ORIGINAL_ARTICLE
Microleakage of Posterior Composite Restorations with Fiber Inserts Using two Adhesives after Aging
Statement of Problem: Microleakage is one of the most frequent problems associated with resin composites, especially at the gingival margin of posterior restorations. Insertion of fibers in composite restorations can reduce the total amount of composite and help to decrease the shrinkage.Purpose: The aim of this study was to evaluate the effect of polyethylene fiber inserts on gingival microleakage of class II composite restorations using two different adhesive systems.Materials and Method: In this experimental study, class II cavities were prepared on 60 premolars. The gingival floor was located 1.0 mm below the CEJ. Dimension of each cavity were 3 mm buccolingually and 1.5 mm in axial depth. The specimens were divided into 4 groups according to the adhesive type and fiber insert (n=4). Single bond and Clearfill SE bond and Filtek p60 were used to restore the cavities. In groups without fiber inserts composite was adapted onto cavities using layering technique. For cavities with fiber inserts, 3 mm piece of fiber insert was placed onto the composite increment and cured. The specimens were stored in distilled water at 37oC for 6 months. All specimens were subjected to 3000 thermo-cycling. The tooth surfaces except for 1 mm around the restoration margins covered with two layers of nail varnish .The teeth were immersed in 2% Basic Fuchsin for 24 hours, then rinsed and sectioned mesiodistally. The microleakage was determined under a stereomicroscope (40X). Data were statistically analyzed by Kruskal-wallis and Mann-Whitney U tests (p< 0.05).Results: The Kruskal-Wallis test revealed no significant differences in mean microleakage scores among all groups (p= 0.281).Conclusion: Use of polyethylene fiber inserts and etch-and-rinse and self-etch adhesives had no effect on microleakage in class II resin composite restorations with gingival margins below the CEJ after 6- month water storage.
https://dentjods.sums.ac.ir/article_41145_e795a0dd1cb3c7cea2d407eb093582a2.pdf
2013-09-01
90
95
F.
Sharafeddin
sharafeddinf@sums.ac.ir
1
Dept. of Operative Dentistry, Biomaterial Research Center, School of Dentistry, Shiraz University of Medical Science, Shiraz, Iran.
AUTHOR
H.
Yousefi
shiva.modiri@gmail.com
2
Dentist
AUTHOR
Sh.
Modiri
3
Post Graduate Student in Operative Dentistry, School of Dentistry, Shiraz University of Medical Science, Shiraz, Iran.
LEAD_AUTHOR
A.
Tondari
4
Post Graduate Student in Operative Dentistry, School of Dentistry, Shiraz University of Medical Science, Shiraz, Iran.
AUTHOR
SR.
Safaee Jahromi
5
Dept. of Operative Dentistry, School of Dentistry, Shiraz University of Medical Science, Shiraz, Iran.
AUTHOR
ORIGINAL_ARTICLE
Comparison of Dimensional Accuracy between Open-Tray and Closed-Tray Implant Impression Technique in 15° Angled Implants
Statement of Problem: Various impression techniques have different effects on the accuracy of final cast dimensions. Meanwhile; there are some controversies about the best technique.Purpose: This study was performed to compare two kinds of implant impression methods (open tray and closed tray) on 15 degree angled implants.Materials and Method: In this experimental study, a steel model with 8 cm in diameter and 3 cm in height were produced with 3 holes devised inside to stabilize 3 implants. The central implant was straight and the other two implants were 15° angled. The two angled implants had 5 cm distance from each other and 3.5 cm from the central implant. Dental stone, high strength (type IV) was used for the main casts. Impression trays were filled with poly ether, and then the two impression techniques (open tray and closed tray) were compared. To evaluate positions of the implants, each cast was analyzed by CMM device in 3 dimensions (x,y,z). Differences in the measurements obtained from final casts and laboratory model were analyzed using t-Test.Results: The obtained results indicated that closed tray impression technique was significantly different in dimensional accuracy when compared with open tray method. Dimensional changes were 129 ± 37μ and 143.5 ± 43.67μ in closed tray and open tray, while coefficient of variation in closed- tray and open tray were reported to be 27.2% and 30.4%, respectively.Conclusion: Closed impression technique had less dimensional changes in comparison with open tray method, so this study suggests that closed tray impression technique is more accurate.
https://dentjods.sums.ac.ir/article_41150_68af42cee43fe2466ca48e283517d25b.pdf
2013-09-01
96
102
F.
