@article{ author = {Shamaei, Mahmood and Taleghany, Feryal and Kiany, Azadeh and Kharazifard, Mohammad jav}, title = {Clinical evaluation of Bio-Oss alone and in combination with PRP in the treatment of grade II mandibular molar furcation defects}, abstract ={Clinical evaluation of Bio-Oss alone and in combination with PRP in the treatment of grade II mandibular molar furcation defects Dr. M. Shamaei* - Dr. F. Taleghany* - Dr. A. Kiany** - Dr. MDJ. Kharazifard*** *Assistant Professor of Periodontics Dept., Faculty of Dentistry, Shahed University. **Dentist. ***Statistical editor of Research & statistic Center, Faculty of Dentistry, Tehran University of Medical Sciences. Background and Aim: Furcation involvement is a condition in which the destruction of interradicular periodontium occurs in the branching area of multirooted teeth, for which different treatment modalities have been suggested. The aim of this study was to compare the response of grade II mandibular molar furcation defects to Bio-oss versus Platelet Rich Plasma (PRP) and Bio-oss treatment. Materials and Methods: In this randomized clinical trial, five patients with bilateral grade II furcation involvement of mandibular molars were selected from those referred to the School of Dentistry, Shahed University of Medical Sciences. The molars were treated with Bio-oss and PRP on one side and Bio-oss on the other side. Measurements of the probing pocket depth (PPD), and clinical attachment level (CAL) were recorded at baseline, 1.5 and 3 months after surgery. Wilcoxon signed-rank test was used for statistical analysis.Results: At 1.5 and 3 months after surgery, the mean PPD reduction in the middle area of the furcation, was 2.4±1.67 mm and 3±2.0 mm in the test and 1±1.22 mm and 1.1±0.89 mm in the control groups, respectively. The mean attachment gain at the same place was 1.6±0.54 mm at 1.5 months and 1.8±0.44 mm at 3 months in the test group, and 1.5±1.0mm at 1.5 months and 1.4±1.34 mm at 3 months in the control group. Conclusion: The results of this study showed no significant difference between treatment with Bio-Oss with and without PRP in regeneration of grade II furcation involvement. Key words: Furcal involvement - Bio-Oss - Platet rich plasma}, Keywords = {Furcal involvement , Bio-Oss , Platet rich plasma}, volume = {19}, Number = {1}, pages = {7-12}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-216-en.html}, eprint = {http://jida.ir/article-1-216-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Ghoddusi, Jamileh and Ghaziani, Pari and Nazari, Shahrz}, title = {Comparison of remaining obturating material on canal walls using rotary and hand instrumentation techniques for endodontic re-treatment}, abstract ={Comparison of remaining obturating material on canal walls using rotary and hand instrumentation techniques for endodontic re-treatment Dr. J. Ghoddusi*- Dr. P. Ghaziani*- Dr. Sh. Nazari** *Associate Professor of Endodontics Dept., Faculty of Dentistry, Mashhad University of Medical Sciences. **Assistant Professor of Endodontics Dept., Faculty of Dentistry, Hamedan University of Medical Sciences. Background and Aim: Inadequate removal of the original obturating material during non-surgical endodontic retreatment may lead to failure of root-canal therapy. The purpose of this in vitro study was to quantify and compare the percentage of root canal area occupied by remaining gutta-percha, employing rotary and hand instrumentation techniques with and without use of chloroform. Materials and Methods: Ninety extracted single-rooted human teeth were prepared by a passive step-back technique in three different working lengths: optimum increased (over-instrumented) and reduced (under-instrumented). Obturation was performed by a combination of cold lateral and warm vertical compaction methods. The teeth were divided into 3 groups according to the methods used for gutta-percha removal: Group A, stainless steel K-type hand files plus chloroform Group B, rotary Ni-Ti files plus chloroform and Group C, rotary Ni-Ti files without chloroform. The roots were sectioned longitudinally and the percentage of root canal area occupied by root-filling material was calculated by a digital stereomicroscope in three levels: coronal, middle and apical. Data were analyzed by ANOVA. Results: The coronal two-thirds contained larger amounts of filling material in all 3 groups, but the difference was not significant. A significantly smaller amount of gutta-percha/sealer was found in the middle and apical thirds in group C (P<0.05). The relative percentage of canal area occupied by obturating material was not significantly different among the 3 working-lengths.Conclusion: The use of rotary files without solvent resulted in cleaner canals. However, completely