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Article
The effect of various staining agents on color stability of acrylic denture teeth materials. (In vitro study)

Authors: Farhan Dakhil Salman --- Raya Mohammed Jawad Al- Gaban
Journal: journal of kerbala university مجلة جامعة كربلاء ISSN: 18130410 Year: 2011 Volume: 9 Issue: 1 Pages: 199-210
Publisher: Kerbala University جامعة كربلاء

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Abstract

The aims of this study was to evaluated of effect the color stability of acrylic denture teeth when exposed to common beverages (coffee, tea and cola) with evaluate of change in the different time after [24 hour, 1 week, 2 weeks and 1 month] to obtain on high aesthetic of acrylic denture teeth.The color stability of acrylic denture teeth is very important factor influencing consumer's acceptability of the aesthetic. The stain solution is effecting the teeth when immersing for long time that replacement of natural color of acrylic teeth, additives has contributed in increasing the color change which result unacceptable of prosthodontic the acrylic denture teeth. In present study (128) samples were immersed into three staining drinks (coffee, tea and cola) as test groups and distilled water as a control group. Color stability measurements of teeth were performed by using a spectrophotometer device. The Color change values were determined after [24 hours, 1 week, 2 weeks and 1 month] of immersion.The Result of the Color stability variable analysis differences were used ANOVA and LSD. The color stability of all denture teeth was a high significant difference (p< 0.01) affected by the immersion of stain solution period. Cola was found to be the most the color change of the denture teeth because that the composition of the cola is the phosphoric acid which lead to scratch of the enemal surface of the denture teeth, also pure agent- materials among the solutions tested (p<0.01). It was concluded that acrylic denture teeth exposed to higher degree of color change and that depended on the amount of color change in each group that increased proportionally with time.

الهدف من هذه الدراسة تقييم تاثير ثباتية اللون للاسنان الاكريكلية عند غمرها بالسوائل التالية وهي( القهوة، الشاي والكولا)مع تقييم التغير في الاوقات المختلفة وهي( 24 ساعة، اسبوع واحد، اسبوعين والشهر واحد) للحصول على اعلى جمالية للاسنان الاكريكلية. ثباتية اللون للاسنان الاكريكلية مهمة جدا كعامل مؤثر على جمالية الاسنان، سوائل الصبغات مؤثرة على الاسنان عند غمرها لمدة طويلة وبالتالي تؤدي الى تعويض اللون الطبيعي للاسنان الطبيعية. السوائل تشترك بالزيادة التغير اللون الطبيعي وتعطي تعويضات غير مقبولة للاسنان الاكريكلية.في هذه الدراسة تم استخدام (128) غمرت في ثلاث انواع من السوائل الملونة وهي( القهوة، الشاي والكولا) كمجاميع للفحص وبالاضافة الى المجموعة القياسية وهو الماء المقطر. ثباتية اللون تم قياسه للاسنان الاكريكلية بواسطة جهاز(spectrophotometer). التغير باللون تم قياسه للاوقات التالية وهي( 24 ساعة، اسبوع واحد، اسبوعين والشهر واحد) بعد الغمر بالسوائل المستخدمة في هذه الدراسة.اظهرت النتائج من خلال استخدام المتغيرات المعتمدة في كل الفحوصات ان هناك اختلاف كبير بين المجاميع في التحليل الاحصائي باستخدام الاختبار(ANOVA) و(LSD) ما عدا الكولا وجد بانه اكثر متغير من المحاليل وذلك لانها تتكون من مواد حامضية وهو حامض الفسفوريك التي تؤدي الى تاكل سطح السن وايضا صبغة نقية اكثر من المحاليل الاخرى. يمكن الاستنتاج بانه الاسنان الاكريكلية اكثر عرضة الى تغير اللون ويعتمد كمية تغير اللون في كل مجموعة زيادة بالشكل تناسبي مع زيادة الوقت.


