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Article
The effect of low shrinkage dental composite on the fracture strength of weakened premolar teeth (An in vitro study)

Authors: Ali H. Al –Khafaji --- Rasshaa I. Suhail
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2011 Volume: 23 Issue: 3 Pages: 30-36
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: The aim of the study was to evaluate and compare the fracture resistance of weakened maxillary
premolar teeth with MOD preparations restored with low shrinkage new Silorane based composite (Filtek p90) in
comparison to low shrinkage methacrylate based composite (1-packable Filtek p60,2- nanohybrid Tetric Evoceram ).
Materials and Metods: Fifty human adult maxillary premolar teeth recently extracted for orthodontic purpose were
selected. These teeth received MOD cavity preparations with no proximal boxes. The teeth were then randomly
divided in to five groups (n=10), according to the material used for restoration: Group A (Teeth were not prepared ),
Group B (Teeth, with MOD cavity preparation were not restored.) Group C (Teeth, with MOD cavity preparation were
restored with Filtek p60 packable composite), Group D (Teeth, with MOD cavity preparation were restored with Tetric
Evoceram nanohybrid composite) Group E (Teeth, with MOD cavity preparation were restored with Filtek p90 silorane
based composite). These specimens were then stored in an incubator at 37Ċ for one week, at 100% humidity in
deionized water before test. Cuspal fracture resistance was determined using compressive testing machine.The
fracture specimens in group C,D and E were stained with 1%methylene- blue dye for 24 hours then examined by
stereo microscope ×40 to evaluated the mod of failure, the data were staistically analyzed using Analysis of variance
test (ANOVA), LSD test and student t-test .
Results: The results showed that there’s a high significant improvement of the fracture resistant of restored teeth using
posterior composite as compared to the unrestored ones, but; ther’s no difference of the type of the posterior
composite material used on the fracture resistance of the weakened teeth, while the sound teeth remained the
strongest teeth compared with all the other groups. Examination of the fractured specimens of GC, G D and G E
using stereo microscope revealed that for Group C and group D,70%and 50% cohesive failure respectively while for
group E 70% showed adhesive failure.
Conclusion: Posterior composite resin restoration whatever material type used for packing it, showed a great
improvement in the resistance to cuspal fracture, Silorane based composite show little improvement in fracture
resistance by means value in comparison to methacrylate based composite although statistically there is no
significant difference between them.
Key words: low shrinkage composite, fracture strength of teeth, silorane based resin composite. (J Bagh Coll Dentistry
2011;23(3): 30-36).

Keywords


Article
The influence of different light curing systems with different curing depth on the microhardness of packable composites.

Authors: Ali H. Al – Khafaji --- Ala`a J. Kadum
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2010 Volume: 22 Issue: 1 Pages: 1-6
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: Adequate polymerization of resin composite is considered to be very important factor. The aim of this
study was to evaluate and compare the influence of different light curing system (conventional QTH, LED and PAC
units) with different polymerization depth (0-1,1-2, 2-3, 3-4 and 4-5 mm) on microhardness of two types of packable
composite (Filtek p60 & Surefil).
Materials and Methods: Two types of packable composites (Filtek p60 and Surefil) were tested. Thirty hemi cylindrical
specimens (5mm diameter x 6mm height) were made for each material. Photo-activation was performed using
conventional QTH, light emitting diodes (LED) or plasma arc (PAC).Exposure times were 40 seconds for QTH and LED
lights, and 12 seconds for the PAC light. After one day of storage, the microhardness test was measured at 5mm
depth intervals (0-1, 1-2, 2-3, 3-4 and 4-5 mm).
Results: The microhardness of packable composite resins (Filtek p60) showed a significantly higher microhardness
than packable composite (Surefil) in all light activation systems and in all depth intervals. The LED light curing system
produced superior mean microhardness value followed by conventional QTH and PAC light curing systems
respectively. And all of the tested composite resins groups with the three different types of light activation systems
showed a significant decrease in the microhardness with the increase of depth.
Conclusion: The microhardness of packable composite is affected by the type of materials, light curing systems and
curing depths.
Key words: microhardness, packable composite, light curing systems, curing depths. J Bagh Coll Dentistry 2010;
22(1):1-6

