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Article
Prevalence of overhang margins in posterior amalgam restorations and alveolar bone resorption

Authors: Adel F. Ibraheem عادل فرحان ابراهيم --- Khulod A. Al-Safi خلود الصافي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2005 Volume: 17 Issue: 1 Pages: 11-13
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Overhanging dental restorations(ODR) are a major dental health problem, it is an etiologic factor in the progression of periodontal disease, and are alarmingly prevalent .The purpose of this study was to determine the prevalence of overhang margins and associated periodontal status in 100 patients, clinically detectable overhang margins were recorded on posterior teeth.Materials and Methods: Overhanging margins on a proximal restoration were detected by using of bitewing radiographs. 2089 restored surfaces were evaluated, of these 1185 had overhanging margins.Results: As far as related to their effect (ODR) on periodontal health, significantly more bone loss-attachment occurs adjacent to ODR compared to teeth without ODR.Conclusion: This study show high prevalence of overhanging amalgam margins, further more, this study show that ODRs have a significant influence on periodontal status.

Keywords

Overhang --- amalgam --- bone resorption


Article
Negative Effect of Laser Treatment with Nd:YAG on the Corrosion of Amalgam in Artificial Saliva
التأثير السلبي للمعاملة الليزرية بليزر Nd:YAG على تأكل الحشوة الزئبقية في اللعاب الاصطناعي

Author: Lec. Fatima I.Sultan
Journal: journal of the college of basic education مجلة كلية التربية الاساسية ISSN: 18157467(print) 27068536(online) Year: 2013 Volume: 19 Issue: 79 / علمي Pages: 863-873
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

This work involves study the corrosion behavior of amalgam in artificial saliva at pH=6 and 37oC after using Nd: YAG, where this laser used for healing the cancer. This study indicates that laser surface treatment affecting corrosion resistance of amalgam, and the results indicate that the laser treatment don`t give the desired purpose because the nature of amalgam and the presence of mercury in this alloy which may be evaporate and it give toxicity for human and the energy of treatment must be low to avoid evaporation. In this work, laser treatment with two pulses under experimental conditions gave little improvement in corrosion resistance of amalgam compared with one and three pulses through the corrosion parameters of polarization behavior.

يهدف هذا البحث الى دراسة سلوك التأكل للحشوة الزئبقية بعد المعاملة الليزرية بليزر Nd:YAG في اللعاب الصناعي عند اس هيدروجيني 6 ودرجة حرارة 37 درجة مئوية حيث يستخدم هذا الليزر لمعالجة الاورام في اللثة. ان الدراسة الحالية اثبتت بان المعاملة الليزرية تؤثر على مقاومة التأكل بسبب طبيعة الحشوة الزئبقية الحاوية على الزئبق والذي قد يتبخر معطياً تأثيراً سمي وان الطاقة الليزرية يجب ان تكون اقل ما يمكن. ان المعاملة الليزرية في هذا البحث بضربتين ليزريتين اعطت تحسناً قليلاً في مقاومة التأكل مقارنة مع المعاملة الليزرية نبضة واحدة وثلاث نبضات كما تبينه متغيرات التأكل المقاسة من سلوك الاستقطاب.

Keywords

Amalgam --- Laser treatment --- Corrosion


Article
Fracture resistance of premolars with bonded amalgam restorations

Authors: Abdul–Haq A Suleiman --- Mohammad Gh Hamdoon
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2003 Volume: 3 Issue: 2 Pages: 156-160
Publisher: Mosul University جامعة الموصل

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Abstract

The aim of this in vitro study is to evaluate the fracture resistance of premolars with three surface amalgam restorations. Fifty premolars were used, and divided into five groups. The teeth in group one remains intact whereas the teeth in the second group prepared and not restored. The teeth in the third group prepared and restored with amalgam only. In groups four and five, the amalgam restorations were lined with All–Bond 2 and Scotchbond Multi Purpose Plus respectively. After thermocycling, the teeth were tested under universal compression machine at a crosshead speed 5 mm/minute. Data were analyzed using one way Analysis of Variance and Duncan’s Multiple Range Test. The results of this study indicates that both Scotchbond Multi Purpose Plus and All–Bond 2 increase the fracture resistance as compared to the control groups (groups two and three). The results of this study also show no significant difference between the two bonding agents regarding teeth fracture resistance.


