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دراسة لتحويرات نانوية مختلفة لسطح زرعة الاسنان من معدن التيتانيوم النقي تجاريا باستعمال الطريقة الكيميائية وطريقة التبخير الحراري : تقييم ميكانيكي ونسيجي == Study Different Nano Surface Modifications On CPTi Dental Implant Using Chemical And Thermal Evaporation Methods : Mechanical And Histological Evaluation

اسم المؤلف: بان ناهل شكر
اسم المشرف: رغداء كريم جاسم
الموضوع العام: طب الاسنان
السنة: 2014
الموضوع الدقيق: صناعة الاسنان
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Background : Dental implants provide a unique treatment modality for the replacement of lost dentition. The clinical success of implants has been achieved not only because of the mechanical strength or cellent biocompatibility of the implant material but also owing to other characteristics such as surface properties.Aims of the study : The goal of this study was to consider the role of nanoscale topographic modification of commercial pure titanium dental implant using a thermal deposition and chemical etching methods for the purpose of improving osseointegration.Materials and methods : Commercial pure titanium rod was machined into 40 dental implants. Each implant was machined in diameter about 3mm, length of 8mm (5mm was threaded part and 3mm was flat part). Implants were prepared and divided into 4 groups according to the types of surface modification method used : 1st group (10 implant) machined surface i.e remained without nano surface modification (control),2nd group include (10 implant)etched with 15N H2SO4 and 30% H2O2,3rd group include (10 implant)were coated with nano CPTi powder by thermal evaporation deposition technique,4th group (10 implant)were chemically etched with H2SO4 and H2O2 method to obtain a nano feature then coated with nano powder of CPTi by thermal evaporation deposition technique.Nano surfaces were characterized by scanning electron microscope (SEM), Xray diffraction (XRD), atomic force microscope (AFM), thickness measurement and microscopical examination for the invitro experiments. For the invivo part of study, the tibia of 10 white New Zealand rabbits were chosen as implantation sites. The tibia of each rabbit received two screws. Biomechanical test was performed after two weeks healing periods. Implants from eight animals were tested for the torque required to remove the implantfrom the bone and the other two animals were prepared for histological examination.Results : For invitro results, scanning electron microscope showed that chemical etching of Ti substrate becomes highly porous and has surface consisting of nano_sized pits and the combination of chemical etching and thermal evaporation of nano Ti showed nano rod like structure. The results of removal torque means value after 2 weeks of implantation showed that, there was a gradual increase in the removal torque mean values in the studied groups as a follow (M±SD) : 12.625 N.cm ± 0.517 machined surface, 30.500 N.cm ± 4.071 chemically etched, 46.875 N.cm ± 5.938 nano CPTi coating by thermal evaporation method, 51.250 N.cm ± 5.175 combination method of chemical etching and nano CP Ti coating. In addition, the histological analysis showed improved quality of bone in response to the nano surface modified screws, especially the combination treated implants show a well developed mature bone characterized by a well developed bony threads and haversian canal. Conclusion : The biomechanical and biological properties of the bone - implant interface associated with the nano modified implants were improved comparing to the unmodified implants. All nano modified CP Ti seems to be well tolerated by the bone since no adverse tissue reaction was evident and they have better mechanical properties and excellent biocompatibility through the improved performance regarding the bone implant contact area than the untreated implants.

نقييم الالفا اميليز والكورتيزول في اللعاب كمؤشرين جيويين للتوتر النفسي وعلاقتها بامراض المفصل الصدغي بين عينة من طلاب كلية طب الاسنان == Assessment of Alpha - Amylase And Cortisol As Salivary Psychological Stress Markers In Relation To Temporomandibular Disorders Among A Sample of Dental Students

