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Article
Orthodontic Treatment and Temporomandibular Joint Condylar Position Relationship with Disk Displacement (Magnetic Resonance Imaging Study)

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Abstract

Temporomandibular joint (TMJ) is a complex synovial articulation between the mandibular condyle and the glenoid fossa of temporal bone. The question of whether a relationship exists between orthodontic treatment, abnormal condyle and disk position, and temporomandibular disorders has been investigated for many years. Despite the abundance of studies, the question continues to trouble orthodontists.This study conducted to assess the relationship between orthodontic treatments, abnormal condyle and disk position, with temporomandibular disorders, and to study the disk- condyle relationship in term of presence or absence of anterior disk displacement. By mean of Magnetic Resonance Imaging a cross sectional investigation for the condyles of temporomandibular joints (TMJs) and disk position was conducted to 50 TMJs of 25 patients between 19-30 years of age who had undergone orthodontic treatment (by upper and lower fixed orthodontic appliances with extraction of maxillary first premolar only for treatment of class II division 1 malocclusion), and 50 TMJs of 25 patients who had not yet received orthodontic treatment from the same class and matched age group.The results of this study showed that 30% of pre-treatment group have anterior disk displacement in comparison to 26.0% of the post treatment group. The condyle position is more concentric in post treatment group than pre-treatment, and the position of the disk is not affected by orthodontic treatment. This conclude that condyle position of the TMJ may be affected by orthodontic treatment, but the disk position is not.


Article
Pattern of Maxillo-Facial Fractures and Their Management in Iraqi Kurdistan Province

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Abstract

Forty three in-patients with Maxillo-facial fractures admitted to Rizgaree hospital in Arbil in the period from May 2007 to April 2008. Thirty seven males were affected and only 6 females were involved with a ratio of male: female ratio of 6.2 : 1.65 % of the patients belonged to 16 – 35 years age group .People with small businesses were the mostly affected group 39.5% . They mostly attended between June and August and on Saturday and Sundays and Wed8) Maxillofacial fractures sites related to gunshots.Figure 8 show the distribution of site of Maxillofacial fractures resulting from gunshots. There were only 4 patients involved in gunshots Maxillofacial fractures all of them were males . There were 10 fractures.Maxilla was mostly involved (40%) followed by zygoma (20%) and body of mandible (20%). One of the victims have lost a right eye .Fighting or assaults –involved only 2 patients, both were male and they had 2 zygomatic fractures on the left side..The most common cause of facial injures were falls and road traffic accidents followed by gunshots and fighting .The most common site of facial fractures in road accidents and assaults were left zygoma and maxilla (> 65 %) while with falls they were nearly equal ( 37.7 % and 31.1%) .Most of the cases were treated conservatively, and most of the surgical intervention was localized in zygomas with Gillies approach as the most common surgery (24.2%) performed.Occiptomented view was the most common X-ray taken (34.4%) because the majority of trauma was localized in the middle third.


Article
Pleomorphic adenoma of the salivary glands: a retrospective study of 40 cases.

Author: Dr. Adil H. Shebeeb. B.D.S.,M.Sc. * د. عادل حيدر
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2008 Volume: 5 Issue: 3 Pages: 319-323
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Forty cases of pleomorphic adenoma( PA) presented in this study were diagnosed in the department of the Oral Pathology, College of Dentistry , Baghdad University covering the period 1982-1992. The tumours were distributed according to age, gender and site of occurrence. Patients ranged in age from 11 to 80 years. The age group 41-50 years was most frequently affected by PA 12 cases (30%) followed by 3rd and 4th decades 9(22.5%) 7(17.5%), respectively .It is evident in this study that PA was more frequently seen in females 24 (60%) than males16 (40%).It was observed from results that the palate was the most common site for occurrence of PA 32(80%), followed by the parotid gland 3(7.5%). Most of the results were comparable to the data of the literatures.


Article
Effect of Siwak Extract on the Microhardness and Microscopic Feature of Initial Caries-Like Lesion of Permanent Teeth, Compared to Fluoridated Agents

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Abstract

Siwak is a chewing stick used to clean the teeth and message the gum. Their routine use was shown to be associated with the reduction in severity of dental caries. This study aimed to test the effect of water Siwak extract on the microhardness and microscopic features of artificially initiated carious lesion of the outer enamel surface, in comparison to stannous fluoride and sodium fluoride. Upper first premolars were extracted and subjected to pH cycling procedure. Teeth immerged individually in 20 ml of selected agents for four minutes then rinsed by de ionized water. Agents involved were 5% and 10% water Siwak extract, 8% stannous fluoride and 0.05% sodium fluoride. Samples were subjected to Vickers microhardness test and microscopic examination before and after the pH cycling and following insertion in the agents. Water Siwak extract, stannous fluoride and sodium fluoride were found to increase the microhardness values of de mineralized enamel surfaces, this were statistically highly significant for Siwak extract and stannous fluoride (P< 0.01) and significant for sodium fluoride. However none of the mentioned agents was able to increase the micro hardness to approximate the original values of the sound enamel. Under polarized light results revealed that water Siwak extracts and stannous fluoride produce the best remineralization surface zone. Water Siwak extracts is very effective in remineralization of initial carious lesion.


