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Article
Measurement of water sorption of five different composite resin materials

Author: Waleed M. Khalil وليد خليل
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2005 Volume: 17 Issue: 3 Pages: 37-41
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Water sorption may affect composite resin materials by reducing their mechanical properties and wear resistance .The aim of this study is to measure the water sorption of five different composite resin materials, for different time intervals.Materials and methods: A stainless steel mold of 4 mm width, 8 mm length and 4 mm depth was constructed to form composite blocks. Seven blocks were made of each test resin composite material. All specimens were placed in a silica-gel desiccator for 48 hours. The samples were then weighed thrice using calibrated electronic microbalance, the average reading was recorded to the nearest 0.0001g. The specimens were kept in individual containers in deionized distilled water at 37 ºC.All specimens were periodically weighed. The weight measurements were taken at 2, 8, 14, 28,42,56,70,100,150 and 240 days intervals.Results: The statistical analysis of the results showed that all composite resin specimens continued to gain weight for a period of 28 days. After that period, the weight gain continued, although at a reduced rate. The changes after the 28 days period were small for the Herculite XRV, Tetric ceram and Tetric composite resins, and greater for the Filtek P60 and Composan LCM composite resins.Conclusion: In this study water absorption increased steadily for all materials. The percentage weight change showed a tendency to increase with the time of water storage. This study concludes that over a period of 8 months, the differences in water sorption capacity of the five composite resin materials are related to the differences in the amount of filler loading in the composite resin matrix. With one exception, the composite resin materials with the largest quantity of fillers had the least water sorption capacity after eight months of storage in water


Article
Water sorption of three types of composite resins

Authors: Dr. Samar Abdul Hamed Yasin. B.D.S, M.Sc د. سمر عبد الحميد --- Dr. Linz Ali Shalan. B.D.S, M.Sc.. د. لنز علي
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2011 Volume: 8 Issue: 3 Pages: 242-247
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Silorane low shrink composite resin material introduced with a non-methacrylateresin matrix to realize a fundamental improvement in cure shrinkage, clinical andphysical properties. The aim of this study is to measure the water sorption of threetype of composite material: Filtek P90, Filtek P60, IPS Empress composites afterimmersion in deionized distilled water as a function of time.Thirty disk shape plastic molds (4 mm diameter and 2mm thickness) wereconstructed to form composite blocks. Teen blocks were made from Filtek P 90(Silorane) GI, Filtek P 60 (packable) GII and IPS Empress (Nanohybrid) GIII. Allspecimens were placed in a silica-gel desiccator for 48 hours. The samples were thenweighed three times using calibrated electronic microbalance and the average readingwas recorded to the nearest 0. 0001g then specimens were kept in individualcontainers in deionized distilled water at 37 oC. All specimens were periodicallyweighed. The weight measurements were taken from the second day after incubationand continue as one measurement every week for 6 weeks. Data were subjected tostatistical analysis using descriptive analysis, ANOVA and least significantdifferences LSD test.Statistical analysis of the results showed that all the specimens continued to gainweight for a period of 4 weeks. After that period the weight gain continued, althoughat reduced rate. Filtek P90 (Silorane) GI has highly significant less water sorptionvalue ( p < 0.01) than the other groups after 6 weeks, while there was no significantdifferences ( p > 0.٠٥) between IPS Empress (Nanohybrid ) GIII and Filtek P60 (Packable ) GII in their water sorption value with higher value for GIII.Silorane which based on siloxane and oxirane resin matrix has less value after 6weeks followed by Packable composite while IPS Empress has higher value for watersorption. This study concluded that the differences in water sorption capacity of thethree composite resin materials are related to the differences in the type of resinmatrix, the amount of filler loading and filler particle size.


