3%)) to evaluate transverse strength, tensile strength, , surface hardness, dimensional accuracy, deflection , residual monomer in addition to antimicrobial effect for heat cured acrylic resin before and after the addition of CHX(powder). Results: Results showed a statistically significant difference at (p0.05) between control and experimental groups. The addition of CHX (powder) into heat cured acrylic resin increases its flexibility in addition to it's antimicrobial effect. Group of 1% CHX has the highest value of transverse strength, tensile strength ,surface hardness and dimensional accuracy after control group. Conclusions: In addition to its antimicrobial effect, CHX increases the flexibility of heat cured acrylic resin. As the concentration of added CHX increased, the flexibility of heat cured acrylic resin specimens will be increased

Keywords

CHX --- acrylic resin --- flexibility


Article
Effect of using two packing Technic on Hardness of two dental acrylic resin

Author: Najim O. Nasser
Journal: nursing national Iraqi specility المجلة العراقية الوطنية للعلوم التمريضية ISSN: 18122388 Year: 2012 Volume: 25 Issue: 1 Pages: 12-18
Publisher: Baghdad University جامعة بغداد

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Abstract

Objective: the aim of this study is to invest age and determine the effect of using (2) packing technique (conventional and new tension technique) on hardness of (2) types of heat cure acrylic resin which are (Ivoclar and Qual dental type). Methodology : this study was intended the using of two types of heat cure acrylic (IVoclar and Qual dental type) which are used in construction of complete denture which packed in two different packing technique (conventional and new tension technique) and accomplished by using a total of (40) specimens in diameter of ( 2mm thickness, 2 cm length and 1 cm width) . This specimens were sectioned and subdivide into (4) group each (10) specimens for one group , then signed as (A, Al B , B 1) according to the method of technique and type of acrylic that used . The hardness of the specimens were measured by shore hardness test in technology university, Baghdad. Results: this study revealed that the type of acrylic which packed by new tension technic had less effect by hardness in compared with conventional packing technic, the result also showed that the type of acrylic resin have a little effect on hardness of the two types, and also it show highly mean value of hardness was indicate in Qual dental type in conventional technique, while the least mean value of hardness showed in Ivoclar type in new tension technique. Recommendations : this study has been conducted as a preliminary for future studies to give a sit of about the effect of hardness on other types of commercial heat acrylic resin that used in construction of prosthodontics restoration and dented prosthesis, it necessary to evaluate the hardness of any material used in construction of denture bases , it is suggested to under take a farther studies about using advance technique and better apparatus and device in packing the acrylic material and measured the value of hardness and its effect on this material.

الهدف : تهدف الدراسة الى بيان مدى تأثير طريقتي تعليب ( الطريقة العادية للتعليب ثم طريقة الضغط الجديد ) على نوعين من مادةة الاكريلك الحار المستخدم في صناعة طقوم الأسنان وهما ( الإيفوكلار والكويل دينتل) على صلادة هذين النوعين من المادة . المنهجية : أجريت الدراسة باستخدام نوعين من مادة الاكريلك الحار المستخدم في تصنيع الطقوم نوع (الإيفوكلار) ثم نوع ( الكوايل دينتل) ثم تعليب هذين النوعين بطريقتين مختلفتين ، بالطريقة العادية لتعليب المادة أولاً ثم باستخدام جهاز الضغط الجديد ثانياً . تمت الدراسة باستخدام (40) عينة ونموذج بابعاد (2 ملم سمك ، 2 سم طول ، 1 سم عرض ) للعينة ، وزعت إلى اربع مجاميع بواقع (10) عينات لكل مجموعة ، وزعت المجاميع الاربعة وفق التأشيرات حسب طريقة التعليب المستخدمة ونوع الأركيلك المستخدم والطريقة المستخدمة .تم قياس الصلادة بمقياس شور للصلادة الجامعة التكنولوجية – بغداد . النتائج : اظهرت نتائج الدراسة التي خضعت للتحليل الإحصائي ان مادة الاكريلك المعلبة بنظام الضغط الجديد قليل التأثير على صلادة المادة في الطريقة العادية وأن لا تأثير على نوع الاكريلك المستخدم في الطريقتين كذلك بينت الدراسة ان اعلى قيمة لمتوسط الصلادة ظهرت في الطريقة العادية بينما اقل معدل للصلادة في الطريقة الاخرى كذلك تبين من الدراسة ان اعلى قيمة لمتوسط الصلادة ظهر في نوع ( الكوايل دينتل) في الطريقة العادية في حين معدل الصلادة لنوع (الإيفوكلار) كان بنسبة أقل . التوصيات : هذه الدراسة اعدت لتكون تمهيداً لسلسلة من الدراسات المستقبلية لبيان مدى تأثير الصلادة على أنواع اخرى من مادة الاكريلك التجاري المستخدم في صناعة الاسنان وإيجاد طرق أخرى مستحدثة لتعليب المادة باستخدام تقنيات حديثة. ونقترح تجهيز مختبرات صناعة الاسنان بأجهزة حديثة واستخدام التقنيات العالية في جميع مراحل وخطوات اعمال مادة الاكريلك المستخدمة في صناعة طقوم الاسنان وطرق قياس وتأثير خاصية الصلادة على هذه المادة .