اسم المؤلف: سرمد قيس علي
اسم المشرف: رجاء هادي الجبوري
الموضوع العام: طب الاسنان
السنة: 2014
الموضوع الدقيق: طب الاسنان
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Background : University dental students perceived a higher level of stress prior to each examation especially the final. Therefore, there is a need for a useful noninvasive biomarker for measuring acute stress in those students. Many studies considered salivary alpha - amylase as a stress biomarker that is most often used in conjunction with cortisol. Understanding of the exact association between these two salivary stress markers are poorly established. Using a Helkimo anamnestic and clinical dysfunction scoring index for temporomandibular disorders can give a better insight about the association between these markers and temporomandibular joint disorders.The aims of study : was to evaluate the levels of salivary alpha - amylase and salivary cortisol in stressed students with temporomandibular joint disorders and the differences between these markers in relation to temporomandibular joint disorders students. This might give a better understanding to the role of psychological stress as an etiological factors for developing temporomandibular joint problems.Subjects, materials and methods : A total eighty (60 study and 20 control) participants aged between 20 and 24 years, were recruited for this study. The participants were final year undergraduate Baghdad university dental students who were examined and gave saliva samples before their final academic examination. Those with temporomandibular joint disorders problems were exposed to psychological stress and included on the study. While, those who were taking corticosteroids or hormone supplementation including oral contraceptives, or having history of head injury, orthodontic treatment, occlusal disharmonies and muscle tenderness due to systemic diseases as fibromyalgia, or having more than 2 missing posterior teeth were excluded. Salivary assay kits (alpha - amylase and cortisol) were used to measure those variables and a Helkimo anamnestic and clinical dysfunction scoring for temporomandibular joint disorders were utilized in this study.Results : There is statistically a highly significant difference of the salivary cortisol and salivary alpha - amylase in the patient group( stress with temporomandibular joint disorders) and control group. The absence of correlation between these salivary markers was founded. Correlation analysis of salivary cortisol with Helkimo anamnestic and clinical dysfunction score shows positive association expressed by significant probability of error (p) value while for salivary alpha - amylase there is no association.Conclusion : This study demonstrates that salivary alpha amylase can be used as a stress biomarker in conjunction with cortisol to assess temporomandibular joint problems due to psychological stress in university students.

الظواهر الوجهية والفموية، عوامل الاكسدة ومضادات الاكسدة في مصل ولعاب مرضى فقر الدم البحر الابيض المتوسط نوع بيتا في مدينة كربلاء == Oro - Facial Manifestations, Oxidative Stress And Antioxidants Markers In Serum And Saliva of Patients With Beta Thalassemia Major In Karbala City

اسم المؤلف: مؤيد صاحب عباس شمسه
اسم المشرف: تغريد فاضل زيدان
الموضوع العام: طب الاسنان
السنة: 2014
الموضوع الدقيق: طب الاسنان
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Thalassemia is a hereditary anemia resulting from defects in hemoglobin production. Beta Thalassemia, which is caused by a decrease in the production of beta globin chains, affects multiple organs and is ssociated with considerable morbidity and mortality. Aims of the study : The aims of this study were to study the oro - facial manifestations in beta thalassemia major patients and evaluation of the oxidative stress status in serum and saliva represented by malondialdehyde as xidative stress indicator and also assessment of serum and saliva antioxidants which are ceruloplasmin and uric acid in beta thalassemic patients with and without periodontitis and compared that with the healthy individuals in addition to investigate the relation between the clinical findings and laboratory investigations.Methods : Eighty seven (87) subjects were consented and contributed in this study, twenty eight (28) thalassemic patients with periodontitis, thirty (30) thalassemic patients without periodontitis and twenty nine (29) healthy subjects that were age matched with the patients. Oral examination has been done for each subject. Serum and saliva sample have been taken from each subject for analysis, to study malondialdehyde as oxidative stress and antioxidants ceruloplasmin and uric acid.Results : Malocclusion was the most common prevalent oro - facial manifestations (60%), followed by rodent face (35%), brown pigmentation of oral mucosa (23%) and incompetent lip (8%). The mean serum and saliva malondialdehyde were significantly higher in thalassemic patients with periodontitis than that in thalassemic patients without periodontitis and healthy subjects (p<0.001), while the mean serum and saliva ceruloplasmin were significantly higher in control group than that in other study groups (p<0.001). The mean serum uric acid was significantly higher in thalassemic patients without periodontitis than that in thalassemic patients with periodontitis and healthy subjects (p<0.001) and the mean saliva uric acid was significantly higher in thalassemic patients without periodontitis (p<0.05) compaired with thalassemic patients with periodontitis and healthy subjects. The results of this study showed that there were no significant correlation between serum and saliva malondialdehyde in any of study groups, while there was a positive significant linear correlation between serum and saliva ceruloplasmin in thalassemic patients with periodontitis (p<0.05), a negative significant linear correlation in healthy subjects (p<0.05) , a positive significant linear correlation in thalassemic patients without periodontitis (p<0.001). The results showed that there was a positive significant linear correlation between serum and saliva uric acid in thalassemic patients with periodontitis (p<0.05), a positive significant correlation in thalassemic patients without periodontitis (p<0.001) and no significant correlation between serum and saliva in healthy subjects. On the other hand there were no significant correlation between serum and saliva (malondialdehyde, ceruloplasmin and uric acid) and clinical attachment loss (p>0.05), except a positive significant linear correlation between clinical attachment loss and salivamalondialdehyde (p<0.05) was found. Conclusions : Malocclusion was the most prevalent oro - facial manifestations of beta thalassemia major patients. Oxidative stress play a significant role in the pathogenesis of beta thalassemia ,which was the main cause of red blood cells destruction represented by significant elevation of serum and saliva malondialdehyde and significant reduction of ceruloplasmin. Also oxidative stress remain contributing factor in periodontal tissue destruction, which was appeared as a significant increased level of saliva malondialdehyde and decreased saliva ceruloplasmin in patients with periodontitis and there was a significant correlation between saliva malondialdehyde and clinical attachment loss

