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Article
Prevalence of "White Spots" Around Orthodontic Brackets: A Clinical Study

Authors: Ahmad A Abdulmawjood --- Mahmood Kh Ahmed --- Ne’am R. Al- Saleem
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2012 Volume: 12 Issue: 2 Pages: 371-377
Publisher: Mosul University جامعة الموصل

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Abstract

Aim: To determine the prevalence of white spot lesions in orthodontic patients treated with fixed or-thodontic appliances at different treatment periods and to reveal the teeth most commonly affected by white spot lesions. Materials and Methods: Forty eight patients (31 females and 17 males) treated with fixed orthodontic appliance were included in this study. The patients were examined for the pres-ence of white spot before insertion of the appliance and after its removal using visual examination. Results: This study showed that there was a significant increase in the formation of white spot lesions along with the increase in treatment duration in male group, while females showed no significant dif-ference in white spots at different durations. The first molars were the most affected teeth by white spots followed by canines and second premolars. Conclusion: This clinical study showed that the teeth in buccal segment were affected by white spots more than incisors and the prevalence of white spots increased when the duration of treatment increased.


Article
Bond strength to etched and Re-etched enamel, dentin and dentino-enamel junction

Authors: Dr. Maha Adnan Habeeb. د.مها عدنان --- Dr. Angham Ghiyath Al-Hashimi B.D.S, M.Sc. د. انغام غياث
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2011 Volume: 8 Issue: 2 Pages: 100-105
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Etching and re-etching are frequently done technique to alter the tooth surface andmakes it more receptive to adhesion. This study was done to assess the effect of reetchingtechnique on bond strength to enamel, dentin and dentino-enamel junction.60 extracted human upper premolars teeth were collected cleaned, sectioned at thelevel of cervical line, embedded in acrylic block exposing certain grounded flatsurface of the crown and divided into 2 groups:Group A (30 etched specimens) etched with total etch (37% phosphoric acid)for 15 sec.Group B (30 re-etched specimens) etched and re-etched with total etch(37% phosphoric acid).Both groups were subdivided into:Subgroup 1 10 enamel specimensSubgroup 2 10 dentin specimensSubgroup 3 10 dentino-enamel junction specimensA standardized cylinders of light cure composite resin were bonded, and thespecimens were stored in deionized distilled water for 24 h. and testing was done withzwick test machine and statistically analyzed using analysis of variance test(ANOVA) and student t-test.The results showed non significant difference between all subgroups in groupA(etching group) and between all subgroups in group A Vs. group B subgroup 2(reetchedE), and showed a significant difference between all subgroups in group A Vsgroup B subgroup 3 (re- etched EDJ) and between group B sub1&2 (re-etched E & D)Vs group B sub 3 ( re-etched DEJ) ,furthermore there were a highly significantdifferences between all subgroups in group A Vs group B sub 2(re-etched D) andbetween group B sub 2(re-etched E) Vs groupB sub 2(re-etched D).Re-etching the enamel didn’t decrease the shear bond while re-etching dentinmarkedly decreased the bond strength. Further more re-etching the dentino-enameljunction lies in between.


Article
Prevalence of cervical enamel projections and enamel pearls on furcation area of Iraqi molar teeth

Author: *.Raed Aziz Badea B.D.S, M.Sc د. رائد عزيز بديع
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2005 Volume: 2 Issue: 2 Pages: 263-267
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Cervical enamel projections and enamel pearls in relation to molar furcationsmay act as predisposing factors in periodontal attachment loss. The objectives of thisstudy were to investigate the prevalence of cervical enamel projections and enamelpearls on furcation areas of molar teeth of Iraqi population. The material consisted of(465)extracted upper and lower molars. They were (200) upper molars and (200) )lower molars extracted because of` caries and pulp lesions(groupl), while the othermolars extracted because they were periodontally diseased(group2). The cervical )64(enamel projections were classified into three grades(described according to peter et al 2000)For group l the results showed that (5l%) of upper molars and (66%) of lowermolars had cervical enamel projections. Enamel pearls were identified on (1.5%) ofupper molars and (2.5%) of lower molars. Maxillary molars had (59.8%) grade Icervicaljnamel pro`ections and 28.4%) grade ll and (ll.7%) rade III. Whilemandibular molars showed (66.6%) teeth with grade I, (24.2%) teeth with grade IIand (9%) teeth with grade III .For grou 2 cervical enamel rojcctions were identifiedon (70.7%) ofthe collected molarsThe results of the present study give an indication that cervical enamelprojections are frequent enough to be of clinical importance