Article
Assessment of rabbit mandibular bone response to different amalgam implants radiographically

Authors: Nazar Gh Jameel --- Mohammad S Suleiman --- Ragheed M Basheer
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2004 Volume: 4 Issue: 3 Pages: 20-27
Publisher: Mosul University جامعة الموصل

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Abstract

The radiograghical interpretations can give an excellent indication about the biological response of hard tissue like bone to different foreign materials imp-lanted within it. This clinical study was carried out to evaluate radiographically the bone reaction of four different types of Iraqi manufactured amalgam alloys (in addition to Degussa alloys as a positive control) implanted within holes prepared in the mandibular bone of the rabbit, and additional negative control group in which the hole remained empty without any implanted materials was also included. The evaluation was done by careful verification of the presence or absence of the radiolucency at the periphery of the implanted amalgam at three different time intervals, the response varied from radio-lucency to radioopacity depending on the reaction of bone to different implanted amalgam alloys. Accordingly, the biocompatibility of the amalgam alloy was deter-mined depending on the radiographic pic-ture of bone response at the margin of the implanted alloys. The results showed no significant difference in bone response among the different types of alloy used.

Keywords

Amalgam --- bone --- implant --- biocompatibility


Article
An evaluation of the Effect of Surface Treatment On Amalgam Repair

Authors: Dr. Abdul Karim J. Al-Azzawi, B.D.S., M.Sc. د. عبد الكريم العزاوي --- Dr.Baidaa M. Zaidan, B.D.S., M.Sc. Prof. د. بيداء زيدان
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2008 Volume: 5 Issue: 4 Pages: 341-347
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The purpose of this in vitro study was to evaluate the effect of different surface treatments on shear bond strength of repaired amalgam using two types of amalgam. 120 acrylic blocks (2.7cm diameter by 2.0cm high) were constructed from cold cure resin, each one contained cylindrical hole (7mm diameter by 2mm high) on its circular face that filled with amalgam. The samples were divided into immediate repair group and delayed repair group, which was stored and incubated at 37C0 for one month. After aging the amalgam surface of delayed repair was finished with carbide bur and polished with abrasive rubber cup then divided into three groups according to the surface treatment that include group with out surface treatment, group roughened with diamond bur and the last group was abraded with aluminum oxide (50m) particles size, both immediate and delayed repair were further subdivided according to the type of amalgam used into three subgroups. The repair procedure was done by using a Teflon split mold which containing an opening (3mm diameter by 5mm high) then all the samples were storage and incubated at 37C0 for one week prior to testing.Testing was done by applying shear force at the interface between the initial and repair amalgam with special designed chisel shape rod by using Zwick testing machine at across head speed of 5mm/min.Analysis of the results showed that the shear bond strength in immediate repair were significant higher than of delayed repair and the group roughened with diamond bur is higher than group treated with aluminum oxide and untreated group.The shear bond strength of delayed repair of amalgam is less than that of immediate repair, the surface produced by roughening the samples with a diamond bur will give best strength than the surface treated by aluminum oxide and untreated surface (smooth surface) and the same types of amalgam restorations used in amalgam repair gave better result than different type of amalgam.


Article
Experimental Study and Mathematical Modeling for Corrosion of Amalgam at Different Periods

Authors: Hind B. Al-Atrakchy --- Khawla Abdul kathem --- Rana A. Majed --- Hawraa D. Al-Deen
Journal: Tikrit Journal for Dental Sciences مجلة تكريت لعلوم طب الاسنان ISSN: 20731213 Year: 2014 Volume: 3 Issue: 1 Pages: 30-37
Publisher: Tikrit University جامعة تكريت

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Abstract

This work involves experimental study for corrosion of amalgam as filling material after different period time (0, 7, 14, 21, 35, 42 days) in artificial saliva by electrochemical method to estimate corrosion parameters such as corrosion potential Ecorr, corrosion current density icorr, and Tafel slopes bc & ba. The results of polarization resistance which calculated according to Stern- Geary equation indicates that the resistance of amalgam was increased during the experimental period due to stable phases which produced between mercury and other powders in amalgam such as Sn–Hg and Ag–Hg, in addition to Ag–Cu and Ag–Sn phases. Cyclic polarization test shows that the reverse scan curves meet the forward scan curve along the passive range.Numerical modeling was achieved to estimate the corrosion behavior of amalgam in artificial saliva through longer period time, the results of this modeling shows that values of polarization resistance for amalgam at long time of filling decreases with time, but after 2200 days of filling, i.e. after at least 6 years.