التقييم النسيجي والكيمائي النسيجي المناعي لتاثير الاستخدام على VEGF/ N - acetyl D - glucosamine الموضعي ل شفاء العظم : دراسة تجريبية على الجرذان == Histological And Immunohistochemical Evaluation of The Effect of Local Exogenous Application of VEGF /N - Acetyl D - Glucosamine On Bone Healing : (Experimental Study In Rats)

اسم المؤلف: ایناس فاضل كاظم
اسم المشرف: عذراء يحيى الحجازي
الموضوع العام: طب الاسنان
السنة: 2014
الموضوع الدقيق: الانسجة الفموية
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Background : Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue has been shown to contain numerous cell - to - cell signaling peptides called growth factors. These growth factors are thought to have important regulating effects for bone remodeling and bone healing. Several growth factors are expressed during fracture repair. of these, vascular endothelial growth factor (VEGF), is of particular interest because of its ability to induce neovascularization (angiogenesis). The responses to exogenous VEGF observed that a slow - release formulation of VEGF, applied locally at the site of bone damage, may prove to be an effective therapy to promote human bone repair. N - acetyl glucosamine is a monosaccharide, which are the derivatives of carbohydrates, it helps the body in making several other chemical agents which are used in the formation of bones, muscles and cartilages.N - acetylglucosamine is very effective in providing support for the skeletal system of the humans, and may provide strength to the ligaments and joints, and the skin remains fresh and glowing. Aims of study1. To identify role of local exogenous application of vascular endothelial growth factor and application of N - acetyl - D glucose amine as a biomaterial in bone healing.2. To analyze the expression of Vascular endothelial growth factor, tissue non specific ALP and bone matrix protein (collagen - 1) by immunohistochemistry in created bone defect after application with different biomaterials in a rat model. Materials and MethodsIn this experimental study fifty four male Albino rats, weighting (300 - 400) gram, aged (6 - 8) months were used and maintained under control conditions of temperature, drinking and food consumption. The animals were subjected for a surgical operation of medial sides of both tibial bone ( right side was considered as experimental site ,while left be the control one). The animals were divided into following groups according to the applicable growth factors.A. Contol group the bone defect treated with 1?m of normal saline and its number represented the all number of the following experimental groups as the left side of each animal considered to be the control.B. Experimental group includes ? Group I contains (18) rats, the bone defect treated with 1?ml of Vascular endothelial growth factor. ? Group II contains (18) rats the bone defect treated with 1?ml of Nacetyl D - glucosamine.? Group III contains (18) rats, the bone defect treated with 1?m combination of (VEGF& N - acetyl D - glucosamine).Every single group composed of 18 rats that studied in three periods 3,7,10 days (6 rats for each period). Histologic and immunohistochemical evaluation for VEGF, alkaline phosphatase and collagen type 1 were carried for all animals.Results : A. For Histological findings An early apposition of osteoid tissue was detected in VEGF group. Osteoblast, osteocyte and osteoclast cells count were demonstrated to be with high mean value in VEGF group followed by N - acetyl Dglucosamine group in periods 3,7,10 days post operative of bone defect.Inflammatory phase as first step in bone healing was detected in all study groups at 3 day, and combination group records highest value in the mean of inflammatory cell count in comparisum to others. Finally thestudy demonstrated that exogenous VEGF/ N - acetyl D - glucosamine has a direct effect on osteoblastic activity.B. For Immunohistochemical findings The present result showed positive expression of VEGF by bone marrow stromal cells, adipocytes, mesenchymal stem cells, precursor endothelial cells, and bone cells include osteoblasts and active osteocytes in different periods in all groups but in different score. Therefore, our primarily data provide evidence that VEGF activity is essential for appropriate bone formation and mineralization in response to injury. At day 3, bone marrow stromal cells in combination group records highVEGF expression, VEGF group is the second. At 7 and 10 day VEGF group records a highest VEGF expression in comparisum to other groups. The data showed a high expression for ALP during the formative stages of bone in all groups except combination group shows the lowest count for positive cells that expressed ALP.the present results showed that at day 3, bone marrow stromal cells in VEGF and N - acetyl D - glucosamine group records high collagen type I expression. Conclusion : the study demonstrated that low application of VEGF / Nacetyl D - glucosamine could be an effective therapeutic for bone injuries, these data are promising for a possible future clinical usage.

