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Article
The Influence of Saliva, Artificial Saliva and Propolis Extract on the Wettability of Heat−Cured and Visible Light−Cured Den-ture Base Material

Author: Luma M Al−Nema
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2011 Volume: 11 Issue: 1 Pages: 96-104
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: To evaluate and compare the effect of human saliva, artificial saliva and propolis extract on the wettability of heat−cured and visible light −cured denture base material .Materials and Methods: A total of 80 samples were prepared , 40 samples prepared from heat cured resin and the other 40 samples were prepared from light cured resin. These two groups were divided into four subgroups, control group, human saliva, artificial saliva and propolis. Contact angle measurements by sessile drop method with a micropipette using digital camera to determine the wettability of these samples. Mean values were compared statistically with one way analysis of variance (ANOVA),Duncan's multiple range test and t−test to determine the significant difference among the tested groups. Results: There is a signifi-cant differences of the mean values of the contact angle among the tested groups. The contact angle significantly decreased in all the treated samples. Conclusion: Heat cured resin has more wettability than light cured resin. Human saliva, artificial saliva and propolis increased the wettability of both heat cured and light cured resin


Article
Effect of Two Disinfectant Solutions on Wettability of Flexible Denture Base Material

Author: Asmaa A. Abdulkadir
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2015 Volume: 15 Issue: 2 Pages: 424-430
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: To evaluate wettability of flexible denture base martial after immersion in saliva, artificial saliva, chlorhexidine and sodium hypochlorite for 7 days period of time. Materials and methods: sixty rectangular shape sample of flexible denture base martial were prepared with one surface polished and another surface unpolished. These samples were stored in the previously mentioned four solutions in addition to the distilled water as a control group for 1 day and 7 days. Contact angle (parameter of wettability) were measured on both surfaces after each storage periods (1- day and 7 days). The statistical analysis to the data was performed using ANOVA and Duncan Multiple Range Test. Results: The results revealed that the wettability of unpolished flexible denture base material is significantly more than the polished surface. Sodium hypochlorite had significantly decrease the wettability of polished surfaces. Periods of storage had significant effect only on the wettability of polished surfaces rather than unpolished surfaces. Conclusions: Wettability of unpolished surface of flexible material is better than the wettability of the polished surface. The storage periods have no effect on the wettability of unpolished surface. Disinfectant solutions that have oxidizing effect (sodium hypochlorite) has a worsening effect on the wettability of flexible denture base materials.


Article
The Effect of Adding Nickel Element on Mechanical and Wear Properties of SiCp-Cu Composites
تأثیر أضافة النیكل على الخصائص المیكانیكیة والبلى للمتراكب ( SiCp-Cu)

Author: Samir B. Younis
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2010 Volume: 28 Issue: 21 Pages: 6228-6236
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Reinforced composites are prepared from a Copper as a matrix with SiCpowder in different percentage ( i.e 5-25 vol.%) .For each prepared reinforcedcomposite with respect to SiC addition , they divided into two parts , one undergo toaddition of Ni in fixed percentage (2 wt%) and the other part leave without addition.After drying , mixing and milling process, disc samples were prepared . thesesamples were heat treated at (900°C) using furnace at argon atmosphere. Density,porosity, Vicker microhardness , compressive strength were performed. Dry slidingwear tests of Cu–SiCp composites were carried out using pin on disc apparatus with atypical experimental plan of simultaneous variation of loads (5,10)N . The resultsshow that the density was decreased while porosity increased with SiC content , andthis was less remarkable with nickel presence. Vicker microhardness, compressstrength were improved by the nickel wettability on the reinforcement. Moreoverdecreasing in wear rate comparing with the absence one. The nickel presence modifiesthe interface structural model and is effective in passing load between the matrix andthe reinforcement, by lessening the extent of interfacial debonding.