clean root canal walls were not achieved with any of the studied instruments. Key words: Rotary instrumentation technique - Re-treatment - Obturating material - Chloroform}, Keywords = {Rotary instrumentation technique , Re-treatment , Obturating material , Chloroform}, volume = {19}, Number = {1}, pages = {13-20}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-217-en.html}, eprint = {http://jida.ir/article-1-217-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Darabi, Faride and Mirfazaelian, Ali and Naseri, Haleh}, title = {The survival rate of fiber-reinforced composite inlay bridges after two million load cycles: An in vitro study}, abstract ={The survival rate of fiber-reinforced composite inlay bridges after two million load cycles: An in vitro study Dr. F. Darabi* - Dr. A. Mirfazaelian** - Dr. H. Naseri*** *Assistant Professor of Operative Dentistry Dept. - Faculty of Dentistry – Guilan University of Medical Sciences. **Assistant Professor of Removable Prosthodontics Dept. Faculty of Dentistry – Tehran University of Medical Sciences. ***Dentist. Background and Aim: Fiber reinforced composite (FRC) inlay bridges have become popular for being conservative, simple and relatively inexpensive. The aim of this in vitro study was to determine the survival rate of FRC inlay bridges replacing missing maxillary lateral incisors, after being subjected to a cyclic mechanical load of 2 million cycles with a force of 30 N at a frequency of 2 Hz. Materials and Methods: In this experimental study, 30 anterior bovine teeth were used as abutments to make 15 anterior FRC inlay bridges. Fifteen acrylic resin blocks were fabricated utilizing a dentoform. The teeth were mounted in the resin blocks while trying to simulate normal tooth angulations, PDL and biologic width. Pontics were made indirectly and bridges were directly fabricated in 222 mm prepared cavities using Nulite F fiber- reinforced composite resin and polyethylene fiber based braids (NSI, Australia). The specimens were thermocycled for 2000 cycles between 5°C and 55°C and were then exposed to two million load cycles (30 N, 2 Hz) at 130°C to the long axis of the pontics (3mm under the incisal edge) in a cyclic loading machine. Results: Three specimens were excluded due to experimental mishandling. All 12 remaining bridges (%100) survived the applied loads. Conclusion: Based on the results of this study, it may be concluded that FRC bridges can tolerate more than 2 million normal masticatory forces which is equivalent to 7-9 years of clinical service. Key words: Survival Rate - Inlay bridges - Composite}, Keywords = {Survival Rate , Inlay bridges , Composite}, volume = {19}, Number = {1}, pages = {21-27}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-218-en.html}, eprint = {http://jida.ir/article-1-218-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Vatanpour, Mehdi and Javidi, Maryam}, title = {Evaluation of different clearing techniques: An auxiliary method for studying root canal anatomy}, abstract ={Evaluation of different clearing techniques: An auxiliary method for studying root canal anatomy Dr. M. Vatanpour* - Dr. M. Javidi** * Resident of Endodontics Dept., Faculty of Dentistry, Mashhad University of Medical Sciences. ** Assistant Professor of Endodontics Dept., Faculty of Dentistry, Mashhad University of Medical Sciences.Background and Aim: Various techniques for clearing the root canal system have been used in different aspects of dentistry. Poor quality of the final cleared tooth may affect accurate evaluation of the anatomy or other characteristics of the canals. The purpose of this study was to compare a number of currently used clearing methods in order to identify the most effective procedure. Materials and Methods: Fifty human extracted premolars were included in this experimental study. A routine clearing protocol was employed for all teeth. The specimens were divided into 5 groups of 10, applying different combinations of decalcifying (HCL, HNO3) and clearing agents (eugenol, methyl salicylate). The samples were examined by two endodontists. Data were subjected to statistical analysis using Chi-square and Kruskal Wallis tests. Results: A significant difference was observed between the study groups. The most effective decalcifying material and clearing agent was %10 HCl and methyl salicylate, respectively. Conclusion: According to the results of the present investigation, application of %10 HCl along with methyl salicylate is suggested for the evaluation of the root canal system. Key words: Clearing technique - Root canal anatomy - Transparent tooth}, Keywords = {Clearing technique , Root canal anatomy , Transparent tooth}, volume = {19}, Number = {1}, pages = {28-33}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-219-en.html}, eprint = {http://jida.ir/article-1-219-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Sazgara, Hasan and Seyyedan, Kaveh and Majidi, Amir hossei}, title = {Effect of smear layer on the retention of custom made posts luted with two different cements}, abstract ={Effect of smear layer on the retention of custom made posts luted with two different cements Dr. H. Sazgara*- Dr. K. Seyyedan ** - Dr. A.H. Majidi*** *Associate Professor of Fixed Prosthodontics Dept., Faculty of Dentistry, Shaheed Beheshti University of Medical Sciences.