فهرست مطالب

Journal of Islamic Dental Association of IRAN
Volume:18 Issue: 2, 2006

132 صفحه، بهای روی جلد: 10,000ريال
تاریخ انتشار: 1385/08/25
تعداد عناوین: 16

فارسی
English

انتخاب همه

Microtensile bond strength of clearfil SE bond to caries-affected dentin and normal dentin

Amir Ghasemi, Majid Bargrizan, Mina Mahmoodi Page 8

Background And Aim
Bonding systems have been traditionally used on normal dentin, even though caries-affected and sclerotic dentin are often the clinically relevant bonding substrates. A self-etching primer adhesive system (Clearfil SE Bond) was evaluated for its ability to bond to caries-affected and normal dentin.
Materials And Methods
In this experimental study, twelve extracted human primary molars with occlusal caries were selected. The enamel and superficial dentin were ground with a diamond disk and stained with a caries detector solution (propylen glycol and 1% acid red). The red-stained soft dentin which was classified as infected dentin was excavated and the affected dentin and surrounding normal dentin were polished with a 600 grit silicon carbide paper under running water to achieve a flat surface. The entire flat surface was bonded with Clearfil SE Bond (Kuraray) according to the manufacturer’s instructions and covered with composite resin Clearfil AP-X (Kuraray) to form a composite crown, approximately 4.5 mm high. The teeth were stored in distilled water at room temprature for 24 hours and were then sectioned with a diamond saw under running water in both X and Y directions, perpendicular to the bonded surface with dimensions of approximately 0.8-1 mm, so that the bonded areas of the affected or normal dentin were isolated. The obtained rods were divided into two groups: Affected and sound dentin. After measuring the cross-sectional areas at the interface, the specimens were mounted in a microtensile tester machine and pulled under tension to failure. The mode of failure was evaluated using a streomicroscope and the data were analyzed by t-test.
Results
Statistical analysis indicated that the microtensile bond strength in affected dentin (21.53±6.52 MPa) was significantly lower (p<0.05) than normal dentin (26.98±7.31 MPa).
Conclusion
The studied self-etch system, attained lower microtensile bond strength in affected dentin as compared to normal dentin.

Abstract View Paper Original: Persian
Factors contributing to the incompatibility between new adhesive systems and various composite resin restorations

Fatemeh Maleknejad, Horiyeh Moosavi Page 15

Background And Aim
Although light cured composites are easily accessible, self/dual-cure cements and composite resins also have broad clinical applications. The aim of this study was to evaluate the incompatibility between new adhesives and different types of cement and composite resin restorations and their effects on interface bond strength.
Materials And Methods
All articles and theses on adhesives and cement/composite resin restorations up to June 2005, available at Mashhad dental school library, medline and other internet information banks were collected and evaluated.
Conclusion
Some two–step-total-etch and one–step-self–etch adhesives were incompatible with self/dual–cured cements and composite resins. This is due to the large concentration of acidic, ionic and hydrophilic resin monomers that result in adverse chemical interactions and increased permeability of these adhesives. In order to prevent the adverse acid-base chemical interactions between simplified adhesives, light cured cements or composites or dual cured adhesives containing catalysts should be used. For neutralizing the permeability effect of simplified adhesives, light cured composites or a single layer of unfilled resin bonding or flowable composites should be applied over the adhesive layer to induce rapid curing.

Abstract View Paper Original: Persian
A comparison of the accuracy and dimensional stability between two silicon impression materials (Speedex and Irasil)