Article
Porosity of different thickness of acrylic polymerized by different methods.

Author: Luay N Abood
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2007 Volume: 7 Issue: 10 Pages: 173-179
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: To evaluate the porosity that occur in the acrylic resin denture base polymerized by themicrowave cycle and conventional water bath with two different thickness, relation between thethickness of specimen and its percentage of porosity. Material and methods: Forty rectangular resinspecimens with the following dimensions (65×40×6mm), (65×40×3mm) were subdivided according topolymerization method into microwave cycle and conventional heat polymerization method to obtain10 specimens with different polymerization method and thickness, for each one of 4 groups. Porositywas calculated by measure the specimen volume before and after its immersion in water, data wereanalyzed by student t–test analysis at ( p< 0.05). Results: Showed that specimens of (6mm) that curedby microwave polymerization method showed significantly higher percentage of porosity whencompared to the same thickness of conventional water bath polymerized acrylic resin at (p<0.05), whileno significant difference between the percentage porosity of the conventional and microwave heatcured acrylic resin of (3mm) thickness specimens. Also there is no significant difference between thethickness of specimen and the conventional water bath method of heat cured acrylic resin. While formicrowave curing method of heat cured acrylic resin there is significant difference for increase ofpercentage of porosity with increase of thickness of specimens. Conclusions: The conventional acrylicresin of (≥3mm) specimens thickness can be polymerized with microwave curing method safely withless porosity , while for (≥ 6mm) specimens thickness is preferred to be polymerized by conventionalwater bath curing method


Article
Evaluation of Some Mechanical Properties of Reinforced Acrylic Resin Denture Base Material(An In Vitro Study)

Authors: Luma M Al–Nema --- Tarik Kassab Bashi
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2009 Volume: 9 Issue: 13 Pages: 57-65
Publisher: Mosul University جامعة الموصل

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Aims: To evaluate the effect of thickness of acrylic denture base resin on the transverse strength, also to evaluate the effect of metal and fiber reinforcements on the fracture resistance of denture base resinby four mechanical tests: Transverse strength; Charpy impact strength; Tensile strength and Rockwell Indentation Hardness. Materials and methods : Heat–cured resin, and three types of reinforcing metalswere used which were: The cobalt–chromium alloy mesh, stainless steel wire and nickel alloy plate.Three forms of glass fiber also were used: Random, woven, and aligned unidirectional. The effect of these reinforcing materials on the mechanical properties of heat–cured resin had been evaluated bymeasuring the transverse strength by the Instron testing machine, tensile strength by the Textile tensile strength Tester, the impact strength by the Charpy type impact Tester and finally the hardness by the Rockwell hardness tester. Three hundred samples were prepared in this study. Results: Revealed a statistically significant effect of thickness on the transverse strength of heat–cured resin. Results alsoshowed that all forms of fiber and metal reinforcements had a significant effect on the transverse strength, tensile strength , impact strength and hardness of denture base resin. Conclusions: The thickness significantly increased the transverse strength of denture base resin. All forms of metal and glass fiber reinforcement significantly improved the transverse strength, impact strength and tensile strength of denture base resin. All forms of metal and fiber reinforcement acted to reduce the hardness of denture base resin


Article
Evaluation of some physical properties of the copolymerized temporary crown and bridge auto–cured acrylic resin (Reinforcement)

Authors: Akram A Mohammad --- Nadiaa H Hasan --- Lamia T Rejab
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2007 Volume: 7 Issue: 10 Pages: 160-165
Publisher: Mosul University جامعة الموصل