Balouch
dr.e.jalalian@yahoo.com
1
Dept. of Prosthodontics, Dental Branch, Islamic Azad University, Tehran, Iran.
AUTHOR
E.
Jalalian
2
Dept. of Prosthodontics, Dental Branch, Islamic Azad University, Tehran, Iran.
LEAD_AUTHOR
M.
Nikkheslat
3
DDS
AUTHOR
R.
Ghavamian
4
DDS
AUTHOR
Sh.
Toopchi
5
Dental Student, Dental Branch, Islamic Azad University. Tehran, Iran.
AUTHOR
F.
Jalalian
6
Post Graduate Student, Dept. of Radiology, Dental Faculty, Isfahan University of Medical Sciences, Isfahan, Iran.
AUTHOR
S.
Jalalian
7
Post Graduate Student, Dept. of Prosthodontics, Dental Branch, Islamic Azad University, Tehran, Iran.
AUTHOR
ORIGINAL_ARTICLE
A Comparison of Apical Root Resorption in Incisors after Fixed Orthodontic Treatment with Standard Edgewise and Straight Wire (MBT) Method
Statement of Problem: One of the major outcomes of orthodontic treatment is the apical root resorption of teeth moved during the treatment. Identifying the possible risk factors, are necessary for every orthodontist.Purpose: The aim of this study was to compare the rate of apical root resorption after fixed orthodontic treatment with standard edgewise and straight wire (MBT) method, and also to evaluate other factors effecting the rate of root resorption in orthodontic treatments.Materials and Method: In this study, parallel periapical radiographs of 127 patients imaging a total of 737 individual teeth, were collected. A total of 76 patients were treated by standard edgewise and 51 patients by straight wire method. The periapical radiographs were scanned and then the percentage of root resorption was calculated by Photoshop software. The data were analyzed by Paired-Samples t-test and the Generalized Linear Model adopting the SPSS 15.0.Results: In patients treated with straight wire method (MBT), mean root resorption was 18.26% compared to 14.82% in patients treated with standard edgewise technique (p< .05). Male patients had higher rate of root resorption,statistically significant (p< .05). Age at onset of treatment, duration of treatment, type of dental occlusion, premolar extractions and the use of intermaxillary elastics had no significant effect on the root resorption in this study.Conclusion: Having more root resorption in the straight wire method and less in the standard edgewise technique can be attributed to more root movement in pre-adjusted MBT technique due to the brackets employed in this method.
https://dentjods.sums.ac.ir/article_41151_2907aaa2bbaa284d63c6dc5105540171.pdf
2013-09-01
103
110
SM.
Zahed Zahedani
1
Postgraduate Student of Oral & Maxillofacial Medicine, Dept. Oral & Maxillofacial Medicine, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
LEAD_AUTHOR
M.
Oshagh
2
Orthodontics Research Center, Dept. of Orthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
AUTHOR
Sh.
Momeni Danaei
arman.khozaei@yahoo.com
3
Orthodontics Research Center, Dept. of Orthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
AUTHOR
SMM.