Mahmood Sabouhi, Mansoor Dakhilalian, Navid Nehchir Page 22

Background And Aim
Condensation silicons are more commonly used in fixed Prosthodontics than other elastomers. The aim of this study was to compare the accuracy and dimensional stability of two condensation silicons: Speedex and Irasil.
Materials And Methods
A metal master model containing two abutments representing two prepared teeth with definite dimensions was prepared and a metal tray was made. 40 impressions were taken (20 of each impression material) and 10 of them were poured with die stone (Prevest) after 30 minutes and the other 10 were poured after 120 minutes, according to the manufacturer’s instructions. Using a steriomicroscope M6c-10 and Digital camera moticam-480 the following dimensions were measured three times on the metal and stone models: (1) x = distance between the center of the abutments (2) y1 = height of the abutment with an undercut (3) y2 = height of the abutment without an undercut (4) z1= width of the abutment with an undercut, and (5) z2 = width of the abutment without an undercut. The difference between the dimensions of the main and stone models was assessed.
Results
Multivariance and T-tests were used for statistical analysis. There was no significant difference in dimensional stability between groups 1 and 4 (Speedex, 30' and Speedex, 120') and between groups 2 and 3 (Irasil, 30'-120'). A significant difference was observed between Speedex and Irasil in both time periods (30 and 120 minutes). The difference between the die stone and the master model was significant in mesiodistal (x) and buccolingual (z1) dimensions for both materials. A significant difference was also found between Irasil and the main model in occlusogingival (y1) and buccolingual (z2) dimensions in both time periods, but Speedex failed to show a significant difference in the same dimensions and time periods. In the y2 dimension in contrast to Irasil, Speedex demonstrated a significant decrease of dimensional stability.
Conclusion
Timing did not affect the dimensions of the two impression materials. The mesiodistal dimensions (x) of both Speedex and Irasil increased on the casts. A significant difference was found in dimensional stability between Speedex and Irasil impression materials.

Abstract Original: Persian
The effect of mechanical surface conditioning methods on the shear bond strength of repaired composites

Parnian Alizadeh Oskuee *, Narmin Mohammadi, Siavash Savadi Oskuee, Ali Hoseini Page 31

Background And Aim
Considering the cost and quantity of tooth loss in the process of cavity preparation, repairing composite restorations instead of replacing them would be much more efficient. The aim of this study was to evaluate and compare the effectiveness of different mechanical surface treatment methods on the shear bond strength (SBS) between old and new composites.
Materials And Methods
In this experimental in vitro study, 80 cylindrical specimens were fabricated from Tetric Ceram Composite (A1, vivadent) and were preserved in 370c distilled water. They were divided into 4 groups according to the surface treatment
Method
control (no treatment), roughening by a diamond bur, polishing with Sof-Lex disks and air-abrasion. All specimens were thermocycled (0.5-550c, 500 cycles) prior to testing for SBS. An Instron Universal Testing Machine (5mm/min Cross head imm) was used to evaluate the SBS of the specimens. Data were analysed by one-way ANOVA and Duncan tests.
Results
The highest to lowest shear bond strengths were seen in the Sof-Lex disk, air abrasion, diamond bur and control groups, respectively. A significant difference was observed between all three experimental groups (air abrasion, diamond bur, Sof-Lex disk) and the control group. There were no significant differences between the air abrasion and diamond bur groups, but the other groups revealed a significant difference when compared as pairs. Adequate wetting and induction of a microretentive surface, may explain the high SBS observed in the Sof-Lex group.
Conclusion
The results of this study emphasize the importance of mechacinal surface conditioning prior to composite restoration repair.

Abstract View Paper Original: Persian
Adenoid ameloblastoma with dentinoid (Case Report)

Shila Gasemi Moridani Page 38

Background And Aim
Ameloblastoma is one of the most common odontogenic tumors, occasionally with unusual features. In this study an uncommon odontogenic tumor, histologically similar to ameloblastoma and adenomatoid odontogenic tumor with hard tissue formation is reported. Case Report: A 19-year old female presented with a unilocular lesion on the right side of the maxilla, extending from the canine to the first molar. The tumor tissue was unicystic overall and typical plexiform ameloblastoma was observed in some areas. Dentinoid formation and tubular dentin was observed in the tumor stroma, whereas enamel matrix was not seen.
Conclusion
Very few cases of this variant of ameloblastoma have been reported and the name “adenoid ameloblastoma with dentinoid” is suggested for these lesions.