Article
Water sorption of light–cured composites

Author: Ammar Kh Al–Nori
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2005 Volume: 5 Issue: 5 Pages: 1-5
Publisher: Mosul University جامعة الموصل

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Abstract

The aim of the present research was to study the percentagewater sorption and solubility of Esthet compositeresin based on an ethoxylated bisphenol A glycol dimethacrylate(Bis–EMA) and Heliomolar composite resin basedon bisphenol A glycol dimethacrylate (Bis–GMA). Six specimenswere prepared for each material using aluminum disc 15mm in diameter and 1 mm in thickness between two glassslides; then they were light cured for 80 seconds on each side.Percentage water sorption and solubility were measured afterone week and one month. The results showed that water sorptionafter 1 week for Esthet composite and Heliomolar compositewere 0.433 and 1.12, respectively and solubility were0.074 and 1.066, respectively; while water sorption after 1month were 0.517 and 2.57, respectively and solubility were0.176 and 2.689, respectively.It could be concluded that the percentage sorption andsolubility of composite based on Bis–EMA were significantlylower than that based on Bis–GMA.


Article
An evaluation of water absorption of Giomer in comparison to other resin-based restorative materials

Authors: Shatha Abdul Kareem شذى عبد الكريم --- Rasha H. Jehad رشا جهاد
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: 3 Pages: 25-28
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Polymeric composites have been widely used as dental restorative materials. A fundamentalknowledge and understanding of the behavior of these materials in the oral cavity is essential to improve theirproperties and performance. The goal of this study was to measure water sorption of four composite resinscontaining different filler and resin matrix contents.Materials and method: Resin composite specimens giomer (Beautifil II) Filtek™ P90, Filtek™ Z350 XT, and Tetric NCeramwere prepared in a cylindrical mould of 3mm thickness and 6mm diameter (n=10) and light cured . Allspecimens placed in silica-gel desiccators at 37˚C for seven days, a constant weight was obtained. All samples wereimmersed in deionized distilled water at 37˚C and weighed at suitable time interval once a week for 30 days. Watersorption was calculated based on ISO 4049. Data were subjected to student t- test.Results: Silorane and Giomer composites showed the lowest values of water sorption, while Z350 and Tetric N-Ceramdisplayed the highest values at a period of 4 weeks.Conclusion: Each resin- matrix composite varied in water sorption which may affect clinical service. The attainedwater sorption values are mainly influenced by the generic type of material and variations occurring betweenmaterials of the same type may result from differences in resin matrix compositions


Article
The effect of adding micro zinc oxide filler to heat-polymerizing acrylic resin on some physical properties

Journal: Muthanna Medical Journal مجلة المثنى الطبية ISSN: 2226146x Year: 2016 Volume: 3 Issue: 2 Pages: 80-85
Publisher: Al-Muthanna University جامعة المثنى

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Abstract

Statement of problem: In dentistry, the acrylic resins are the common materials used for fabrication of removable dentures to restore function, appearance, etc. However, such restorative substances have to be lacking some physical properties. The aim of the current study to assess the effect of zinc oxide filler on some physical properties of heat cured acrylic resin. A total of 40 acrylic specimens were fabricated. Depending on the type of test, they were divided into water sorption and porosity groups. For each group, 20 specimens were reinforced with zinc oxide particles at 1% by weight and the others were considered as control. The porosity and water sorption tests were carried out for each specimen. The specimen’s data were analyzed and comparison was made by independent t test. The results showed that there was a slightly reduction in water sorption and porosity after incorporation of zinc oxide filler. In conclusion; the addition of ZnO powder to heat cured acrylic resins affects slightly their physical properties.