Keywords


Article
An evaluation of the effect of curing systems and water storage on the fracture toughness of two types of composite resin filling materials with different organic matrix composition (in vitro study)

Authors: Ali H. Al – Khafaji --- Zahraa N. Al – Wahab
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2006 Volume: 18 Issue: 1 Pages: 1-5
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: Chipping and bulk fracture are major contributors to clinical failures of composite restorations. Fracture toughness (KIC) quantifies susceptibility for fracture. Halogen light curing units have some specific drawbacks, such as decreasing light output with time. This may result in a low degree of monomer conversion of the composite, which is undesirable, as it can adversely affect mechanical properties including fracture toughness. This study was conducted to evaluate the effect of conventional light cure unit (Astralis – 5), light emitted diode (Radii) and water storage on the fracture toughness of packable composite (Filtek P60) and microfilled hybrid composite(Glacier).
Materials and Methods: KIC was determined by preparing 128 single – edge notched beam test specimens (2X4X20 mm with a 3mm long notch on one edge). The composite specimens were cured by Astralis – 5 or Radii and were subjected to 3 – point bending test (without aging), after 1 day, 7 days, and 28 days storage in distilled water. Student t – test followed by ANOVA (P<0.01) were used to analyze the results.
Results: The fracture toughness values were highly significant when using Radii light cure unit (for both types of composites), and the fracture toughness values for P60 composite were highly significant.
Conclusions: Water aging from 7 days to 28 days didn't produce significant effect in the fracture toughness values for P60 composite, but it led to a highly significant reduction in the fracture toughness values for the Glacier composite. Resin containing Bis – GMA showed higher fracture toughness values than UDMA based resin.
Key words: Fracture toughness, (J Bagh Coll Dentistry 2006; 18(1) 1-5)

Keywords


Article
The effect of different finishing and polishing systems on surface roughness of new low polymerized composite materials (An in vitro study)

Authors: Mustafa R. Abdurazaq مصطفى عبد الرزاق --- Ali H. Al-Khafaji علي الخفاجي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 2 Pages: 24-30
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Adequate finishing and polishing of resin composites is a prerequisite for high-quality esthetics andenhanced longevity of resin-based restorations. Finishing and polishing of resin composites are important proceduresin restorative dentistry. Finishing refers to gross contouring of a restoration to obtain the desired contour. However,polishing refers to smoothness as well as to reduction of the scratches created by the finishing instruments.Materials and methods: Four types of composite materials where used in this study, FiltekP90 (3M ESPE, St.paul, U.S.A),Tetric Evoceram (Vivadent, Schaan, Liechtenstein), FiltekZ250 (3M ESPE, St.paul, U.S.A), FiltekP60 (3M ESPE, St.paul,U.S.A), also two polishing systems which are: Optrapol (Ivoclar Vivadent) and Enhance (Dentsply) and one Siliconecarbide finishing paper. A total number of 160 disc shaped specimens were produced in a circular steel molds with acircular hole in its center , with a diameter of (10×3mm), specimens where divided into four groups of 40 specimenseach (10 samples from each composite type) according to the finishing/ polishing protocol used as follows Group A:control without finishing and polishing. Group B: polishing using optrapol polishing system. Group C: polishing withEnhance polishing system. Group D: finishing only with silicone carbide finishing paper(600 grit). Except for the controlgroup Specimens first are finished using silicone carbide paper 600 grit for obtaining a baseline surface roughnessbefore the application of polishing systems, the At the completion of the finishing and polishing instrumentation, thespecimens were ultrasonically cleaned in an ultrasonic unit with distilled water for two minute. The surface roughnesswas measured by using a portable surface roughness tester (SRT 6210).Results: The result showed that all the composite materials under control group that cured using mylar strip exhibitedthe least surface roughness values (best smoothness). All the composite materials produced smoother surface whenpolished with optrapol system than with Enhance system. For the silicone carbide finishing paper we found that allthe materials produced high surface roughness values than with other finishing and polishing systems and there wasno significant difference between the composite materials.Conclusion: FiltekP90 exhibited the smoothest surface finish compared to the other composite materials used in thisstudy while FiltekP60 exhibited the roughest surface finish compared to the other composite materials used in thisstudy.