Article
Color Stability of Different Aesthetic Arch-wires after Immersion into Different Types of Mouthwashes (In Vitro Study)

Authors: Lubna Maky Hussein لبنى مكي حسين --- Nidhal H. Ghaib نضال حسين غايب
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2017 Volume: 29 Issue: 3 Pages: 100-105
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Because of the demands for aesthetic orthodontic appliances have increased, aesthetic archwires have been widely used to meet patient's aesthetic needs. The color stability of aesthetic archwires is clinically important, any staining or discoloration will affect patient’s acceptance and satisfaction. This study was designed to evaluate the color stability of different types of aesthetic archwires after immersion into different types of mouth washes.Materials and methods: Four brands of nickel titanium coated aesthetic arch wires: Epoxy coated (Orthotechnology and G&H) and Teflon coated (Dany and Hubit) were evaluated after 1 week, 3 weeks and 6 weeks of immersion into two types of mouthwashes (Listerine with alcohol and Listerine without alcohol). Color change measurements were performed by using spectrophotometer VITA Easyshade Compact according to the commission Internationale de I’Eclairage L*a*b* color space system.Results: The results of this study showed that there were highly significant differences in color change values among all brands of aesthetic archwires at various immersion media. On the other hand, a significant difference was found between Dany and Orthotechnology aesthetic archwires at 1 week immersion in distilled water. Listerine with alcohol mouthwash produced more color changes of aesthetic archwires and color change value increases with the time of immersion.Conclusions: All brands of aesthetic archwires showed different degrees of color changes but most of these changes were not visible or clinically acceptable


Article
The Effect of Thickness on The Color Parameters of The Vinyl Addition Maxillofacial Elastomer

Authors: Abdullah J. Mohammed --- Radhwan H. Hasan
Journal: Medical Journal of Babylon مجلة بابل الطبية ISSN: 1812156X 23126760 Year: 2014 Volume: 11 Issue: 3 Pages: 699-704
Publisher: Babylon University جامعة بابل

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Abstract

Aim of the study : The study investigated the effect of material thickness on color parameters of maxillofacial silicon . Materials and methods :sixty samples made of silicone rubber. Samples ( 20 * 10 * 3) mm length , width , thickness, and (20 * 10 * 1.5) mm length, width, and thickness were divided into three groups, white, yellow and pink ( 10 samples a thickness of 3 mm and 10 samples thickness of 1.5 mm in each group) . And then the samples were tested for recording color parameters .Results : There was a significant difference for the three color values at different thicknesses, where the value of * L and a * in the three groups decreased as thickness increased while the b * value rose up with the thickness . Conclusions: The increase in the thickness of the maxillofacial silicon associated with a decrease in the value of L * , a * and a rise in the value of b *.

أهداف الدراسةِ: تَحرّتْ الدراسةُ تأثيرَ سمك مادة مطاط السليكون الوجه الفكي والمستعملة في تعويض اجزاء الوجه والفكين المفقودة على مقاييسِ لونَ المادة لما له من تاثيرعلى جمالية الجزء المصنع واندماجه مع بقية اجزاءالوجه. المواد وطرائق العمل: ستون عينة صنعت مِنْ مطاطِ السيليكونِ الوجه فكي. 30 عينة تحمل الابعاد (20*10*3) مليمتر طول ، عرض، وسُمك،و 30 عينة اخرى بالابعاد(20*10*1.5) مليمتر طول ، عرض، وسُمك قسمتَ إلى ثلاث مجموعاتِ أبيضَ ، أصفرَ ووردي (10عينات بسمك 3ملم و10 عينات بسمك 1.5ملم في كُلّ مجموعة من الالوان الثلاثة). وبعد ذلك إختبرَت العينات لتَسجيل مقاييس اللونَ. النَتائِج: كان هناك اختلاف معنوي لقيم اللون الثلاثة عند اختلاف السمك حيث ارتفعت قيمة *Lوa* في المجموعاتِ الثلاث بانخفاض السمك بينما ارتفعت قيمة b*بارتفاع السمك. الاستنتاجات: الزيادة في سمك مادة مطاط السيليكون الوجه الفكي تترافق مع نقصان في قيمة L* وa* وارتفاع في قيمة b*.