Keywords

Zinc oxide --- Acrylic --- Porosity --- Water sorption


Article
Water sorption of heat–cured acrylic resin

Authors: Lamia T Rejab --- Ahmed MA Hussain --- Ammar Kh Al-Nori
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2007 Volume: 7 Issue: 10 Pages: 186-194
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: To evaluate the effect of the different curing methods conventional water bath heat–curing andmicrowave energy curing method and different immersion periods on the water sorption and solubilityof the different types of heat–cured acrylic resins. Materials and methods: Water sorption and solubilitywere measured by means of mass change in the materials after water saturation and dehydration. Twodifferent commercial heat–cured acrylic resins Major Base 2, and Quayle Dental resins were used in thisstudy. Specimens were divided into two groups depending on the curing method. Thirty two specimenswere prepared, eight specimens for each material in each group. Specimens were immersed in distilledwater, and then subsequently removed from their containers at 1 week and 1 month of immersion forevaluation. Mean values wear compared statistically with one way analysis of variance followed byDuncan's multiple range test to determined the significant different among the groups at (p< 0.05) levelof significance. Results: showed that the curing method and immersion period have a significant effecton the water sorption and solubility ratios of the resins. Curing by microwave energy method andincreasing immersion period caused increasing in the ratios. The type of heat–cured acrylic resin has aneffect but the difference was not significant. Conclusion: the curing method, immersion period and typesof the acrylic resin have an effect on the absorption and solubility ratios.


Article
Effect of Conventional Polishing Procedure in Water Sorption of Cold and Heat Cured Acrylic Denture Base Material

Author: Azad Mohammed Ridha Al-Muthaffer
Journal: Medical Journal of Babylon مجلة بابل الطبية ISSN: 1812156X 23126760 Year: 2016 Volume: 13 Issue: 2 Pages: 481 -488
Publisher: Babylon University جامعة بابل

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Abstract

Acrylic resin is almost universally for partial or complete denture base construction due to its favorable properties. Unfortunately some disadvantages such as water sorption have been reported which causes dimensional changes that may subject the acrylic denture base to internal stresses, so the water sorption is a physical property of importance. Forty square shaped specimens (twenty specimens for heat and cold cured acrylic material) were prepared. Ten specimens from heat cured acrylic (HP) and cold cured acrylic (CP) material were polished, and ten specimens from heat cured acrylic (Hx) and cold cured acrylic (Cx) were not polished as control group. At room temperature, all specimens were weighed; this weight value was considered the initial weight of the specimen (W0). All specimens were kept in distilled water bath for 24 hours, and then specimens were weighed(W1)then the specimens were kept out of water bath for 24 hours to dry to (W0), and all samples return back to water bath for 24 hours to weigh again (W2). This manner was repeated till (W4).There is a significant difference (p=0.018) between (CP) and (Cx) and a significant difference (p=0.047) between (HP) and (Hx) and no significant difference between cold and heat cured acrylic before (p=0.699) and after polishing (p=0.52) at (p ≤0.05).


Article
The effect of denture cleansers on the color stability, water sorption and water solubility of stained light cured acrylic denture base material

Author: Dr. Aseel Mohammed Al-Hachem Al-Khafaji, B.D.S., M.Sc.* د.اسيل محمد
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2007 Volume: 4 Issue: 2 Pages: 174-181
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The dirty denture may have undesirable effect on patient's health and ability to successful wear of the denture, if a patient's denture becomes unsanitary, the consequences may be bad breath, poor esthetic, denture stomatitis and angular cheilitis and the using of the denture cleanser is the solution for this problem but the prolong use of such cleansers may affect the properties of the denture. The aim of the study is to observe the effect of denture cleansers on color stability, water sorption and water solubility of the light cured acrylic resin after their immersion in tea solution.Light curing acrylic resin was prepared and immersed in four types of denture cleansers after there staining with tea then color stability, water sorption and water solubility of acrylic resin was measured.There were no changes in the stained acrylic properties when the samples were immersed in prepared denture cleansers and in the alkaline peroxide cleanser compared to that immersed in the distilled water in respect to color stability, sorption and solubility of the testing groups.The water sorption, water solubility and color stability of the light cured acrylic resin where immersed in the prepared denture cleanser solutions are in accordance with the American dental association no.12. The denture cleanser are good and satisfactory cleanser materials for the acrylic resin denture base and it’s recommended for cleansing the prostheses which are cured by light curing method.