**Assistant Professor of Fixed Prosthodontics Dept., Faculty of Dentistry, Shaheed Beheshti University of Medical Sciences. ***Assistant Professor of Fixed Prosthodontics Dept., Faculty of Dentistry, Qazvin University of Medical Sciences. Background and Aim: Post retention has a considerable effect on restorative treatments and is influenced by various factors. The purpose of this study was to evaluate the effect of dentinal smear layer on the retention of custom-made posts luted with composite resin and zinc phosphate cements. Materials and Methods: Forty single-rooted lower premolars were decoronated, filed and filled with gutta-percha and divided into 4 equal groups. Post spaces were prepared to a length of 8 mm. Direct post patterns were made with acrylic resin and castings were fabricated using Ni-cr alloy. In Groups A and C, the post spaces were rinsed with 2 ml of 0.9% normal saline. The specimens in Groups B and D were rinsed with 1 ml of 17% EDTA followed by 1 ml of 5.25% Naocl and 10 ml distilled water. After drying, ZPC (Dentsply) was used for cementation in groups A and B. The samples in Groups C and D were luted with Panavia F2.0. Retention was measured on a Universal Testing Machine at 0.5 m/min. Data were subjected to statistical analysis using ANOVA. Results: The mean amount of retention was 19.66±1.98 kg, 19.72±2.08 kg, 20.99±2.08 kg and 22.17±3.66 kg in groups A, B, C and D, respectively. There was no significant difference between the groups, but the mean value was highest in group D. Conclusion: The use of resin cement provided greater retention for custom-made posts compared to ZPC. Removing dentinal smear layer did not significantly affect the retention of custom-made posts cemented with ZPC or Panavia F2.0. Key words: Smear layer - Custom-made post - Resin cement - Zinc phosphate cement - Retention}, Keywords = {Smear layer , Custom-made post , Resin cement , Zinc phosphate cement , Retention}, volume = {19}, Number = {1}, pages = {34-42}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-220-en.html}, eprint = {http://jida.ir/article-1-220-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Bidar, Maryam and Zarei, Mina and Madani, Azamosadat and Kharazifard, Mohammad jav}, title = {Comparison of the remaining smear layer following use of manual and rotary instruments with various speeds}, abstract ={Comparison of the remaining smear layer following use of manual and rotary instruments with various speeds Dr. M. Bidar* - Dr. M. Zarei** - Dr. A.A Madani***, Dr. MDJ. Kharazifard**** * Associate Professor of Endodontics Dept., Faculty of Dentistry, Mashhad University of Medical Sciences. ** Assistant Professor of Endodontics Dept., Faculty of Dentistry, Mashhad University of Medical Sciences. *** Assistant Professor of Prosthodontics Dept., Faculty of Dentistry, Mashhad University of Medical Sciences.**** Statistical editor of research & statistic center, Faculty of Dentistry, Tehran University of Medical Sciences Background and Aim: Endodontic smear layer (SL) can reduce the apical seal and adaptation of gutta-percha to root canals (RCs). Instruments with adequate flexibility and proper speed create less smear during RC preparation. The purpose of this in vitro study was to compare the amount of SL following canal preparation by hand and rotary instrumentation. Materials and Methods: Sixty freshly extracted single-rooted teeth with minimum curvatures were divided into two groups. All canals in group 1 were instrumented with SS-type K-files using a step-back technique. The remaining teeth constituting group 2 were divided into 3 subgroups and prepared by employing the GT profile system at rotational speeds of 1000, 8000, and 24000 rpm. In both groups, 2 teeth were selected as controls, which were placed in 17% EDTA for 15 minutes and then washed with 5.25% Naocl. All specimens were cut bucco-lingually, and evaluated under an electron microscope. Kruskal-Wallis and Man-Whitney U tests were used to compare the groups. Results: A significant difference in the amount of SL was not observed between the three rotational speeds at the coronal portions of the RCs. These sections were cleaner in the 1000 and 24000 rpm groups. No