Roeinpeikar
4
Orthodontics Research Center, Dept. of Orthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
AUTHOR
ORIGINAL_ARTICLE
Effect of a Combined Bleaching Regimen on the Microhardness of a Sealed Methacrylate-based and a Silorane-based Composite
Statement of Problem: The use of tooth bleaching agents has been very popular treatment in dentistry. The bleaching agents have an inherent potential to impair surface properties of existing composite resin restorations.Purpose: This study evaluated the effect of a combined bleaching regimen on the surface microhardness of a Silorane-based and a sealed methacrylate-based composite.Materials and Method: Forty-five specimens of methacrylate-based composite (Ice) and 18 specimens of Silorane composite (Filtek Silorane, 3M ESPE; USA) were prepared and randomly divided into 5 (1-5) and 2 (6-7) groups (n=9), respectively. After 8-week aging, groups 1 and 6 were remained with no treatment. In groups 2, 4 and 5, the specimens were covered by a surface sealant and light cured. In groups 3, 4, 5 and 7, the specimens were bleached with hydrogen peroxide 40% and then carbamide peroxide 20% for seven days. In group 5, after bleaching, the sealant was removed by polishing. Surface microhardness was measured and the data were analyzed using one-way ANOVA and Tukey tests (α=0.05). Results: The microhardness values of groups 2 to 4 were significantly lower than that of group1 (p <0.05). There was no significant difference among groups 1, 5, 6 and 7 (p> 0.05).Conclusion: The combined bleaching regimen used in this study had a substantial negative effect on methacrylate and sealed methacrylate composites but not on Silorane composite. Polishing following the bleaching on the sealed composite yielded a hardness value similar to that of unsealed methacrylate composite (control).
https://dentjods.sums.ac.ir/article_41152_398d42b8ecfe5166d6a8feb89402d180.pdf
2013-09-01
111
117
F.
Shafiei
sam_dft@yahoo.com
1
Dept. of Operative Dentistry, Biomaterial Research Center, School of Dentistry, Shiraz Uni
AUTHOR
S.
Doustfatemeh
2
Undergraduate Student, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
LEAD_AUTHOR
ORIGINAL_ARTICLE
Comparison the Marginal and Internal Fit of Metal Copings Cast from Wax Patterns Fabricated by CAD/CAM and Conventional Wax up Techniques
Statement of Problem: Metal-ceramic crowns are most commonly used as the complete coverage restorations in clinical daily use. Disadvantages of conventional hand-made wax-patterns introduce some alternative ways by means of CAD/CAM technologies.Purpose: This study compares the marginal and internal fit of copings cast from CAD/CAM and conventional fabricated wax-patterns.Materials and Method: Twenty-four standardized brass dies were prepared and randomly divided into 2 groups according to the wax-patterns fabrication method (CAD/CAM technique and conventional method) (n=12). All the wax-patterns were fabricated in a standard fashion by means of contour, thickness and internal relief (M1-M12: representative of CAD/CAM group, C1-C12: representative of conventional group). CAD/CAM milling machine (Cori TEC 340i; imes-icore GmbH, Eiterfeld, Germany) was used to fabricate the CAD/CAM group wax-patterns. The copings cast from 24 wax-patterns were cemented to the corresponding dies. For all the coping-die assemblies cross-sectional technique was used to evaluate the marginal and internal fit at 15 points. The Student’s t- test was used for statistical analysis (α=0.05).Results: The overall mean (SD) for absolute marginal discrepancy (AMD) was 254.46 (25.10) um for CAD/CAM group and 88.08(10.67) um for conventional group (control). The overall mean of internal gap total (IGT) was 110.77(5.92) um for CAD/CAM group and 76.90 (10.17) um for conventional group. The Student’s t-test revealed significant differences between 2 groups. Marginal and internal gaps were found to be significantly higher at all measured areas in CAD/CAM group than conventional group (p< 0.001). Conclusion: Within limitations of this study, conventional method of wax-pattern fabrication produced copings with significantly better marginal and internal fit than CAD/CAM (machine-milled) technique. All the factors for 2 groups were standardized except wax pattern fabrication technique, therefore, only the conventional group results in copings with clinically acceptable margins of less than 120um.
https://dentjods.sums.ac.ir/article_41153_22d7cdf824f6ac59f45d24ca5ac57dea.pdf
2013-09-01
118
129
M.
Vojdani
1
Dept. of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
AUTHOR
K.
Torabi
salehipegah84@gmail.com
2
Dept. of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
LEAD_AUTHOR
E.
Farjood
3
Postgraduate Student, Dept. of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
AUTHOR
AAR.