Article
The Effect of Different Types of Separating Medium On Some Physical Properties of Processing Acrylic Denture-base with Two Investment Materials: A comparative Study

Author: Nihad H. Mohammed
Journal: nursing national Iraqi specility المجلة العراقية الوطنية للعلوم التمريضية ISSN: 18122388 Year: 2011 Volume: 24 Issue: 2 Pages: 94-109
Publisher: Baghdad University جامعة بغداد

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Abstract

Objective(s): In the present study, glycerin is used as a substitute for tin-foil and cold mold seal (Alginate mould seal) in the process of curing heat and cold-cure acrylic resin denture base against stone and plaster.Methodology: 60 specimens were prepared from heat-cure acrylic resin and cold-cure acrylic resin denture base. The study includes 12 groups of specimens depending on the type of processing, investment material and type of separating medium that are used in curing process. Each group of them contains 5 specimens for each test. Some of physical properties of the processed acrylic denture base that (water sorption and solubility) have been compared with those processed using tin-foil and tin-foil substitute.Results: The results have shown that tin-foil is still the best separating medium that is used due to the best properties obtained when using tin-foil as a separating medium, while no significant differences have been observed between glycerin and cold mold seal specimens in respect to water sorption and solubility of the testing groups.Recommendations: that glycerin can be considered as a satisfactory separating medium for both heat and cold-cured acrylic denture base resins, especially because it is easy to get, easy to use and cheap.

الهدف: لبيان تأثير تبلمر الراتنج الاكريلي يجب فصل سطح القالب عن سطح الجبس لمنع سائل الراتنجي الاكريلي من اختراق الجبس من ناحية ودخول الماء الموجود في الجبس من التسرب إلى الراتنج الاكريلي من ناحية أخرى وكذلك للتقليل من الخشونة الموجودة على أسطح قوالب الجبس التي يمكن أن تخترق وتلتصق إلى قاعدة الطقم الاكرليكي وبالتالي توثر سلباً على قوة الطقم الاكريلي وتسبب له الكثير من الخدش والتكسر. ولتفادي ولمنع مثل هذا الالتصاق، يجب استعمال مادة عازلة جيدة والمعتاد هو استعمال رقائق القصدير المعدنية التي تعدّ من أحسن أنواع المواد العازلة في مجال صناعة الأسنان ولكن لصعوبة استعمالها، تمّ استعمال البديل وهو الجليسيرين وكبديل صوديوم ختم القالب وتمّ إجراء مقارنة بين هده الأنواع في هده الدراسة.المنهجيـة: أخذت (60) عيّنة موزعة على مجموعتين رئيستين حسب عملية الطبخ (المعالجة) الراتنج الاكريلي المعالج ذاتياً وحرارياً مع مادة الجبس. قسمت بالتالي إلى (5) عينات بالإعتماد على نوع المواد العازلة المستعملة ونوع مادة الجبس وتمّ قياس الصفات الفيزيائية وهي قابلية الامتصاص وقابلية الذوبان.النتائـج: أظهرت النتائج أنّ رقائق القصدير أثبتت فعاليتها العالية وأنها الأفضل كمادة عازلة. بينما الجليسيرين وبديل صوديوم ختم القالب لم يكن بينهما أي فروقات إحصائية معنوية ملحوظة بقياس قابلية الذوبان والامتصاص.التوصيات : أولاً تعدّ مادة رقائق القصدير هي الأفضل كمادة عازلة فيما يتعلق بقابلية الامتصاص والذوبان لمادة الراتنج الاكريلكي وثانياً إمكانية استعمال الجليسيرين كمادة عازلة تعطي نتائج جيدة ومقنعة وذلك لسهولة الحصول عليها وتوفرها.

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