Article
Enamel defects and malocclusion in patients with celiac disease

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Abstract

Background: This study investigated the types and severity of enamel defects and malocclusion in celiac patients compared to matching controls.Materials and methods: One hundred and two celiac patients were included in the study they were attending the Gastroentrology and Hepatology Teaching Hospital.Results: Enamel defects in the study group showed a highly significant difference than found in the control group in bothdeciduous and permanent teeth. Concerning malocclusion study group, a higher percentage of severe anomalies (code 2)than control group the difference was statistically highly significant.


Article
The effect of the CO2 laser on the enamel cracks

Author: Dr. Muthenna Sh. Rajab. *
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2008 Volume: 5 Issue: 2 Pages: 148-153
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The objective of this study aimed to assess the effeats of the CO2 laser on the enamel cracks. The labial cracks of thirty extracted central incisors were irradiated with 4 Watts power and (0.4, 0.2 and 0.1) pulse durations. The laser used was CO2 laser with 10.6 μm in wavelength. The irradiated samples were sectioned into ground cross sections and examined under polarizing microscope. Enamel cracks can not be welded completely using CO2 laser irradiation. Although the formation of superficial glaze layer, there was a tendency to increase in the separation of the crack sides as the pulse duration of the laser increased

Keywords

Keywords: Enamel --- Crack --- CO2 --- Laser


Article
Evaluation of Enamel Coatings General Corrosion in Sulphuric Acid Solution at Different Temperatures
تقييم مقاومة طلاءات المينا للتأكل العام في محلول حامض الكبريتيك وبدرجات حرارية مختلفة

Authors: Ibtihal Abdul Razak --- Lamy'a M. Dawood
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2005 Volume: 24 Issue: 8 Pages: 1097-1106
Publisher: University of Technology الجامعة التكنولوجية

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Abstract


Article
Studying and Modeling the Effects of Quartz Addition and Heat Treatment on Mechanical Properties of Glass-Ceramic Coating
دراسة ونمذجة تأثيرات اضافة الكوارتز والمعاملة الحرارية على الخواص الميكانيكية لطلاء الزجاج السيراميكي

Authors: Ali H. Ataiwi --- Ibtihal A. Mahmood --- Jabbar H. mohmmed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2014 Volume: 32 Issue: 7 Part (A) Engineering Pages: 1811-1824
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this work, a new glass-ceramic coating has been developed and applied, as a single coat without prior chemical treatment of the surface, using the dipping technique on metal substrate. the coating are designed for application on varies grades of low alloy steel, the selected substrate was low carbon low alloyed steel with (0.2)%C. Various heat treatments at temperatures ( 500,550, and 600˚C ) at different times (60 & 120)min and with quartz addition in the range (0-15)% were used to obtain a glass-ceramics that have the optimum coating properties. These coating have been characterized by x-ray diffraction analyses and the results showed presence of a number of microcrystalline phases which are formed during the heat treatments. The results showed the suitability of this coating for protection the metal substrate which was used in present work. The results of tests also indicated that the mechanical properties ( hardness, adhesion strength, and thermal stability) of resultant coating were greatly improved by both addition of quartz into enamel frit and heat treatments for all cases, this is attributed to the formation of complex network from crystalline phases(Li2SiO3, Li2TiSiO5, NaAlSi2O6, and SiO2) which are the main phases in the resultant glass-ceramic coating. It has been found that the heat treatment at 600˚C for 120min with 15% quartz addition brought the optimum values for ( hardness, adhesion strength, and thermal stability) of resultant coating which are improved by (70.58%, 33.84%, and 39.68%) respectively. Mathematical modeling is implemented and regression equations are obtained using ( SPSS ) software to predict the experimental data for mechanical properties of resultant coating. Comparing the predicted and measured values gives high prediction accuracy. The accuracy of prediction has been (98%, 98.5%, and 97.4%) for ( hardness, adhesion strength, and thermal stability) respectively.