Article
The effect of in office bleaching on surface roughness and micro-hardness of newly developed composite materials (In vitro study)

Authors: Noor S. Nadhum نور ناظم --- Ali H. Al-Khafaji علي حسين الخفاجي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 2 Pages: 24-29
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Alterations in the microhardness and roughness are commonly used to analyze the possible negativeeffects of bleaching products on restorative materials. This in vitro study evaluated the effect of in-office bleaching(SDI pola office +) on the surface roughness and micro-hardness of four newly developed composite materials(Z350XT –nano-filled, Z250XT-nano-hybrid, Z250-mico-hybrid and Silorane-silorane based).Materials and methods: Eighty circular samples with A3 shading were prepared by using Teflon mold 2mm thicknessand 10mm in diameter. 20 samples for each material, 10 samples for base line measurement (surface roughness byusing portable profillometer, and micro-hardness by usingDigital Micro Vickers Hardness Tester), and 10 samples forafter bleaching measurement. The appropriate bleaching procedure was performed on the top surface of testgroups for 90 minutes total bleaching period. Then surface roughness and hardness were tested at the end of theduration. Statistical analysis was carried out using ANOVA, LSD and t-test.Results: There was a highly significant increase in surface roughness of all tested groups after bleaching. There is ahighly significant increase in micro-hardness for Z250, there is decrease in Micro-hardness for siloraneand Z250xt andthere is a non-significant increase in micro-hardness of Z350xt.Conclusion: bleaching has a negative effect on surface roughness of all the tested materials, as surface roughnessincreased after bleaching. Micro-hardness is a material dependent, there is different reaction to bleachingdepending on the resin, load and size of the fillers used in the materials. Nano-filled composite is the material that hasbetter performance than the other tested materials, as it is the material that has the least affection by bleaching


Article
Immunohistochemical Study of Estrogen, Progesterone Receptor and Her-2neu Oncogene with Her-2neu Biomarker Estimation by ELISA Technique in Primary Breast Cancer before Chemical Therapy
دراسة نسيجية مناعية لمستقبل هرمون الاستروجين والبروجستيرون والهير 2 نيو الورمي مع حساب العلامات البايولوجية للهير 2 نيو عن طريق تقنية اللايزا في مريضات مصابات لسرطان الثدي قبل العلاج الكيمياوي

Authors: Ali H. Al-Khafaji علي حسين الخفاجي --- Ayad M.A. Fadhil اياد محمد علي فاضل --- Mohammed A. Hameed محمد اياد حميد
Journal: Iraqi Journal of Science المجلة العراقية للعلوم ISSN: 00672904/23121637 Year: 2014 Volume: 55 Issue: 1 Pages: 132-144
Publisher: Baghdad University جامعة بغداد

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Abstract

Breast cancer is one of the comments malignant tumors worldwide especially in Iraq; it is a leading cause of death in Iraqi women. Determination of estrogen and progesterone receptors status is helpful in selecting the patients most likely to receive benefit from endocrine therapy, and provide prognostic information on recurrence and survival since their expression is related to the degree of the tumor differentiation. From November 2012 to March 2013, 150 breast cancer patients at Al-Amal Hospital in Baghdad were attended to start treatment of disease for the first time. All patients included in this study did not receive chemotherapy. Patients were asked to bring their paraffin embedded tissue blocks to participate in estrogen, progesterone and Her-2/nue receptors estimation. Blood samples were also collected from the patients to estimate positive Her-2nue cases in serum. Age distribution in women with breast cancer showed that 44%of cases at age group (40 – 49) years. 23% of the patients had a positive family history (first and second degree). Histological types of breast carcinoma showed that 82%, 14% and 4% were ductal, lobular and mixed carcinoma respectively. The Makee classification showed that Grade I, II, and III were detected in 10%, 64% and 26% respectively. TNM staging revealed that 16% of the patients were recorded in stage I, 44% in stage II, 32% in stage III and 8% in stage IV. It was demonstrated that 72% and 70% of breast carcinomas were positive for ER and PR respectively; both markers correlated with age, family history, type, histological grade and stage of the disease. Her-2/neu showed 28% expression in Iraqi breast cancer cases. HER2/neu over-expression (>15 ng/ml) was observed in 36 out of 150 patients (24%) Her-2/neu serum level at ELISA diagnosis and in 42 out of 150 (28%) at immunohistochemistry method (IHC).There were significant (P <0.001) association between tissue HER-2/neu and serum HER-2 levels. Detection Her-2/neu in serum by ELISA technique could be used as a method for detection with high rate reached to 78% after mastectomy, also it considered as an excellent method for follow up.