Article
Color Stability of Different Aesthetic Archwires (An In vitro study)

Authors: Zainab Th. Noori --- Nidhal H. Ghaib نضال حسين غايب
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2016 Volume: 28 Issue: 1 Pages: 164-168
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Coated aesthetic archwires are currently the existing solutions for the esthetic problem, but the color ofthese archwires tends to change overtime. This study was aimed to evaluate the color stability of different types ofesthetic archwires from four different companies at different time periods after immersion of two different stainingdrinks which are tea and Pepsi cola.Materials and methods: 48 specimens were prepared, each specimen contains 10 aesthetic archwires; and weredivided according to type of solution into two groups: A (tea) &B (Pepsi cola); each group contained 24 specimens(12 specimens were immersed in the staining solution as 4 specimens for each time intervals and 12 specimens wereimmersed in distilled water as control group). Each subgroup contains one specimen from each company. Colormeasurements were performed by means of a computed spectrophotometer according to the CommissionInternationale de I’Eclairage L*a*b* system, and color changes (ΔE*) and National Bureau of Standards units.Results: Both staining solution caused color change in variable degree and the higher amount of color instability wasfound for the archwires from the Hubit Company while the least amount of color change was for the archwires fromthe Orthotechnology Company.Conclusion: The tea caused highly significant change on the aesthetic archwires which is higher than the effect ofthe Pepsi cola


Article
Effect of different staining materials on color stability of sapphire brackets bonded with different types of light cure orthodontic adhesives (An in vitro study)

Authors: Alaa Faleh Albo Hassan الاء فالح البوحسن --- Nidhal H. Ghaib نضال حسين غايب
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2015 Volume: 27 Issue: 2 Pages: 136-141
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The demand for better esthetic during orthodontic treatment has increased nowadays, so orthodontistsstarting using esthetic arch wires, brackets and ligatures.Tooth colored brackets were introduced in different types ofmaterials. Sapphire ceramic brackets are one type of esthetic brackets and their color stability remains the mainconcern for the clinicians and patients at the same time .The present study design to evaluate the effect of three different staining materials (pepsi, black tea and cigarettesmoke) on the stainability of sapphire ceramic brackets bonded with three types of light cure orthodontic adhesiveswhich include: Resilience, Enlight and Transbond.Materials and Methods: The sample consisted of three hundred sixty sapphire brackets. The brackets were dividedaccording to bonding materials into three groups each group consist of one hundred twenty brackets, then eachsubgroup farther subdivided into four groups according to the material they were immersed (distilled water, blacktea, Pepsi and cigarette smoke) with thirty brackets each, then Each group with ten brackets farther subdividedaccording to time interval of immersion in each media into three groups one day, seven days and fourteen days at37°C in the incubator.A UV-Visible spectrophotometer (Shimadzu, UV -1800) was used to perform a light absorptiontest.Results: ANOVA and LSD post Hoc tests were used to identify the significant effects of the staining materials at asignificance level P ≤ 0.05.It was found that the immersion time gradually influenced the color stability of the adhesivematerials with sapphire brackets with the highest activity observed at fourteen days interval. The brackets bondedwith Resilience light cure adhesive are the most type affected by staining materials, then followed by the bracketsbonded with Transbond and finally the brackets bonded with Enlight light cure adhesive. For the staining materials itwas found that the cigarette smoke is the most powerful staining material, followed by tea and finally pepsi.Conclusions: From the above result we can conclude that the type of adhesive must take in consideration when theesthetic brackets have been used


Article
The effect of Beverages on Color Stability of Highly Impact Acrylic Resin

Author: Ammar Kh. Al-Noori
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2015 Volume: 15 Issue: 1 Pages: 329-339
Publisher: Mosul University جامعة الموصل

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Abstract

Aim: To evaluate the effect of beverages (Distilled water ,Artificial orange, Zamzam water, Natural orange, Cola, coffee, and Tea) on the color stability of the highly impact resin. Materials and methods: Total samples of this research were (48) samples of highly impact resin were prepared 30 * 20 * 1.5 mm (length, width and thickness). Six samples were immersed in each type of beverage. The last six sample (control) without any type of beverage (after control group and other beverage groups were evaluated after (3 hours, 9 hrs, 18 hrs, 36.5 hrs, and 73 hrs) immersion time intervals by using (CIE L* a* b* ) system. the results of this research were analyzed statistically by ANOVA and Duncan’s multiple range test. Results : There was no significant difference among beverages at immersion time intervals (3 hrs, 9 hrs, 18 hrs, and 73 hrs) except at (36.5 hrs) there was a significant difference, also the results showed that there was no significant difference among immersion time intervals for different types of bever-ages. Conclusions: among beverages coffee and tea showed unaccepted value of ΔE at all immersion time intervals except at (9 hrs) while cola showed an accepted values of ΔE except at (3 hrs) of immer-sion where ΔE value was unaccepted.