Article
The effect of amalgam alloy types, surface treatments, and bonding agents on the shear bond strength between amalgam and resin composite

Authors: Raghad A. Rasheed --- Abdul–Haq A. Suliman
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2006 Volume: 6 Issue: SpIss Pages: S38-S47
Publisher: Mosul University جامعة الموصل

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Abstract

To evaluate the effect of amalgam alloy types, surface treatments, bonding agents, on the shear bond strength between set amalgam and resin composite restorative materials. Materials and Methods: Three hundred and thirty eight holes (6 mm in diameter and 2 mm depth) prepared in a 2x2.5 cm cold cure acrylic resin blocks in which amalgam was condensed. The 338 samples were divided into two groups, the control group which consisted of 26 intact amalgam samples, and the repair group consisted of 312 repair amalgam samples. Each group (intact, and repair) was subdivided into two groups according to the type of amalgam alloy. Half of the samples were filled with spherical amalgam alloy and the other were filled with admixed amalgam alloy. The repair samples then divided in to four groups according to the surface treatment, in turn each sub-group divided into three groups according to the bonding agent. The samples were thermocycled, before shear bond strength was tested. The mode of failure was observed for each specimen. Results and Conclusion: The statistical analysis showed that the repair strength was 50% of the intact strength, and the admixed amalgam samples showed higher shear bond strength than spherical amalgam samples. The group roughened with diamond bur showed higher repair bond strength than the groups received other surface treatment. The use of dentin bonding agent (All–Bond 2 and Alloybond) would increase the repair bond strength between the amalgam and the composite restorative materials. And the mode of failure was mostly an adhesive type.


Article
Measurement of Mercury Concentration in Saliva of Selected Sample of Children in relation to Amalgam Fillings

Authors: Abdul Wahab T. Shakir عبد الوهاب شاكر --- Ban Ali Salih بان علي صالح
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2011 Volume: 23 Issue: special issue Pages: 134-140
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Dental amalgam fillings interact in a complex way with the environment in the oral cavity as they aresubjected to chemical, biological, mechanical, and thermal forces. These forces change the restoration’sappearance and properties, causing metal ions, amalgam debris, non-metallic corrosion products, and mercuryreleased into the oral cavity. The aims of this study were Measure the concentration of mercury in saliva of children inrelation to the number of amalgam fillings before and after chewing and measure the continuous release of mercuryvapor from amalgam fillings in children and its relation to gender and age.Materials and methods: The sample consists of 51 children between 8-10 years of age and they were divided intothree groups according to the number of amalgam fillings they have in their teeth (1st group children didn't haveamalgam fillings in their teeth, 2nd group children had 1-2 amalgam fillings, 3rd group children had ≥3 amalgamfillings). Then saliva samples were collected from each child before and after chewing of sugar free chewing gum insterilized disposable cups.Results: The results indicated that minute amount of mercury were continuously released from amalgam restorationsand the release is accelerated after stimulation (chewing).Also the results demonstrated a positive correlationbetween the number of amalgam fillings and mercury concentration in saliva, mercury in saliva of children whodidn't have amalgam fillings in their teeth may come from other sources such as air, water and food. There was norelation between mercury concentration in saliva of children and the gender and age of children

Keywords

children --- mercury --- saliva --- amalgam filling


Article
The evaluation of amalgam and composite restorations in Mosul private clinics

Author: Moataz Gh Al–Shaekh Ali
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2004 Volume: 4 Issue: 4 Pages: 113-118
Publisher: Mosul University جامعة الموصل

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Abstract

The aim of this study was to evaluate amalgam and composite resin restorations work in private practice in Mosul City. A list of dentist practicing in private clinics was obtained from the Iraqi Dental Association in Mosul City. One hundred sixty dentists involved in the questionnaire were selected randomly from a total of 200 dentists in the list supplied. The questionnaire concerned with the step–by–step restorative treatment including diagnosis and case selection, cavity preparation, types of liners and bases used, amalgam restoration and direct esthetic restorations. The results revealed that 100% of the respondents perform restorative dental therapy in their private clinics. The results also revealed an evaluation (as percentage) for most of steps concerned with direct restorative techniques.


Article
Effect of in-dental clinic bleaching agents on the releases of mercury from the specimen of amalgam restoration in relation to their times intervals

Authors: Afnan AL-Shimmer افنان الشمر --- Mohammad Al-Casey محمد القيسي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: 1 Pages: 82-84
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Measuring the effect of bleaching agents on mercury release from dental amalgam is important fromboth restorative and toxicological points view. The aims of the study was to evaluate the effects of two differenttypes of bleaching agents for vital teeth by using with light source on the release of mercury from the specimen ofamalgam restoration .Materials and methods: Fifty three specimen of amalgam restoration, were subject to treated with bleaching agents( 35% hydrogen peroxide and carbamide peroxide ) and then application of light and laser radiation to activate thebleaching agents. Flameless atomic absorption spectrophotometer with Gold Vapor Generator was used tomeasure the release of mercury from the specimen of amalgam restoration.Results: Highly significant increase in the release of release of mercury from the specimen of amalgam restoration inrelation to the times intervals.Conclusions: In this study showed that release of release of mercury from the specimen of amalgam restoration,after treated with both 35% carbamide peroxide and 35% hydrogen peroxide increase with increase the time andcompared with control groups.

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