significant difference was found between the two instrumentation techniques in the apical portions. The mean size of the smear plug was larger and showed a greater amount of attachment in group 1 as compared to group 2. Conclusion: Ni-Ti rotary instruments produced a thinner SL with less attachment to the root canal walls making it easy to remove with sufficient irrigation. Key words: Electron microscope – Smear layer - Rotary instruments}, Keywords = {Electron microscope , Smear layer , Rotary instruments}, volume = {19}, Number = {1}, pages = {43-49}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-221-en.html}, eprint = {http://jida.ir/article-1-221-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {MogharehAbed, Ahmad and E'tesampoor, Mohamm}, title = {Comparison of silk sutures and 2–ethyl–cyanoacrylate on wound closure following surgical crown lengthening using apically positioned flap surgery}, abstract ={Comparison of silk sutures and 2–ethyl–cyanoacrylate on wound closure following surgical crown lengthening using apically positioned flap surgery Dr. A. Moghareh Abed* - Dr. M. E'tesampoor*** Assistant Professor of Periodontics Dept., Faculty of Dentistry, Isfahan University of Medical Sciences. ** Dentist. Background and Aim: The use of cyanoacrylate tissue glue as an alternative to silk sutures has increased due to its various advantages. The purpose of this experimental study was to compare the clinical outcome of surgical crown lengthening using silk sutures and 2–ethyl–cyanoacrylate. Materials and Methods: Thirty-two individuals with no history of systemic diseases and good oral hygiene were selected from patients referred to the Department of Periodontics, School of Dentistry, Isfahan University of Medical Sciences. Following apically positioned flap surgery, the wounds were closed by silk sutures and 2–ethyl–cyanoacrylate in the control and experimental groups, respectively. Bleeding, pain and healing-time were evaluated 1, 2, 3, and 10 days postoperatively. Sign and Friedman tests were used for statistical analysis. Results: A significant difference was observed in bleeding between the two groups at days 1 and 2 (P<0.01) but not days 3 and 10. In both groups, the bleeding index decreased significantly with time. Pain indices were significantly different between the two groups on the first and second days (P<0.01, P<0.05), but not the third and tenth days. Wound healing significantly improved in the test - as compared to the control group at day 10 (P<0.05). The two groups showed no significant difference in terms of infection at day 10. Conclusion: The use of cyanoacrylate in crown lengthening surgery can improve wound healing and reduce bleeding and pain, especially compared to suturing techniques. However, the differences between these two methods decrease with time. Key words: Suture - Tissue glue - Crown lengthening - Appically positioned flap}, Keywords = {Suture , Tissue glue , Crown lengthening , Appically positioned flap}, volume = {19}, Number = {1}, pages = {50-55}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-222-en.html}, eprint = {http://jida.ir/article-1-222-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Seyyedan, Kaveh and Kalalipoor, Maryam and Javan, Mehdi}, title = {Silane and bonding of Resins to Ceramic}, abstract ={Silane and bonding of Resins to Ceramic Dr. K. Seyyedan* - Dr. M. Kalalipoor** - Dr. M. Javan***Assistant Professor of Fixed Prosthodontics Dept., Faculty of Dentistry, Shaheed Beheshti University of Medical Sciences. **Resident of Fixed Prosthodontics Dept., Faculty of Dentistry, Shaheed Beheshti University of Medical Sciences. Background and Aim: When bonding between two different dental materials is impossible due to structural dissimilarity, a third material can be used at the interface to achieve the desired bond. Silanes have been developed for this purpose and can improve bonding strength in dental restorations by preventing debonding at the interface region. The present study reviewed the relevant publications in order to determine the effect of silane on the bond strength of ceramic to resin restorations. Materials and Methods: Multiple internet search engines including Google, AltaVista, and the archives of related Journals were used in order to access information on the properties of silane. Conclusion: Application of silane increases the bonding strength between composite and resin by approximately 25%, regardless of different fabrication and testing methods. Etching with phosphoric acid and treatment with silane emerged as the two most significant factors in the improvement of the bonding strength of cements. However, using an appropriate coupling agent even without etching has also been shown to produce an acceptable