تم تحضیر المتراكب المكون من النحاس كمادة أساس ودقائق من كاربید السلیكون كمادة تدعیم بنس ب م زج25 % وزناّ) , حبث حضرت مجموعتین من النسب أعلاه , الاولى تم أضافة عنصر النیكل الیھا بنسبة - مختلفة ( 5ثابنة ( 2% وزناّ) , والاخرى بقت كما ھي. وبع د عملی ة النجفی ف والخل ط ت م ك بس النس ب المحض رة غل ى ش كل900° ) وفي جو من الاركون . تم فحص الكثاف ة والمس امیة والص لادة ومقاوم ة C) أقراص تم تلبیدھا عند درجة5,10 ) . م ن النت ائج N) الانضغاط للعینات المحضرة, اضافة الى فحص البلى , حیث تم اس تخدام أحم ال مختلف ةالمستحصلة , تبین ان الكثافة تقل بازدیاد النسب الوزنیة لكاربید السلیكون تقابلھا زیادة ف ي نس بة المس امیة . لك نھذا العامل كان أقل تأثیراّ في العینات التي تحتویعلى عنصر النیكل . اضافة الى ذلك ان تلك الاض افة ف د حس نتمن الخصائص المیكانیكیة للمتراكب من صلادة ومقاومة انضغاط . علاوة على ذلك ص غر مع دل البل ى مقارن ةمع العینات التي یختفي فیھا عنصر النبكل , حیث ان وجوده یؤدي الى توزیع الحمل الموضوع بین مادة الاساسومادة التدعیم وبالتالي تفادي الانفصال الحادث في السطح البیني


Article
Studying Properties of Cu-Al-SiC Composites Prepared by P/M Technique
دراسة خصائص المتراكب (Cu-Al-SiC) الملبد متالورجيا المساحيق

Authors: Ziyad S. Ahmed --- Ali M. Mousa --- Samir B. Younis
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2012 Volume: 30 Issue: 7 Pages: 1240-1248
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

A composite of copper powder reinforced with SiCp (0-10 wt%) in whichaluminum powder of ( 2 wt%) was added for improving wettability of the ceramie phase. . The composite mixture was prepared by mixing with a ball mill for one hour to ensure a homogenous distribution on the composite .Gteen compacts pressed at (350MPa) a steel mold of (12mm)diameter were then sintered at (900 °C) for two hours in an electric furnace, in argon atmosphere . Optical microscopy, Density, porosity content and Vicker's hardness test were then conducted for the sintered samples. Obviously, it was concluded that there was enhancement of the physical and mechanical (hardness) properties of the sintered compacts with increasing the SiC content.

حضرت عينات متراكبة من مسحوق النحاس كمادة اساس ودقائق كاربيد السليكون بنسبة % %10 وزنا) كمواد تدعيم، اما مسحوق الالمنيوم فقد تمت اضافته الى المزيج بنسبة ثابتة 2 -0) وزنا وذلك لزيادة الترطيب السطحي. تم خلط المزيج بواسطة طاحونة كرات كهربائية دوارة لمدة (350MPa) ساعة للحصول على مسحوق متجانس. تم بعدها كبس العينات تحت ضغط يعادل 12 ، ثم لبدت في درجة حرارة mm بواسطة مكبس هيدروليكي في قالب فولاذي بقطر يساوي 9000 ) لمدة ساعتين في جو من غاز الاركون. ثم فحصالعينات المستحصلة باستخدام المجهر C) من خلال .( HVS- الضوئي وقياس الكثافة والمسامية والصلادة للعينات بواسطة جهاز( 1000النتائج المستحصلة ظهر بأن اضافة كاربيد السليكون الى النحاس قد عزز من خواصه الفيزيائية والمكيانيكية.


Article
Comparative study of wettability of different lining, tissue conditioning and denture base materials (in-vitro study)

Authors: Mostafa S. M. Al-Shaikhli مصطفى الشيخلي --- Amir H.M. Khamas عامر خماس
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: special issue 1 Pages: 24-30
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Wettability of denture base and denture relining materials is one of the most important properties fordenture retention, because it provides a condition in which saliva will spread over the surfaces with ease. Contactangle has been highlighted as the most important parameter concerning wettability of materials. This angle ischaracteristic of the substances due to the surface tension of the liquid and the surface energy of the solidMaterials and methods: One hundred and twenty specimens were prepared in six major groups (light cure acrylic,hot cure acrylic, flexible acrylic, soft liner, hard liner and tissue conditioner) with dimension of (25mm X 25mm X4mm)each group consists from 20 specimens. The wettability was measured using digital microscope and the retentionforce was measured using specially designed equipment.Results: The results obtained in the present study showed that there is a highly significant difference on the contactangle between different materials, different type of fluids (distilled water and synthetic saliva). The contact anglevalue of light cure acrylic is smaller than heat-cure acrylic, tissue conditioner, hard liner, flexible acrylic and soft linerrespectively; it was greater for synthetic saliva than those for distilled water,Conclusion: In conclusion, Light cure acrylic had the best wettability followed by hot cure acrylic and tissueconditioner respectively. There is an effect of the viscosity on the contact angle, and the contact angle has aneffect on the retention force. When the contact angle value was small the surface retention was higher than whenthese angles were large