Article
The Use of Computer Technology in Dental Arch Crowding Assessment

Author: Dr. Mehdi Abdul Hadi Al-Rubayee. B.D.S MSc * د. مهدي عبد الهادي
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2008 Volume: 5 Issue: 4 Pages: 372-383
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Background: Correct alignment of teeth is a fundamental goal of Orthodontic treatment. The accurate assessment of dental crowding and the space required to alleviate it, is critical for correct orthodontic diagnosis and treatment planning.Objectives: To assess dental crowding by using two different methods, which are manual and computerized in order to compare the advantages and disadvantages of both methods.Methods: In this cross –sectional study, we studied a convenient sample of 100 individuals (50 male and 50 female) with different degrees of crowding. Upper and lower dental casts were obtained for each subject and these casts were analyzed by using two methods, manual and computerized.Results: It was found that there is a significant difference between the manual and the computerized method in all measurements (crowding, space available and space required). Also, it was found that the computerized method is a quick method and more practical for the storage of a large number of dental casts and more reliable for the measurement of the space available than the manual method. But, there was some difficulty in the assessment of severely crowded groups (>4mm).Conclusions: The degree of dental crowding increased when the teeth size increased and arch perimeter decreased. The degree of crowding in the upper arch is more affected by the size of the teeth rather than the size of the arch, while the degree of crowding in the lower arch is more affected by the arch size rather than teeth size.


Article
Salivary gland mucoceles: A clinical study of 103 cases

Authors: Dr.Ali S. Muhsin B.D.S., M.Sc. Oral Pathology ** د.علي سامي --- Dr.Adil H. Shebeeb B.D.S., M.Sc. Oral Pathology* د. عادل شبيب
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2008 Volume: 5 Issue: 4 Pages: 418-421
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Mucocele is a tissue swelling composed of pooled mucus that escaped into the connective tissue from a severed salivary excretory duct (extravasated).In the present study 103 cases of mucoceles reviewed from the records of patients at the Department of the Oral Pathology, faculty of Dentistry , Baghdad University over 11 years period ( 1982-1992). Mucoceles were statically analyzed according to age, gender , site of occurrence and type.It was found that a greater number of mucoceles cases 37(36%) occur in patients at 2nd decade of age followed by 29(28.2) of cases occurred in 3rd decade of age. Mucoceles were occurred more in males than females 57(55.2%) ,46 (44.8%),respectively.Lower lip was the predominant site for occurrence of mucocele 84(81.6%) followed by the floor of the mouth 12(11.7%).The most frequent type of mucocele was of extravasated type100(97.1%) whereas it was only 3(2.9%)for mucous retention type.


Article
“Effect Of Surface Treatments On The Adhesive Wear Of Low Carbon Steel”
تأثير المعالجات السطحية على البِلى الالتصاقي لصلب منخفض الكربون"

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Abstract

AbstractWear is one of the problems that occur in the moving parts either by rolling or sliding. This work includes experimental study on the wear of low carbon steel. Three surface treatments were chosen these are cyaniding, solid carburizing and hard chrome plating. The wear test was made under dry contact condition for the treated and the untreated surfaces. A constant load and speed were used for two types of motion: sliding-rolling and pure rolling. An Amsler machine was used. The high carbon steel was chosen for making the upper specimen and the low carbon steel was chosen for making the lower specimen. The high carbon steel was hardened while the other was surface treated (carburizing, cyaniding). The hard chrome plating was also used to increase the surface hardness. It was noticed that increasing of surface hardness reduced the wear amount produced, and the cyaniding gave the highest resistance to wear whereas the hard chrome plating gave the lowest one, and the wear under pure rolling condition was small .It was found that the wear rate of treated surfaces is high in the first stage of the test then the rate decreases until it reaches a steady state and for both motions.Key Words: Wear, surfaceو treatment, hardening, steel.