Khaledi
4
Dept. of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
AUTHOR
ORIGINAL_ARTICLE
Comparison of the Effect of two Denture Cleansers on Tensile bond Strength of a Denture Liner
Statement of Problem: One of the most clinical challenging issues in prosthodontics is debonding of soft liners from the denture base.Purpose: The aim of this study was to evaluate and compare tensile bond strength between soft liner and heat-cured acrylic resin when immersed in two different types of denture cleanser and distilled water, at different period of times. Materials and Method: In this experimental in vivo study, 238 heat-cured acrylic blocks were made. A soft liner was embedded between the acrylic blocks. Samples were divided into four groups: 17 samples were in the control group and were not soaked in any solution .The remaining samples were divided into 3 groups (Distilled water, Calgon and Fittydent). Each group was then subdivided into two subcategories, regarding the immersion time variable; 15 and 45 minutes. All samples were placed in tension force and tensile bond strength was recorded with the testing machine. One- way ANOVA and Tucky HSD post-hoc test were adopted to analyze the yielded data (α> 0.05).Results: Specimens which were immersed in two denture cleansers (Fittydent and Calgon) and in distilled water showed significant difference (p= 0.001) in bonding strength when compared to the control group. The subjects immersed in denture cleanser solutions and distilled water did not reveal any significant difference (p= 0.90). For all groups; most of the bonding failures (72%) were cohesive type. Conclusion: The effect of the denture cleansers and distilled water on the bond strength was not statistically different; however, the difference was significant between the immersed groups with the non-immersed group. Moreover, type of the denture cleanser did not show any effect on the tensile strength. The tensile strength increases with time of immersion.
https://dentjods.sums.ac.ir/article_41154_778393bcf6d1669f5e2bcc6bd8b94f1d.pdf
2013-09-01
130
135
M.
Farzin
fbahrani@sums.ac.ir
1
Dept. of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
AUTHOR
F.
Bahrani
derafshi@sums.ac.ir
2
Dept. of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
LEAD_AUTHOR
E.
Adelpour
3
Dentist
AUTHOR
ORIGINAL_ARTICLE
Dentin Hypersensitivity: Etiology, Diagnosis and Treatment; A Literature Re-view
The objective of this review is to inform practitioners about dentin hypersensitivity (DH); to provide a brief overview of the diagnosis, etiology and clinical management of dentin hypersensitivity and to discuss technical approaches to relieve sensitivity. This clinical information is described in the context of the underlying biology.The author used PUBMED to find relevant English-language literature published in the period 1999 to 2010. The author used combinations of the search terms “dentin*”, “tooth”, “teeth”, “hypersensit*”, “desensitiz*”. Abstracts and also full text articles to identify studies describing etiology, prevalence, clinical features, controlled clinical trials of treatments and relevant laboratory research on mechanisms of action were used.
https://dentjods.sums.ac.ir/article_41148_223585e93300e55a49af15dc3de58e72.pdf
2013-09-01
136
145
AR.
Davari
ataei@dnt.mui.ac.ir
1
Dept. of Operative Dentistry, School of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
AUTHOR
E.
Ataei
2
Dept. of Operative Dentistry, School of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
AUTHOR
H.
Assarzadeh
3
Postgraduate Student of Operative Dentistry, Dept. of Operative Dentistry, School of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
LEAD_AUTHOR
ORIGINAL_ARTICLE
Delay in the Diagnosis and Treatment of Oral Cancer
Statement of Problem: Oral and pharyngeal cancer is one of the most mortal cancers; however, its quick diagnosis and referral is a crucial factor in enhancing the survival rate of the patients.Purpose: The aim of this study was to inspect the referral conditions and the reasons for the delay in curing the patients referred to the educational hospitals in Tehran.Materials and Method: In this retrospective -descriptive study, two hundred and fifty six files related to the oral and pharyngeal cancer were inspected. The documents were obtained from 5 educational hospitals specialized in the field of cancers. Eventually data related to the time difference between the first time of attending to lesion and diagnosing the cancer as patient’s delay and until the curing as professional’s delay were recorded.Results: The majority of cancers were squamous cell carcinoma (SCC). The patient’s delay was recorded in 110 files among the whole files. The mean of the time between the patients’ first notice of the problem and the time visiting a primary care clinician was 270 days (range, 0-2520 days). The mean of the time from when the patient visited a primary- care clinician to the starting time of definitive treatment was 90 days (range, 0-270 days).Conclusion: In this study, like other studies, SCC was the most common occurring cancer. Delays related to the patients were more than those related to the professionals. And at last, accuracy in recording the files and training the patients were recognized to be the most imperative factors to continue the treatment successfully.
https://dentjods.sums.ac.ir/article_41147_c232fea9ae4db9910f9d054ff4d9630e.pdf
2013-09-01
146
150
A.