Article
The effect of disinfection procedure and storage on wettability of hydrophilized condensation silicone impression materials

Author: Dr. Suha Fadhil Dulaimi / Assistant professor د. سها فاضل
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2016 Volume: 13 Issue: 1 Pages: 11-18
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Background: a newly developed hydrophilized condensation silicone impressionmaterial claimed to be hydrophilic, but exposure to disinfection procedure andstorage could alter the wettability of impression material. Thus, the aim ofpresent study was to evaluate the effect of impression disinfection by immersionin 0.5% NaOCl for 10 mints. on wettability of hydrophilized condensationsilicon . In addition, effect of storage after disinfection for two hours, measuredby contact angle of dental stone mix with impression surface.Materials and Methods: Hydrophilized condensation silicone (putty and wash type)tested with type III dental stone and 0.5% sodium hypochlorite disinfectantsolution were used in this study. Disinfection procedure by immersion for 10mint. Wettability was evaluated in simulation of regular clinical situation pouring2ml. of stone slurry on impression surface to form stone patty. Each pattysectioned into two halves, scanned with flat bed scanner and images printed.Dental stone mix contact angle with impression surface was measured withprotractor from scanned image of the cross section of stone patty. Measurementswere preformed before and after disinfection procedure, also after storage inhumid environment for two hours.Results: The putty type showed significant difference p<0.001 when subjected todisinfection and storage. The wash type showed no significant difference p>0.05when subjected to disinfection or storage. Both types together they were notaffected by disinfection procedure p>0.05, but storage had significant effectp<0.001 on wettability.Conclusions: For the hydrophilized condensation silicone using both types together(putty + wash) for making impression improve wettability even afterdisinfection. Delay pouring impression for two hours cause deterioration ofimpression wettability.


Article
Wettability of Al2O3 by Aluminum and Al-Mg Alloys
التبللية للالومينا من قبل منصهر الالمنيوم وسبيكة Al-Mg

Authors: M. S. Waheed --- Ali I. Salih
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2010 Volume: 28 Issue: 9 Pages: 1771-1777
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The wettablity at a liquid of pure-Al or Al-Mg alloys/ Al2O3 interface wasevaluated by the sessile drop method at 700oC and with a vacuum pressure of10-4Pa. The value of contact angle varies (decreases) with time of contact withAl2O3 substrate. The reduction in θ of the Al-Mg alloy was proportional to thereduction in surface tension γlv of Al, and to reactions that took place at the Alalloy/Al2O3 interface.

تم قياس التبللية بين منصهر الالمنيوم وسبيكه الالمنيوم- مغنيسيوم مع سطح الالومين ا700 وضغط oC بطريقة القطرة السائلة الموضوعة على سطح أملس ومستوي عند درجة حرارة10-4 . قيمة زاوية الترطيب تتغير (تنخفض) مع زمن التماس بين قطرة المعدن Pa تفريغالمنصهر وسطح الالومينا, وكذلك تنخفض مع أنخفاض قيمة الشد السطحي للمعدن المنصهر, وتنخفض مع حدوث التفاعل عند السطح البيني الفاصل.


Article
Microstructural Study of Copper-Carbon Composite Interface

Author: A.A.R. Abdullah
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2010 Volume: 6 Issue: 2 Pages: 25-29
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

Graphite is a very attractive candidate for copper-metal matrix composites. However, copper does not wet graphite, which makes the production of copper-graphite composites difficult. Because of the strong possibilities of these combinations in forming highly desirable composites, copper-carbon composites prepared by hot uniaxial pressure were investigated. The copper-carbon interface is of the samples was examined microscopically using optical microscopy. The observed microstructure at copper interface is composed of copper-carbon interaction layer. The adhesion between copper and graphite was achieved. However, there is no intimate contact between copper and graphite film at interface. To determine the diffusion of carbon through copper matrix by X-ray diffraction was used.