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Aims: To evaluate some of the physical properties which are transverse strength, tensile strength,surface hardness, water sorption and solubility of the auto–cured acrylic resin when copolymerizedwith epoxy resin at two different ratios 10% and 20% of its weight and then compared with that ofauto–cured alone and heat–cured acrylic resin alone. materials and methods: The tested samples weredivided into four groups according to the materials to be used and the samples of each group weresubdivided according to the test to be done. The samples were prepared according to ADASpecification No. 12. Statistically analysis of the physical properties was with (ANOVA) and Duncan'smultiple range test to determine significant different at (p ≤ 0.05 ) level of significance, and the meanvalue of the water sorption and solubility ratios compared with accepted limit of ADA SpecificationNo. 12. Results: The transverse strength, tensile strength and surface hardness in this study showed thatthere was a highly significant difference between the four tested groups. The result appeared improvingof the mechanical properties and decreasing the ratio of water sorption and solubility of the auto–curedacrylic resin and the resin was reinforced when copolymerized at 10%, but the values still not reachedthat of the heat–cured acrylic resin and they became worse when copolymerized at 20%.


Article
The Effect of the Thermopress Curing Technique on the Water Sorption and Solubility of the Cold and Heat–Cured Acrylic Resins

Author: Lamia T Rejab
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2008 Volume: 8 Issue: 11 Pages: 11-17
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: This study aims to evaluate the effect of the thermopress curing technique on the water sorption
and solubility of the cold–cured and heat–cured acrylic resins and compared this technique with the
bench curing technique used for the cold–cured resin and with the conventional water bath curing technique
for the heat–cured resin. Materials and Methods: they were to measure the water sorption and
solubility, the specimens were prepared as disks with a dimension according to the ADA Specification
No. 12. So specimens were divided into five groups depending on the type of the resin ( cold and heat–
cured ) methods of curing which were ( thermopress, conventional water bath and bench cure ) and the
time of curing cycle. Specimens were weighed before and after immersion in the distilled water and
after drying with silica gel using an electronic balance to measure the water sorption and solubility.
One way analysis of variance (ANOVA) followed by Duncan , s multiple range test was performed to
determined the significant different between the mean values among the tested groups at (p< 0.05)
level of significance. Results: There is a significant differences between the water sorption and solubility
of resin that cured by the different curing methods and different curing cycle times. The water
sorption and solubility of resin specimens that cured by thermopress have the higher values. Conclusions:
The water sorption and solubility of the cold and heat–cured acrylic resins is affected by the curing
method. The curing under higher pressure produces specimens with lower water sorption and solubility
values.


Article
Effect of Different Dental Materials on the Surface Roughness of Acrylic Resin ( A comparative in vitro study )

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Abstract


Article
Antifungal Action of Some Natural Oils on Acrylic Resin Denture Base Materials

Author: Rana R AL- Sumaidae
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2012 Volume: 12 Issue: 20 Pages: 295-300
Publisher: Mosul University جامعة الموصل

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Aims: The study aims to evaluate the antifungal action of some natural oils (sun flower oil, sesame oil, nigella sativa, flax oil and ginger oil) in relation to nystatin suspension on acrylic resin denture base materials. Materials and method: The total number of specimens were seventy, they were (10×10×2mm). Half of the specimens were prepared from heat cured acrylic resin and the other half prepared from cold cured acrylic resin denture base materials, for each group they were immersed for 8hr in these oils after they had been infected with Candida albicans and incubated for 48hr. This study compared antifungal efficiency of sun flower oil, sesame oil, nigella sativa, flax oil and ginger oil. The statistical tests used were one way analysis of variance test, Dunnett t-test. Results: There were signifi-cant differences between all tested oils and distilled water in relation to antifungal action at (P=0.05). Conclusions: All the tested natural oils were effective antifungal agent.


Article
Evaluation of the effect of addition of polyester fiber on some mechanical properties of heat cure acrylic resin

Authors: Thikra M. Hachim ذكرى هاشم --- Zainab S. Abullah زينب عبد الله --- Yasamin T. Alausi ياسمين الالوسي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: special issue 1 Pages: 23-29
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This study aimed to evaluate the effect addition of polyester fibers on the some mechanical propertiesof heat cured acrylic resin (implant strength, flexural strength and hardness)Materials and methods: Ninety specimens were used in the study. Thirty specimens were used for impact strengthmeasurements (80mm X 10mm X 4mm) length, width and thickness respectively. The specimens divided into threetest groups (n=10), first group formed from heat cure acrylic resin without fiber reinforcement. Second group wasformed from heat cure acrylic resin was reinforced with 2 mm length polyester fiber and third group was formed fromheat cure acrylic resin reinforced with 4mm length polyester fiber, impact strength measured by impact testingdevice. 30 specimens with (65 mm X 10mm 2.5mm) length, width and thickness respectively were used in 3 groups(n=10) flexural strength test. The flexural strength was measured by using flexural testing device. 30 specimens with(65mm X 10m X 2.5mm) length width and thickness respectively were used for hardness test. The specimens weredivided into 3 group (n=10) as in impact strength and flexural strength.Hardness measured by using (shore D hardness tester TH210).Results: revealed statistically significant increase on impact strength especially on 4mm length when compared tocontrol group. Significant decreases in flexural strength of PMMP. When compared to control group with 4mm lengthfiber reinforcement. Non significant decrease when compared control group with 2mm length fiber reinforcedPMMA. Significant decrease in hardness of PMMA resin after reinforcement with 2mm, 4mm lengths polyester fibers.Conclusions: Strengthening with the polyester fiber decreased the flexural strength and hardness of the resin, butincreased impact strength. Thus when high impact acrylic resins are needed, fiber reinforced resins may be thematerial of choice