bonding strength. Hydrolyzed silanes do not produce methanol and therefore cannot completely vaporize the water generated during chemical reactions. On the other hand, non-hydrolyzed silanes vaporize surface water by producing 3 methanol molecules and thus do not interfere with bonding of adhesive systems. Therefore the bonding strength of non-hydrolized silanes is greater than hydrolyzed silanes. In conclusion, the type of silane (hydrolyzed, non-hydrolyzed), the adhesive used and the technique of its application are considered to be three of the most important factors affecting bond strength. Key words: Silane bonding agents - Bond strength - Resin-Ceramic bond}, Keywords = {Silane bonding agents ,Bond strength ,Resin, Ceramic bond}, volume = {19}, Number = {1}, pages = {56-64}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-223-en.html}, eprint = {http://jida.ir/article-1-223-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Sabooni, Mohammad reza and Ghanbarzadeh, Jalil and Ebrahimzadeh, Saeed and MoadyRodsari, Ali}, title = {Comparison of flexure resistance between two rod and paste solders in base metal alloy}, abstract ={Comparison of flexure resistance between two rod and paste solders in base metal alloy Dr. MR. Sabooni* - Dr. J. Ghanbarzadeh*- S. Ebrahimzadeh** - Dr. A. Moady Rodsari *** * Assistant Professor of Dental Prostheses Dept., Faculty of Dentistry, Mashhad University of Medical Sciences. ** Member of Faculty of Nursing, Mashhad University of Medical Sciences. *** Member of Communicative Medicine and Biostatistics Dept., Mashhad University of Medical Sciences. Background and Aim: Soldering is used in fixed prosthodontics, for different purposes such as connecting separate parts of the bridge, recontouring proximal and occlusal contacts and repairing casting voids. The aim of this study was to compare the flexural resistance of two rod and paste solders used in base metal alloys. Materials and Methods: Thirty rectangular specimens (1×4×30 mm) were made using super cast base alloy. The samples were sectioned into two equal parts and were placed in a soldering investment as pairs with 0.3 mm gaps between them. They were divided into 2 groups and soldered with rod solder in one group and paste solder in the other. The samples were subjected to a flexure test on a Universal Testing Machine. Statistically analysis was performed using F- and t-tests. Results: The minimum and maximum flexural resistance was 107.2N and 301.2N for the rod- and 62.8N and 109.3N for the paste solders, respectively. The mean flexural resistance was 196.5N in the rod solder group and 89.8N in the paste solder group. A significant difference in flexural resistance was observed between the two study groups (P=0.001). Conclusion: The results of this study indicated that flexural resistance of the rod solders was significantly higher than the paste solders. Key words: Soldering - Base alloy - Flexure resistance}, Keywords = {Soldering , Base alloy , Flexure resistance}, volume = {19}, Number = {1}, pages = {65-70}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-224-en.html}, eprint = {http://jida.ir/article-1-224-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Hagimiragha, Habib and Fallahzadeh, Farnoosh and Tayebi, Ali}, title = {Anterior tooth display in patients referred to the Faculty of Dentistry,Tehran University of Medical Sciences}, abstract ={Anterior tooth display in patients referred to the Faculty of Dentistry,Tehran University of Medical Sciences Dr. H. Hagimiragha* - Dr. F. Fallahzadeh** - Dr. A. Tayebi*** * Assistant Professor of Fixed Prosthodontics Dept., Faculty of Dentistry, Tehran University of Medical Sciences. ** Assistant Professor of Operative Dentistry Dept., Faculty of Dentistry, Qazvin University of Medical Sciences. *** Orthodontist. Background and Aim: Central incisors are important in achieving facial aesthetics and correct phonetics. This study evaluated the amount of incisal edge exposure (IEE) of upper and lower central incisors (UCIs, LCIs) with the lips in resting position, and its correlation with patients’ age and sex. The present investigation was also designed to assess practical methods for clinical evaluation of patients. Materials and Methods: One-hundred twenty patients between 20-49 years were included in this study. None of the participants had gingival recession, periodontal/gingival diseases, traumatized lips, tooth mobility/extrusion or prostheses replacing anterior teeth. Age, sex and occlusal and molar relationships (Angle’s classification) were recorded. IEE, Incisogingival length (IgL) of the UCIs and LCIs and lip length (LL) in resting position were measured for each patient using a metal ruler. IEE, IgL and LL were analyzed according to sex