Abstract View Paper Original: Persian
Comparison of the use of silk sutures and cyanoacrylate tissue glue after periodontal flaps in patients with moderate periodontitis

Ahmad Mogharehabed, S.Hesam Mirmohammadi Page 44

Background And Aim
The use of silk suturing materials and cyanoacrylate tissue glue are common in wound closure after periodontal surgeries, gingival grafts, tumor removal, etc. The aim of this study was to compare the use of silk sutures and cyanoacrylate tissue glue (EPIGLU) in wound closure after periodontal flaps in patients with moderate periodontitis.
Materials And Methods
This experimental study was conducted on fifteen patients (10 female, 5 male) aged 25-55 years with moderate periodontitis in need of flap surgery on both sides. After a Widman modified surgical flap, the incision lines were randomly closed with silk sutures on one side (control group) and EPIGLU on the other side (study group). The patients were followed for 2 weeks post surgery and the two groups were compared in terms of pain, bleeding, wound healing, sensitivity and tissue compatibility. Sign and Friedman tests were used to compare the results.
Results
The use of EPIGLU showed no significant differences with silk sutures in most cases but the differences became more prevalent with time.
Conclusion
Considering the favorable properties of EPIGLU such as improved wound healing, less bleeding, superior clinical performance, minimal chair time and patient acceptability, it is suggested as a replacement for silk sutures.

Abstract View Paper Original: Persian
An In - Vitro study on the effect of Iranian soft drinks on enamel microhardness of primary teeth

Behjatolmolok Ajami *, Masoomeh Ebrahimi, Sedigheh Karbasi Page 51

Background And Aim
Diet is the most important etiologic factor in dental erosion. Erosion of dietary origin in children is frequently related to carbonated drinks and acidic foods. The aim of this study was to evaluate the effects of some acidic soft drinks on enamel micro-hardness of primary teeth.
Materials And Methods
This interventional in vitro study was performed on 40 healthy deciduous teeth. Enamel blocks were prepared and were polished on their external surfaces using water and sand paper. The baseline hardness was measured using Vickers microhardness measuring apparatus. The enamel blocks were then immersed in 20cc Coca Cola, Zam Zam, Pepsi and Ab-Ali yoghurt-drink for 5 minutes and their microhardness was assessed. The data were analyzed using co-variance and paired sample t-tests.
Results
The baseline hardness in primary teeth, was 378.4 31.65 (kg/mm2) for Coca Cola, 373.57 30.31 (kg/mm2) for Zam Zam, 378.38 21.92 (kg/mm2) for Pepsi and 385.43 34.79(kg/mm2) for Ab-Ali yoghurt-drink, before being placed in the experimental soft drinks. After immersion (second hardness), these values decreased to 333.02 32.15 (kg/mm2), 339.65 20.91 (kg/mm2), 342.27 28.01 (kg/mm2) and 341.46 32.34 (kg/mm2) for Coca Cola, Zam Zam, Pepsi and Ab-Ali yoghurt soft drinks, respectively. The reduction in microhardness was statistically significant for each of the tested soft drinks but a statistically significant difference was not observed between the study groups.
Conclusion
The intake of soft drinks such as Coca Cola, Zam Zam, Pepsi and Ab-Ali yoghurt-drink can reduce enamel microhardness in primary teeth.

Abstract View Paper Original: Persian

علمی مصوب

Journal of Islamic Dental Association of IRAN

مجله دندانپزشکی جامعه اسلامی دندانپزشکان

دوفصلنامه پزشکی به زبان انگلیسی

آخرین شماره | آرشیو

ISSN: 1024-6428

از سال 2016 بصورت انگلیسی منتشر می شود.

صاحب امتیاز:

جامعه اسلامی دندانپزشکان

مدیر مسئول:

دکتر محمدصادق احمدآخوندی

سردبیر:

دکتر مسعود فلاحی نژاد قاجاری

تلفن نشریه: ۰۲۱-۸۸۸۹۲۳۷۷

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فهرست مطالب

Journal of Islamic Dental Association of IRAN Volume:18 Issue: 2, 2006

Journal of Islamic Dental Association of IRAN

مجله دندانپزشکی جامعه اسلامی دندانپزشکان

Journal of Islamic Dental Association of IRAN
Volume:18 Issue: 2, 2006