Article
Evaluation the Effect of Staining Agents on the Color Stability of Composite Resins that Polished at Different Interval Times (an in Vitro Study)

Author: Shaymaa SH. Hassan
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2016 Volume: 16 Issue: 1 Pages: 30-40
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: This study investigated the effect of polishing times (immediately, 1 hour and 24 hour after light curing) and staining solutions on the color stability of two composite resins. Materials and Methods: Nanocomposite (Filtek Z350) and microhybrid composite (Valux plus) were used. Sixty discs (8mm diameter×2mm height) were made for each composite, and divided into four groups: the first group was polished immediately after light curing; second group was polished after 1 h; third group was polished after 24 h of curing; and the fourth group was the control. Color was measured with spectrophotometer. After baseline color measurements, the specimens of each group divided into three subgroups; specimens of first subgroup were immersed in coffee; specimens of second subgroup were immersed in orange juice; specimens of third subgroup were immersed in distilled water, after 7 day of immersion, the color was measured again and ΔE were calculated. Statistical analysis: Two-way ANOVA, Duncan's Multiple Range test and t-test. Results: The influence of polishing times and staining solutions on color change was significant. Polishing 24 hours after curing presented lowest ΔE value. Coffee promoted more color change than orange juice and distilled water, Filtek Z350 showed lower ΔE than Valux plus. Conclusions: Immediate polishing negatively affect the color stability of composite resins, coffee had a significant influence on discoloration of composite resins. The nanocomposite showed higher color stability than microhybrid composite.


Article
The effect of some chemical disinfection solutions on the color stability of vinyl addition cured silicon

Author: Ibtehal H AL –Zubaidy
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2017 Volume: 17 Issue: 1 Pages: 68-75
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: The study investigated the effect of curing methods and the effect of some chemical disinfection solution on the color parameters of the vinyl addition silicon maxillofacial materials. Materials and methods: 30 samples were made from maxillofacial silicon rubber. The samples (20*10*3)mm length, width, and thickness, were divide into two group ( cold and hot curing )15 sample for each group , 5 sample for each disinfection solution that used in this study and then tested to record the color parameters . Results: The result showed there was significant differences between (group 1 and group 2 ) in all L,a,b values and more changes was found in group 1(cold cure ) except in L1 and b3 the more changes was found in group 2(hot cure ). the more color changes was found in the samples that immersed in Sodium hypochlorite. the chlorhexidine showed less value of color changes than the other type. Conclusion: Translucency of the cold cured samples was higher than that of the heat cured samples, due to the effect of processing heat . the more color changes was found in the samples that immersed in Sodium hypochlorite. the chlorhexidine showed less value of color changes than the other types because it chemically inert and acting through saturation.


Article
Assessment of zirconium oxide nano-fillers incorporation and silanation on impact, tensile strength and color alteration of heat polymerized acrylic resin