Jafari
najafi_sh@tums.ac.ir
1
Dept. of Dental Research Center and Community Oral Health, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
AUTHOR
Sh.
Najafi
2
Dept. of Oral Medicine, International Campus, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
Dept. of Dental Research Center and Oral Medicine, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
LEAD_AUTHOR
F.
Moradi
3
Postgraduate Student, School of Dentistry, Yazd University of Medical Sciences, Yazd, Iran.
AUTHOR
MJ.
Kharazifard
4
Statistical Consultant, School of Dentistry, Tehran University of Medical Sciences. Tehran, Iran.
AUTHOR
MR.
Khami
5
Dept. of Dental Research Center and Community Oral Health, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
AUTHOR
ORIGINAL_ARTICLE
Non-Syndromic Multiple Odontogenic Keratocyst: A Case Report
Odontogenic keratocyst (OKC) is a common developmental odontogenic cyst affecting the maxillofacial region. Multiple OKCs are usually seen in association with nevoid basal cell carcinoma syndrome (NBCCS) but approximately 5% of patients with OKC have multiple cysts without concomitant syndromic presentation. This report represents a case of multiple OKCs in a non-syndromic patient.
https://dentjods.sums.ac.ir/article_41146_a9ad918995894ce8b898ea1840849653.pdf
2013-09-01
151
154
N.
Kargahi
1
Dept. of Oral and Maxillofacial Pathology and Torabinejad Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran.
AUTHOR
M.
Kalantari
2
Post Graduate, Dept. of Oral and Maxillofacial Pathology and Torabinejad Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran.
LEAD_AUTHOR
ORIGINAL_ARTICLE
Letter to Editor
Dear Sir Recently, all aspects of life have been changed & impressed by revolution of computer science. Education, as one of the most important part of life, is also affected by improvements such as Internet and E-books. Traditional books at least to some extent are slowly replaced by electronic and digital publications. These, could be produced massively in less time and lower price which means simple accessibility all around the word.Today, instead of participating in boring classes, students can play the digital manuscripts of lectures as many times as they want at any time of the day, without getting out of the home. This eliminates the time needed for transport and its fees and risks.In addition to potentials of multimedia used in these techniques which simplifies the process of learning, questions and tests may be applied in these digital lectures which give the user the choice to evaluate the learning process, so the student will play a more active role in process of education. Many advantages of electronic education make it desirable for most of titles. So, today, it is becoming a scale of evaluation of education institutes, i.e., the more the titles instructed by means of digital education, the higher the rank of the institute.Digital education, in our country, although not really new, comprises a very minor part of education. Tradition classes are still the most popular method for teaching, which imparts its fees.We have many things to do to benefit fully from potential advantage of digital education. Obviously preparing the needed hardware background is of utmost importance. Beside, lessons should be prepared in digital form and some percent of education assigned to E-learning.Regarding the need, software, for introducing the basics of radiology, is prepared in radiology department in Shiraz dental school as a student thesis. The composition of X-ray tube, the mechanism of X-ray production, the composition of radiographic film, latent image formation and film processing are described in this software, by means of video films, animations and photographs. This software can be used by dental students before entering radiology department, to simplify the understanding of basic principles of dental radiology. The software is presented in the website: http://hsoft.ir80.com as Review of Dental Radiology Basics Software and can be downloaded freely. Future revised forms also will be available.We hope that this software can help dental students to become familiar with some Far-fetched principles of radiology and acts as a starting point for developing E-learning in radiology department and other parts of our dental schools.
https://dentjods.sums.ac.ir/article_41149_9899ba7f0d72867847397287634b20d0.pdf
2013-09-01
AA.
Haghnegahdar
1
Dept. of Oral Radiology, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
AUTHOR
P.
Bronoosh
2
Dept. of Oral Radiology, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
AUTHOR
H.
Jami
3
Student Research Center, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
LEAD_AUTHOR