Assessment of The Oral Findings, Salivary Oxidative Status And Iga Level Among Group of Workers Exposed To Petroleum Pollutants In Al - Daura Oil Refinery

اسم المؤلف: امير سعد حمزة
اسم المشرف: Jamal Noori Ahmed
الموضوع العام: طب الاسنان
السنة: 2014
الموضوع الدقيق: طب الاسنان
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Petroleum is perhaps the most important substance consumed in modern society. Petroleum is unique and s a complex mixture of thousands of compounds. Oil refinery workers are continuously exposed to numerous hazardous materials and working conditions that place them at continuous risk of injury and death.Petroleum contains the heavy metals as a natural constituent or as additives. The main threats to human health from heavy metals are associated with exposure to lead, cadmium, mercury and arsenic. Several carcinogenic metals such as arsenic, cobalt, chromium, lead, mercury, and nickel induce redox reactions in living systems. These metals induce the production of reactive oxygen species in both in vivo and in vitro systems. These radicals have rendered oxidative damage to deoxyribonucleic acid, proteins, and lipids. Secretory immunoglobulin A is the main immunoglobulin found in mucous secretions from the tear glands, salivary glands, mammary glands, the respiratory system, the genito - urinary tract, and the gastrointestinal tract.Aims of the study Assessment of the salivary levels of heavy metals among the workers of Al - Daura oil refinery, assessment of the oxidative status in the oral cavity of the workers by measurement of Malondialdehyde and Superoxide dismutase markers,assessment of the oral immunological activity by measurement of secretory immunoglobulin A level in saliva and Assessment of the oral findings among the workers.Subjects, Materials and Methods This study was done in Al - Daura oil refinery, samples consist of 60 workers involved in refining processes as study group subdivided into three subgroups which represent the different sections in the refinery and 20 subjects not involved in refining processes as control group. Oral examination and saliva collection was done to assess the oral findings and measure the level of heavy metals (lead and cadmium), oxidative status (Malondialdehyde and Superoxide dismutase) and secretory IgA.Results The mean of salivary lead and cadmium was higher in study group (6.34 ?g/dl and 0.56 ?g/l respectively) than that of control group (3.3?g/dl and 0.34 ?g/l respectively) with highly significant difference (p

اظهار بروتين p16 وفايروس الورم الحليمي البشري 81,81 ( في الحزاز المسطح الفموي وسرطان الفم الحرشفي

اسم المؤلف: صهيب راغب محسن
اسم المشرف: احلام حميد مجيد
الموضوع العام: طب الاسنان
السنة: 2015
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:

تاثير الكورتيزون المستنشق على الاطفال المصابين بالربو == The effects of inhaled corticosteroids on oral condition among asthmatic children

اسم المؤلف: مینة اسامة عبد الودود
اسم المشرف: زينب عبد الرضا الدهان
الموضوع العام: طب الاسنان
السنة: 2014
الموضوع الدقيق: طب اسنان الاطفال
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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