Authors: Ihab N.S ايهاب نبيل --- Hassanen K.A. --- Ali N.A. علي نعمة
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: special issue 2 Pages: 36-42
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The mechanical strength and color stability of poly methylmethacrylate (PMMA) remains far from idealfor maintaining the longevity of denture. The purpose of this study was to assess impact, tensile strength and colorstability of heat polymerized denture base after addition of salinated and non-salinated zirconium oxide (ZrO2) nanofillers.Materials and methods: zirconium oxide nanofillers were incorporated into (PMMA) denture base by free radical bulkpolymerization. The nano-particales were Silanated by coating with a layer of trimethoxysilypropylmethacrylate(TMSPM) before dispersed and sonicated in monomer (MMA) in two percentages of 3% and 5% by weight. Then itwas mixed with acrylic powder as general conventional method. One hundred and seventy five specimens wereprepared for this study. fifty bar shapes specimens (80mm x 10mm X 4mm) for impact strength test, another fiftydumbbell shaped specimens (75mm × 12.75mm × 2.5mm ) were prepared for tensile strength test. On the otherhand, seventy five disc shaped specimens (50mm diameter and 0.5mm thickness) were prepared for color stabilitytest. They were divided into two groups according to the nanofillers used ; silanated and non-silanated ZrO2nanofillers, for each group Three subgroups were prepared (one control and two(3% and 5%) for the silanated andnon-silanated ZrO2 nano-fillers. Impact strength test was carried out with charpy type impact testing instrument. Whiletensile strength test were done by using Jain Qiao equipment system. . On the other hand, color stability wasobjectively assessed by using a spectrophotometer device after 48 hours immersion in three different solutions(distilled water, cola and tea) and the amount of light absorption was calculated. Impact and tensile strengthmeans (in MPa) and color stability means (in nm) were analyzed statistically by analysis of variance and thecomparative T-test and least significance test (LSD).Result: Significant increase in impact strength occur in acrylic reinforced with 5% wt silanated (ZrO2) nanofillers , butnon significant increase was observed at 5% wt non-silanated (ZrO2) nanofillers when compared with control group.On the other hand, there were non-significant improvements in the tensile strength for all groups of (ZrO2)reinforcements. While for the color stability test data showed significant increase in the light absorptions forspecimens reinforced with (ZrO2) nanofillers when compared with control group. on the other hand, there were nosignificant difference observed between specimens reinforced with non-silanated and silanated (ZrO2) nanofillers.Conclusion: the findings of this study showed that Silanaized ZrO2 nano-fillers is effective in improving impact strengthwhile it was not effective in improving the tensile strength, the maximum increase in impact strength was observed indenture base nano composite containing 5% wt of silanated ZrO2 nano-fillers. On the other hand, significant colordifferences were detected between control group and specimens incorporated with zirconium oxide nano-fillers atdifferent immersion solutions


Article
The Effect of Artificial Accelerated Aging on The Color of Ceramic Veneers Cemented With Different Resin Cements (A Comparative In Vitro Study)

Authors: Shatha Kh. Hussain --- Inas I. Al-Rawi
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2017 Volume: 29 Issue: 1 Pages: 39-46
Publisher: Baghdad University جامعة بغداد

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Background: Color changes that are detectable to human eye can affect the esthetic appearance of ceramic veneers. The purpose of this study was to evaluate and compare the effect of artificial accelerated aging on the color of ceramic veneers cemented with different resin cements.Materials and Methods: Sixty discs were prepared with 0.5 mm thickness, 30 discs made from IPS e.max press (Ivoclar Vivadent) and 30 discs were made from VITA Enamic (VITA Zahnfabrik). The discs were cemented with three resin cements: Variolink Veneer MV 0 shade (Ivoclar Vivadent), Rely X veneer Translucent shade (3M ESPE) and NX3 Nexus Clear shade (Kerr Corporation) with 0.1 mm thickness. The spectrophotometer Easyshade Advance was used to measure the color parameters (Lightness, axis a* of chroma and axis b*of chroma) immediately after cementation, after 150 and 300 hours of aging. The specimens were subjected to artificial accelerated aging in Accelerated Weathering Tester. Color change greater than 3.3 was considered unacceptable. One-way ANOVA, paired t-tests and Bonferroni adjusted t-test were used for statistical analysis (p <0.05).Results: Artificial aging caused high significant color change in both ceramic types, but there were non-significant difference in color change among the three resin cements used. The color change was between1.997-14.8 after 150 hours and it was between 2.179-15.68 after 300 hours. The color change of e.max discs after aging were within acceptable limit<3.3 whereas Vita Enamic specimens had shown unacceptable color change >3.3 after aging.Conclusions: The majority of color change after aging related to veneering materials while resin cement have only slight effect on color change after aging. IPS e.max had shown an acceptable color change after aging, so it is suitable for fabrication of restorations in esthetic zone while Vita Enamic should not be used in esthetic zone since it has poor color stability according to the results of this study

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