Article
The effect of plasma treatment on the bonding of soft denture liners to heat cured acrylic resin denture base material and on some surface properties of acrylic resin polymer

Authors: Shaymaa H. Masood شيماء مسعود --- Salah A. Mohamed صلاح محمد
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: 3 Pages: 29-35
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Acrylic resin polymers used in dentistry, are usually with problems in bonding, especially failure of thebond with soft denture lining materials. The aim of this study is to investigate the effect of plasma treatment on tensilebond strength, wettability and on physical surface changes for acrylic resin polymer.Materials and methods: Heat cured acrylic resin specimens with dimensions 8×10×30 mm were prepared for tensilebond strength test, in which each two acrylic specimens were joined by a 3-mm thick soft liner (Vertex Soft,Molloplast-B). Another heat curd acrylic resin specimens were prepared with dimensions 2×8×30 mm for wettabilitytest and physical surface analysis. For each test done in this study, the specimens were grouped as control, oxygenplasma treated and argon plasma treated acrylic specimens.Results: Plasma treatment increased the tensile bond strength for both Vertex and Molloplast-B soft lining materials,also induced a decrease in water contact angle values (i.e., increase in wettability) for oxygen and argon plasmatreated groups compared with control group, with highly significant difference (P <0.01) among groups. AFM imagesshowed a collection of new distinct nanograins and numerous grooves (pitlike-structures) after oxygen and argonplasma treatment with argon plasma treatment showed more new nanograins, deepest grooves and highestprotuberances which increased the surface-roughness (i.e. nano-roughness) when compared with control andoxygen plasma treated groups.Conclusion: Plasma treatment was an effective method for increasing tensile bond strength, wettebility, and inducedphysical topographical surface changes that increased the surface roughness(mainly after argon plasmatreatment) for plasma treated heat cured acrylic resin specimens


Article
Effect of poly propylene fibers incorporation and their oxygen plasma treatment on tensile strength, wettability and wear resistance of heat cure denture base acrylic resin

Author: Hasanain K.A. Alalwan
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 4 Pages: 32-38
Publisher: Baghdad University جامعة بغداد

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Abstract

Background:Recently, Poly propylene fibers with and without plasma treatment have been used to reinforce heatcure denture base acrylic but, so far some of properties like tensile strength , wettability and wear resistance notevaluated yet, the aim of the study is to clarify the influence of incorporation of treated and untreated fibers on theseproperties.Materials and methods: Twenty one specimens were fabricated for every tested property(tensile strength, wearresistance and wettability) that classified into three groups(control, untreated poly propylene fibers reinforcedspecimens and Oxygen plasma treated group)and for each test seven samples were used(n=7). Tensile strength wastested using Instron universal testing machine, wear resistance was evaluated by pin on disk wear measurementmethod while, a digital microscope supplied with high resolution camera was utilized to measure the contact anglereflecting wettability grade. One wayANOVA table and LSD were used to analyze the results.Results: The tensile strength showed a paradoxical effect, plasma treated samples group demonstrated a negativeinfluence in contrary, to the untreated group that revealed positive high significant impression. The plasma treatedgroup had manifested a- positive significant difference regarding wear resistance whilst, the beneficial effect oftreated and untreated Poly propylene fibers addition was obvious with high significant difference.Conclusion: Incorporation of O2 plasma treated and untreated poly propylene fibers to heat cure poly methylmethacrylate resin was beneficial regarding the tested properties except for addition of plasma treated Polypropylene fibers on tensile strength

الخلفیة:حدیثا الیاف البولي بروبیلین مع و بدون معالجة بلازما الاوكسجین قد استخدمت في تقویة الراتنج الاكریلي الحراري لقاعدة الطقم لكن لحد الان لم یختبر تاثیرھا على قوة الشد وقابلیةالترطب ومقاومة البلى.المواد و الاسالیب:احدى و عشرین عینة قد اختبرت لكل صفة من الصفات الثلاثة بواقع سبعة نماذج اختباریةلكل من مجموعة السیطرةو مجموعة النماذج المدعمة بالالیاف المعالجة ببلازماالاؤكسجین والمجموعة الاخیرة للالیاف غیر امعالجة.اختبرت قوة الشد بجھاز الانسترون و اختبرت قابلیة الترطب بمایكروسكوب رقمي وفحصت مقومة البلى بطریقة المسمار علىالقرص.النتائج:اظھرت النتائج تباینا واضحا عند فحصقوة الشد لصالح اضافة الالیاف غیر المعالجة بینما بینت تاثیر سلبي للالیاف المعالجة اما ما یخصالصفتین الأخرتین فقد اظھرتا تأثراایجابیا خصوصا في صفة قابلیة الترطیب.الاستنتاج:مع محدودیة البحث یستنتج بأن اضافة الالیاف المعالجة و غیر المعالجة اثر ایجابیا بالصفات المدروسة في ما عدا قوة الشد مع الالیاف المعالجة

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