الخلاصة البِلى واحد من ألمشاكل التي تحصل في الأجزاء المتحركة سواء المتدحرجة أو المنزلقة. يتضمن البحث دراسة عملية لظاهرة البِلى التي تحصل في الصلب المنخفض الكربون والذي يستخدم لمطيليته الكبيرة ومقاومته للصدمات وكونه من المعادن الرخيصة الثمن، ولأجل تقليل مقدار البِلى في السطح ينبغي إجراء معالجات سطحية عليه وقد اختيرت ثلاثة معالجات سطحية وهي الكربنة والسيندة والطلاء بالكروم الصلد.أجريت فحوصات البِلى الجاف(بدون تزييت) للسطوح المعالجة وغير المعالجة وتحت حمل وسرعة ثابتين وبأختيار اسلوبين من الحركة: تدحرج-انزلاق وتدحرج تام. استخدمت ماكنة الفحص امسلر لهذا الغرض واختير الصلب العالي الكربون لتصنيع النموذج العلوي للفحص واختير الصلب المنخفض الكربون لتصنيع النموذج السفلي للفحص .عومل الصلب العالي الكربون حرارياً حيث تم تصليده أما الصلب المنخفض الكربون فعولج سطحياً حيث أجريت الكربنة الصلبة والسيندة وكذلك الطلاء بالكروم الصلد وذلك لزيادة صلادة السطح. لوحظ أن زيادة الصلادة السطحية بالطرق الثلاثة قد قلل من مقدار البِلى الحاصل، وأن السيندة أبدت مقاومة اكبر للبِلى بينما أبدى الطلاء بالكروم اقل مقاومة وتبين أن البِلى في حالة التدحرج التام يكون قليلاً ووجد أيضا أن معدل البِلى للسطوح المعالجة يزداد زيادة كبيرة خلال مراحل الفحص الأولى ثم يقل حتى يصل إلى حالة مستقرة ولكلا نوعي الحركة.


Article
Estimation of Design Parameters for Cellular WCDMA Network
تقدير معالم التصميم لشبكة اتصالات خلوية نوع WCDMA

Author: S. A. Mawjoud سامي عبد الموجود
Journal: AL Rafdain Engineering Journal مجلة هندسة الرافدين ISSN: 18130526 Year: 2008 Volume: 16 Issue: 4 Pages: 59-68
Publisher: Mosul University جامعة الموصل

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Abstract

AbstractThe estimation of design parameters for WCDMA network which support different data rate (Multimedia) services is an essential step in network planning. The estimated parameters includes: Cell coverage range using path loss propagation model, average and maximum path loss, throughput, capacity / km2, number of users per cells blocking capacity, tracking efficiency. The parameters are computed for different data rates.Key words: WCDMA, noise rise, load factors.

إن تقدير معالم التصميم لنظم WCDM هي من الأولويات لتصميم شبكة قادرة على نقل بيانات مختلفة المعدل تمثل الصوت أو الصورة. وتشمل المعالم ( مدى تغطية الخلية باستخدام نموذج فقد المسار المناسب ، معدل فقد المسار وأقصى فقد للمسار ، الإخراج ، السعة لكل كيلومتر مربع ، عدد المستخدمين في الخلية ، سعة الصد ، وكفاءة النقل الرئيسي البعيد.


Article
The effect of additives on the linear thermal expansion of Phosphate-bonded investment

Authors: Dr. Mohammed K. Gholam, B.D.S., M.Sc.** د.محمد قيس --- Dr. Ammar A. Alsa'ady, B. D.S., M.Sc., Ph. D.* د. عامر السعدي
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2008 Volume: 5 Issue: 1 Pages: 7-13
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

One of the main considerations of the investment materials is there adequacy to expand thermally and by setting expansion to compensate for casting shrinkage, and any investment having zero setting expansion and adequate thermal expansion, by the use chemical additives and water instead of colloidal silica suspension would eliminate all inaccuracies arises from distortion of the wax pattern due to setting expansion.Thus the aim of this study was to evaluate the influence of two alkaline metals as additives K2SiO3 and Na2SiO3, to enhance the thermal expansion of phosphate – bonded investment without the use of colloidal silica suspension.Three mixtures (45 samples) were prepared, mixture I of 15 samples contains Na2SiO3, Mixture II of 15 samples contains K2SiO3 in percentages of (0.5, 1.0, 1.5, 2.0, and 2.5) for each three samples of both (mixture I & II), and mixture III of fifteen samples as a control group without additives. The thermal expansion measured by vitreous silica dilatometer from 100 – 950 ºC.The results showed that the highest mean of thermal expansion was in samples that contain Na2SiO3, and the lowest mean of thermal expansion was in the control group samples.


Article
Root trunk height of maxillary and mandibular permanent first molars in Iraqis (a pilot study)

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Abstract

Although the Root Trunk Height (RTH) as a variable in different racial groups was extensively studied, but its relation to the presence and absence of other anatomical abnormalities as Cervical Enamel Projection (CEP) never been tested. On the other hand, data focused on this variable in our community are not available. So the aim of this pilot study is to provide a base line data on this important anatomical variable (RTH) in our community and to calculate its possible correlation to the presence of (CEP). In this study (242) extracted permanent molars (126 maxillary first molar and 116 mandibular first molar) were collected from the dental clinics of Al-Mustansiriya teaching hospital /college of dentistry. RTH for each tooth was measured and presence of CEP was recorded. Results of this research showed that that mean values of RTH of permanent first molars in Iraqis were comparable with that found in other countries. On the other hand, there is a highly significant relation between the RTH and presence of CEP on buccal and mesial aspects of maxillary first molar and buccal aspect of mandibular first molar, while this relation is not significant on distal aspect of maxillary first molar and lingual aspect of mandibular first molar.

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