الھدف من ھذا البحث لتقییم تاثیر اضافة الیاف البولیستر للاكریلك الحراري على بعض الخواص المیكانیكیة للاكریلك الحراري (مقاومة الصدمة ,قوة الطي,صلادة السطح).استخدم في البحث 90 نموذج وقد قسمت الى 30 نموذج لكل خاصیة , 30 نموذج لقیاس قوة الصدمة بقیاسات ( 80 ملم* 10 ملم* 4ملم) الطول , العرض,السمك بالتتالي النماذج قسمتالى ثلاثة مجموعات (العدد= 10 ) للاختبار المجموعة الاولى شكلت من الاكریلك الحراري بدون اضافة الالیاف ,المجموعة الثانیة شكلت باضافة الالیاف بطول 2ملم,المجموعة الثالثةشكلت باضافة الالیاف بطول 4ملم. مقاومة الصدمة قیست بواسطة جھاز قیاس الصدمة .30 نموذج استخدمت لقیاس قوة الطي بقیاسات ( 65 ملم* 10 ملم* 2,5 ملم)الطول ,العرض,السمك بالتتالي ,قسمت الى ثلاثة مجامیع( العدد= 10 ) لكل مجموعة وتم قیاس قوة الطي بجھازقیاس قوة الطي. 30 نموذج استخدمت لقیاس صلادة السطح بنفس القیاسات المستخدمة لقیاس قوة الطي .عكست النتائج زیادة ملحوظة في مقاومة الصدمة وخاصة بعد اضافة الالیف بطول 4 ملم ونقصان ملحوظ في قوة الطي بعد اضافة الالیف بطول 4ملم مع نقصان غیر ملحوظ بعداضافة الالیاف بطول ال 2ملم. نقصان غیر ملحوظ لكلا الطولین على صلادة السطح. ھذه الدراسة استنتجت ان اضافة الیاف البولستر تقلل من قوة الطي والصلادة ولكن تزید من مقاومةالصدمة ولذلك عندما نرید ان نستخدم الاكریلك الحراري ذو المقاومة العالیة للصدمة نستخدم الاكریلك الحراري المدعم بالیاف البولیستر


Article
The effect of polypropylene fibers in different lengths on some properties of heat-cured acrylic resin processed by autoclave.

Author: Dr. Husam Mejbel Khalaf, B.D.S, M.Sc .* د. حسام مجبل
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2014 Volume: 11 Issue: 1 Pages: 57-66
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Background: some properties of heat-cured acrylic resin are required to beimproved (like flexural strength, hardness and porosity) by adding different types offibers like polypropylene fiber, also needed to determine these properties withaddition of polypropylene fibers and curing the polymer by autoclave. The aim of thisstudy was to evaluate the effect of adding polypropylene fibers in two differentlengths (6mm, 12mm) and concentration 2%, and the effect of autoclave processingon some properties(flexural, surface hardness and porosity).Material and method: A total No. of 120 specimens were prepared in this studyand divided into two main groups according to length of fibers (6mm,12mm) , eachmain group was subdivided into two groups according to method of adding the fiber(directly to the powder or immersed in monomer). Each group of them contain 10specimens for each test.Result: in this study, the transverse strength and surface hardness of heat curedacrylic reinforced by randomly oriented polypropylene fibers (12mm, 2%) regardlessto application method with higher significance than other groups. Fiber reinforcementand autoclave processing showed non-significant effect on porosity of heat cureacrylic resin according to ANOVA t-test.Conclusion: Reinforcement by randomly oriented polypropylene fiber (12mm,2%) added with and without immersion in monomer better than other groupsaccording to transverse strength and surface hardness with autoclave processing butthere is no effect of added fibers on porosity test.

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