يعد سرطان الثدي احد اكثر انواع السرطان شيوعا في العالم واحد اهم اسباب الوفاة بين نساء العراق ولقد كان لاكتشاف مستقبلات الهرمونات (استروجين و بروجستيرون) فضل كبير في اختيار المريضات للخضوع للعلاج الهرموني ولتوقع فترة العيش بعد العلاج وامكانية رجوع الورم مرة اخرى وذلك للعلاقة بين درجة الورم ونسبة تمثيل مستقبلات الهرمون على سطح الخلايا, يقوم البحث على اساس قياس نسبة ER, PR &HER2neu في النسيج ومصل الدم وملاحظة العلاقة بين مستوى المستقبلات والحالة الاكلينيكية في نساء عراقيات مصابات بسرطان الثدي قبل وبعد الخضوع للعلاج الكيميائي, تم بدأ الدراسة من تشرين الثاني 2012 الى اذار 2013 في مستشفى الامل وتم اختيار المشخصات حديثا بالاصابة بسرطان الثدي وقبل بدأ العلاج الكيميائي للمشاركة في الدراسة , تم اخذ النسيج المنطمر في البارافين وعينة من الدم من 150 مريضة لمعرفة نسبة الHER2neu الموجبة (اهم بارامتر في الدراسة) 44%من النساء المشمولات في الدراسة كن بين 40-49سنة, 23% لهن اقارب من الدرجة الاولى والثانية مصابات بالمرض, 82% كان من نوع سرطان القنوات,14% من نوع قصيبي و 4% من النوع المختلط, 64% من الدرجة الثانية,10% من الدرجة الاولى و16% من الدرجة الثالثة حسب تصنيف SBR, باستخدام تصنيف TNM 16% في المرحلة الاولى 44% في المرحلة الثانية.32% في المرحلة الثالثة و8% في المرحلة الرابعة وكلاهما علامات مرتبطة مع التقدم في العمر والتاريخ العائلي ونوع ودرجة النسيجية ومرحلة المرض. التحليل المناعي immunohistochemistry over expression) ( كشف عن 42(28%)حالة زيادة او افراط في التعبير للجين الورمي HER2neu وباستخدام تقنية الفحص المناعي المرتبط بالانزيم ELISA كانت نسبة فرط التعبير 22% بمتوسط يبلغ 17.9 نانوغرام/مل بمدى 12.8_29.9نانوغرام/مل P value<0.001, r=0.53. هناك فروقات معنوية (P <0.001) مرتبطة ما بين مستويات HER-2/neu اللنسيجية و HER-2 مصل الدم. الكشف عن مستقبلات ال Her-2neu في مصل الدم بواسطة تقنية ELISA يمكن أن تستخدم كوسيلة للكشف مع نسبة عالية وصلت إلى 78٪ بعد عملية استئصال الثدي، كما أنه تعتبرها وسيلة ممتازة لمتابعة العلاج(follow up). تعد تقنية التحليل المناعي اختبار سهل نسبيا ويمكن استخدامه لمراقبة فعالية انسجة الثدي.

Keywords

Breast Cancer --- ER --- PR --- Her2/neu

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