and age by t-test. Fischer’s exact test was used to verify the relation between IEE and Ig with LL. Results: The mean averages of IEE and IgL of the UCIs and LCIs were larger in men than women however the difference was not significant in LCIs. The mean average of LL was 24.07mm and 21.2mm in males and females, respectively. IEE decreased in the UCIs and increased in the LCIs with advancing age, but this difference was not significant in the LCIs. The following formula was calculated according to the obtained data: IEE-Right-Upper = 5.29 – 0.16 LL IEE-Left-Upper = 5.18 - 0.159 LL Conclusion: These findings can be used as a diagnostic aid for selecting appropriate IEEs allowing maximum dentofacial aesthetics. Key words: Incisal Edge Exposure - Incisogingival length - Lip length}, Keywords = {Incisal Edge Exposure , Incisogingival length , Lip length}, volume = {19}, Number = {1}, pages = {71-77}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-225-en.html}, eprint = {http://jida.ir/article-1-225-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Abdolsamadi, Hamid reza and Kasraie, Shahi}, title = {Comparison of serum interleukin-8 levels in patients with recurrent aphthous stomatitis and healthy individuals}, abstract ={Comparison of serum interleukin-8 levels in patients with recurrent aphthous stomatitis and healthy individuals Dr. HR. Abdolsamadi* - Dr. Sh. Kasraie** * Assistant Professor of Oral Medicine Dept., Faculty of Dentistry, Hamadan University of Medical Sciences. ** Assistant Professor of Operative Dentistry Dept., Faculty of Dentistry, Hamadan University of Medical Sciences. Background and Aim: Recurrent aphthous stomatitis (RAS) is one of the most common inflammatory diseases affecting the oral mucosa therefore an increase in pro-inflammatory cytokines like IL-8 may be expected. The aim of this study was to compare serum IL-8 levels in patients with RAS and healthy individuals. Materials and Methods: Eighty patients without a history of systemic disease were selected from those referred to the Department of Oral Medicine, School of Dentistry, Hamadan University of Medical Sciences, during May 2005 to Feb 2006. The study and control groups consisted of 40 patients (19 males and 21 females mean age, 25.08 years) with RAS and 40 healthy cases (23 males and 17 females mean age, 25.5 years), respectively. Whole blood (10/ml) was obtained from all participants and the serum was separated and stored at -70ºC, until used. Serum IL-8 levels were measured by ELISA. Statistical analysis was performed using t-test (p<0.01). Results: The mean serum IL-8 level was 52.24 pg/ml in the RAS group and 5.01 pg/ml in the control group which showed a 10-fold increase in RAS patients (P<0.01). These levels were greater than the upper limit of normal serum concentration in 35 (87.5%) of the RAS subjects (16 males, 19 females) and was within normal range in 5 (12.5%) cases (3 males, 2 females). Thirty-seven (92.5%) of the healthy individuals demonstrated normal levels while 3 (7.5%) showed increased amounts. Conclusion: In this study, a significant increase in the mean serum IL-8 level was observed in the RAS group. Key words: Cytokines - Interleukin-8 - Recurrent aphthous ulcers}, Keywords = {Cytokines , Interleukin-8 , Recurrent aphthous ulcers}, volume = {19}, Number = {1}, pages = {78-82}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-226-en.html}, eprint = {http://jida.ir/article-1-226-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Ghanbarzadeh, Jalil and Sabooni, Mohammad reza and Keshavarz, Masou}, title = {Effect of pontic width on stress distribution in abutment teeth and their supporting structures by finite element analysis}, abstract ={Effect of pontic width on stress distribution in abutment teeth and their supporting structures by finite element analysis Dr. J. Ghanbarzadeh* - Dr. MR. Sabooni* - Dr. M. Keshavarz** * Assistant Professor of Dental Prostheses Dept., Faculty of Dentistry, Mashhad University of Medical Sciences. ** Assistant Professor of Dental Prostheses Dept., Faculty of Dentistry, Kerman University of Medical Sciences. Background and Aim: Fixed partial dentures and single restorations reveal differences in the pattern and quantity of stress. The most important factors affecting stress distribution in abutments are occluso-gingival height and bucco-lingual width. In this in vitro study a finite element analysis was performed to evaluate changes in the pattern and quantity of stress in pontics with different widths. Materials and Methods: Three PFM models were created, one with a conventional width and the other two demonstrating 20% and 40% width-reduction. The models were fabricated to replace a mandibular first molar. A load of 700 N was applied vertically to