في هذا العمل تم تطوير طلاء سيراميكي جديد واستخدامه، كطبقة طلاء واحدة بدون معاملة كيميائية مسبقة للسطح، باستخدام طريقة التغطيس على المعدن الاساس. صمم الطلاء للاستخدام على الانواع المختلفة للفولاذ المنخفض السبك، المادة الاساس المختارة كانت فولاذ منخفض السبك منخفض الكاربون (0،2)% كاربون. تم استخدام معاملات حرارية مختلفة عند درجات حرارة (500، 550، 600) درجة مئوية وبازمان مختلفة(60، 120) دقيقة مع اضافات كوارتز بحدود (0-15)% للحصول على الخواص المثلى لطلاء السيراميك الزجاجي. تم توصيف هذه الطلاءات باستخدام تحليل حيود الاشعة السنية حيث اثبتت النتائج وجود عدد من الاطوار البلورية الدقيقة والتي تكونت خلال المعاملات الحرارية. بينت النتائج ملائمة هذا الطلاء لحماية المعدن الاساس المستخدم في هذا العمل. كذلك بينت نتائج الاختبارات ان الخواص الميكانيكية ( الصلادة، متانة الالتصاق، والاستقرارية الحرارية) للطلاءات الناتجة قد تحسنت بصورة كبيرة من خلال كلا من اضافة الكوارتز الى مادة الطلاء (الفرت) وكذلك من خلال المعاملة الحرارية وفي جميع الحالات. هذا التحسن مرتبط بتكون شبكة معقدة من الاطوار البلورية (Li2SiO3 Li2TiSiO5, NaAlSi2O6, and SiO2) والتي كانت الاطوار الرئيسية في طلاءات السيراميك الزجاجي الناتجة. وقد وجد ان المعاملة الحرارية عند (600) درجة مئوية واضافة (15)% كوارتز قد جاءت بالقيم المثلى ل (الصلادة، متانة الالتصاق، والاستقرارية الحرارية) للطلاء الناتج حيث تحسنت بنسبة (70،58%، 33،84%، و 39،68%) على التوالي. تم استخدام موديل رياضي والحصول على معادلات الانحدار باستخدام برنامج(SPSS) للتنبا بالبيانات العملية للخواص الميكانيكية للطلاء الناتج. اعطت المقارنة بين قيم النتائج المنتبئة والمقاسة دقة تنبأ عالية. حيث كانت دقة التنبأ (98%، 98،5%، و 97،4%) لخواص (الصلادة، متانة الالتصاق، والاستقرارية الحرارية )على التوالي.


Article
Effect of Some Medicines on Caries of Deciduous Teeth

Authors: Manar M. Mahmoud --- Saher S. Gasgoos
Journal: Journal of Oral and Dental Research مجلة طب الفم والاسنان ISSN: 23106417 Year: 2017 Volume: 4 Issue: 2 Pages: 52-61
Publisher: Iraqi Association for Oral Research الجمعية العراقية لبحوث طب الفم