the center of the pontic and the stress patterns were examined by finite element analysis. Results: Maximum stress concentration was observed in the supporting bone of the abutment teeth mesial to the premolars, distal to the molars and in the apical portions of the premolars. The 20% and 40% width-reduction of the pontics caused a similar amount of stress reduction in the supporting tissues of the abutment teeth. Stress concentration sites were also observed at the furcation area and the cervical regions of the distal aspect of the premolars and mesial aspect of the molars. The reduction in stress values within tooth structure was proportional but less than the 20% and 40% width-reduction of the pontics. Conclusion: Reduction of pontic width caused a considerable amount of stress reduction in the supporting bone and a smaller amount in tooth structure. Key words: Stress – Bridge - Finite element analysis - Pontic}, Keywords = {Stress , Bridge , Finite element analysis , Pontic}, volume = {19}, Number = {1}, pages = {83-89}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-227-en.html}, eprint = {http://jida.ir/article-1-227-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Vojdani, Mahro and Dehbozorgi, Gholamreza and Mohammadzadeh, Sasan and AkbariJahromi, Alirez}, title = {Comparison of anxiety and depression in patients with temporomandibular disorders and healthy individuals}, abstract ={Comparison of anxiety and depression in patients with temporomandibular disorders and healthy individuals Dr. M. Vojdani* - Dr. Gh.R. Dehbozorgi** - Dr. S. Mohammadzadeh*** - Dr. A. Akbari Jahromi*** * Assistant Professor of Dental Prostheses Dept., Faculty of Dentistry, Shiraz University of Medical Sciences. ** Assistant Professor of Psychiatry Dept., Faculty of Medicine, Shiraz University of Medical Sciences. *** Dentist. Background and Aim: Psychological factors have been suggested to play a role in the maintenance and etiology of temporomandibular disorders (TMDs), but its exact cause is complicated and multifactorial. This study aimed to compare anxiety and depression between patients with TMD and matched healthy individuals. Materials and Methods: A total of 150 individuals including 75 TMD patients and 75 healthy volunteers were included in this case-control investigation. The participants were matched according to age, sex, occupation and socio-economic status. In order to collect demographic and general health information, all subjects were asked to fill-out questionnaires. Symptoms of anxiety were measured with the Spielberger State-Trait Anxiety Inventory (STAI) scale and symptoms of depression with the Beck Depression Inventory (BDI) scale. Data were analyzed using Chi-square, independent sample T-test and two-way ANOVA with SPSS software. Results: The mean score for BDI was 15.2 in the case and 8.36 in the control groups, which showed a significant difference. BDI was not significantly different between males and females. State and Trait scores were significantly higher in the TMD patients as compared to the controls. A significant difference was not observed in Trait anxiety between the two sexes but men revealed significantly higher State anxiety scores than women. Conclusion: These findings indicate that depression and anxiety were more prevalent among TMD patients in comparison to the normal population. Therefore psychological consultation for both men and women with TMD should be considered in the treatment plan. Key words: Temporomandibular disorder – Depression - Anxiety.}, Keywords = {Temporomandibular disorder , Depression , Anxiety}, volume = {19}, Number = {1}, pages = {90-96}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-228-en.html}, eprint = {http://jida.ir/article-1-228-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {EsmailiSari, Abbas and Zolfaghari, Ghasem and Ghasempouri, S.Mahmood and Shayegh, S,Shojaeddin and HasaniTabatabei, Masoomeh}, title = {Effect of Age, Gender, Years of Practice, Specialty and Number of Amalgam restorations on Mercury Concentration in Nails of dentists practicing in Tehran}, abstract ={Effect of Age, Gender, Years of Practice, Specialty and Number of Amalgam restorations on Mercury Concentration in Nails of dentists practicing in Tehran Dr. A. Esmaili Sari* - Gh. Zolfaghari** - S.M. Ghasempouri***- Dr. S.Sh. Shayegh****, Dr. M. Hasani Tabatabei***** * Associate Professor of Environment Dept., Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University ** M.Sc of Environment Dept., Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University *** Member of Environment Dept., Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University **** Assistant Professor of Prosthodontics Dept., Faculty of Dentistry, Shahed University. *****Assistant Professor of Operative Dentistry Dept., Faculty of Dentistry, Tehran University of Medical Sciences. Background and Aim: Dental professionals are at risk of being exposed to inorganic mercury, through handling amalgam. The purpose of the present investigation was to evaluate the effect of age, sex, years of practice, specialty and number of amalgam fillings on the concentration of mercury in nails of dentists practicing in Tehran. Materials and Methods: This analytic-descriptive study, conducted between May 2005 and May 2006, involved a randomly selected sample of 100 dentists and 35 controls in Tehran. All participants were asked to provide a nail sample and complete a questionnaire. Mercury was measured by the LECO AMA 254 Advanced Mercury Analyzer (USA) according to ASTM, standard No. D-6722. The LECO AMA254 is a unique Atomic Absorption Spectrometer (AAS) that is specifically designed to determine total mercury contents in various solids and certain liquids without sample pre-treatment or sample pre-concentration. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U-tests. Results: Mercury content in nails differed significantly among operative dentists: 0.14-27.27 mg/kg orthodontists: 0.15-14.53 mg/kg and controls: 0-1.7 mg/kg (p=0.000). Age had a significant effect on mercury concentrations (p=0.01). However, gender (p=0.93), years of practice (p=0.49), number of amalgam fillings (p=0.58) and the studied specialties (p=0.07) did not significantly affect mercury levels. Conclusion: Mercury levels were significantly higher in dentists and correlated with age. High mercury concentrations in some dentists appeared to be related to background exposure from the preparation of amalgam, amalgam residues and spillage of mercury. Key words: Mercury – Amalgam – Nail - Dentist}, Keywords = {Mercury , Amalgam , Nail , Dentist}, volume = {19}, Number = {1}, pages = {97-104}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-229-en.html}, eprint = {http://jida.ir/article-1-229-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} } @article{ author = {Moosavi, Horiyeh and Maleknejad, Fatemeh and Nasiraee, Eim}, title = {In-Vitro evaluation of fracture resistance of weakened roots restored with fiber posts and tooth-colored materials}, abstract ={In-Vitro evaluation of fracture resistance of weakened roots restored with fiber posts and tooth-colored materials Dr. H. Moosavi* - Dr. F. Maleknejad**- Dr. I. Nasiraee*** * Assistant Professor of Operative Dentistry Dept., Faculty of Dentistry, Mashhad University of Medical Sciences. ** Associate Professor of Operative Dentistry Dept., Faculty of Dentistry, Mashhad University of Medical Sciences. *** Dentist. Background and Aim: Restoration of endodontically-treated anterior teeth with weakened roots requires special attention. The purpose of this investigation was to compare the fracture resistance of experimentally weakened anterior roots reinforced with three different methods using tooth-colored materials. Materials and Methods: Forty human sound maxillary central incisors were used in this in vitro study. The crowns of 30 teeth were removed 2mm above the CEJ. After root-canal therapy, flared canals were simulated. The teeth were filled with D.T. light-post plus resin composite (Clearfil DC Core Automix) in group 1, D.T. light-post plus two accessory posts (Reforpin+Panavia F 2.0) in group 2 and D.T. light-post plus Panavia F 2.0 in group 3. Access cavities in the fourth (control) group were restored after ideal root-canal therapy. Following cementation of the posts and restoration of the crowns with Clearfil Photo-Core composite, the roots were embedded in acrylic resin blocks, 1 mm below the CEJ. After 24h storage, the samples were loaded in an Instron testing machine with a crosshead speed of 0.5 mm/min at a 45° angle to the long axis of the tooth on the palatal surfaces until failure. The data were analyzed using ANOVA and Tukey test (P=0.05). Results: The lowest (300.17 N) and highest (585.11 N) mean fracture resistance values were observed in the third and fourth groups, respectively (P<0.05). These values were not significantly different between the first, second and third groups. Conclusion: The results showed that Reforpin could be used as an alternative to resin composite for internal reinforcement of weakened roots. Key words: Weakened root - Fracture resistance - Resin composite.}, Keywords = {Weakened root , Fracture resistance , Resin composite}, volume = {19}, Number = {1}, pages = {105-111}, publisher = {Journal of Iranian Dental Association}, url = {http://jida.ir/article-1-230-en.html}, eprint = {http://jida.ir/article-1-230-en.pdf}, journal = {Journal of Iranian Dental Association}, issn = {2383-3041}, eissn = {}, year = {2007} }