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Abstract

Background Dental caries in addition known as tooth decay is a breakdown of teeth due to actions of bacteria. The cavities may be a number of dissimilar colors from yellow to black. Symptoms may contain pain and diffculty with eating. Aims To determine the direct effect of the oral medicines which were used for long time by children on the teeth. To reduce the negative effect of these drugs. Material and Methodsthe study used medications that are prescribed for children for long time that administrated only orally to determine the direct effect of these drugs. The study sample included lower deciduous molars, which were obtained from children who required extraction of their mobile molars after taking the agreement of parents. Sample size was (50) freshly extracted, caries-free lower molar of patients aged 10-12 years old. Teeth were divided into fve groups with 10 samples in each group, natural saliva was collected from a number of children and was added to the solution to simulate the oral cavity. The incubation period was 32 days then sectioning the samples and measure the lesion depth by polarized microscope. Results Verapamil produced maximum lesion depth in enamel while Dexamethasone was associated with minimum lesion depth. Conclusion it is obvious that all test medications affect the enamel of tooth by different degree.

Keywords

deciduous teeth --- enamel --- caries --- medications


Article
Enamel Hypoplasia among Tikrit City School Children Aged 6 Years to 13 Years Old

Author: Azhar A. Hussien ازهار عماش حسين
Journal: Tikrit Journal for Dental Sciences مجلة تكريت لعلوم طب الاسنان ISSN: 20731213 Year: 2017 Volume: 5 Issue: 1 Pages: 115-120
Publisher: Tikrit University جامعة تكريت

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Abstract

Enamel hypoplasia: its deficiency could be occurring when the enamel of the tooth does notform completely; this is may be due to many diseases or malnutrition. Enamel hypoplasiacould be appear as horizontal lines or chain of grooves or pits over the outer surface of thetooth. The purpose of this current study was to find out the prevalence of enamel hypoplasiafor the permanent and deciduous teeth in primary school children in Tikrit city, becausechildren with enamel hypoplasia can suffer from cosmetic issues, tooth sensitivity andincreased risk of dental caries. This current study is cross-sectional study was conductedthrough a clinical examination of teeth among 720 children of age rang (6 to 13) yearsenrolled in primary public schools of Tikrit city; they were accepted to participate in studyafter the aim of study was explained. The prevalence of enamel hypoplasia was studied inrelation to age and gender. Diagnosis of enamel hypoplasia takes place by well traineddentist. The prevalence of enamel hypoplasia was founded to (6.2%); boys more affectedthan girls with odds ratio 1.03 and there was no statistically significant differences. Theanterior teeth were the most affected teeth with enamel hypoplasia specially the upperpermanent central incisor (2.9%). Developmental enamel hypoplasia has a high level ofimportance because of being predictors of dental caries. Children suffered from enamelhypoplasia require a preventive intervention as a priority and early treatment.


Article
Evaluation of enamel surface damage after debonding using three different pliers "An in vitro study"

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Abstract

AbstractThis study aims to compare the effectiveness of three different pliers in debondingstainless steel and ceramic brackets, also to evaluate enamel surface damage and thesite of bond failure after debonding.Sixty premolars, extracted for orthodontic purposes, were divided into 3 groups of20. The enamel surfaces were examined with 10X magnifying lens. Two types ofbracket (stainless steel and ceramic) was bonded and debonded in each group using:conventional debonding pliers, bracket removal pliers, and ligature wire cutter. Afterdebonding, the enamel surfaces were inspected under a stereomicroscope to determinethe predominant site of bond failure. Then stereomicroscope was used to evaluateenamel surface damage after the removal of residual adhesive.The enamel surface damage showed a statistically significant difference in ceramicbracket groups, whereas, it was statistically insignificant in stainless steel bracketgroups. The amount of the adhesive remained on the tooth surface was statisticallyinsignificant in both stainless steel and ceramic bracket groups. The predominantfailure site was within the adhesive itself for both types of brackets.The enamel surface damage that results from debonding of ceramic brackets washigher than that found with the stainless steel brackets especially with the use ofbracket removal pliers "used in this study"

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