Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 1 2015 02 15 1 10 Hossein Aghili Associate Professor, Department of Orthodontics, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Abbas Ali Jafari Nadoushan Associate Professor, Department of Medical Parasitology and Mycology, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Vahid Herandi Dentistry Student, Dentistry School, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. 2015 10 16 Long-term use of orthodontic appliances and fixation ligatures creates a favorable environment for the accumulation of oral normal microflora and increases the risk of enamel demineralization and periodontal disease. The aim of this study was to compare the antimicrobial effects of Zataria Multiflora extract and 0.2% chlorhexidine (CHX) mouthwash on experimentally contaminated orthodontic elastomeric ligatures.In this lab trial study, Iranian and foreign-made elastomeric ligatures were experimentally contaminated in Streptococcus mutans, Enterococcus faecalis and Candida albicans suspensions. Ligatures were then decontaminated using 0.2% CHX as the control, 0.5 mg/ml Zataria multiflora extract mouthwashes as the test and phosphate buffered saline (PBS) as the negative control for one hour. Antimicrobial properties of both solutions were evaluated by comparing the mean viable bacterial cell count on both rings after decontamination, using SPSS version 15 software.The mean viable bacterial cell count on Iranian ligatures was greater than that on foreign-made ligatures before disinfection (P=0.001), however this difference for C. albicans was not statistically significant (P=0.061). Chlorhexidine mouthwash completely eliminated all tested microorganisms attached to both elastomeric rings, but Zataria extract was only capable of completely eliminating C. albicans from both ligatures. Statistically significant differences were found in viable bacterial counts on both ligatures before and after disinfection with Zataria extract (P=0.0001).Zataria multiflora extract has antimicrobial properties and can be used for disinfection of elastomeric ligatures. In vivo studies are required to evaluate the efficacy of the incorporation of this herbal extract in mouthwashes for orthodontic patients. https://fid.tums.ac.ir/index.php/fid/article/view/379 https://fid.tums.ac.ir/index.php/fid/article/download/379/355

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 1 2015 02 15 11 7 Beheshteh Malekafzali Associate Professor, Department of Pediatric, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Maliheh Ekrami Post Graduate Student, Department of Operative, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Armin Mirfasihi Dental Student, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Zahra Abdolazimi Post Graduate Student, Department of Pediatric, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 2015 10 16 Although fluoridated toothpastes are among the most accessible fluoride sources for caries prevention, their remineralization potential remains questionable. This study sought to compare the effects of 5 different child formula dentifrices on remineralization of artificial primary enamel caries using a pH cycling model.Twenty sound primary canine teeth were immersed in demineralizing solution for 96 hours to produce 100μm-deep artificial caries. The teeth were then longitudinally sectioned into 100-150 μm-thick slices and randomly divided into 5 groups and treated as follows: group A. Calcium phosphate toothpaste, group B. Pooneh children's toothpaste, group C. Biotin toothpaste, group D. Crest children's toothpaste and group E. Darougar children's toothpaste. The specimens underwent a pH cycling model for 10 days. The degree of demineralization before and after treatment and its changes were evaluated under a polarized light microscope and a stereomicroscope and data were statistically analyzed using repeated measures ANOVA and post-hoc test.Stereomicroscopic analysis showed that only group C had a significant difference with other groups (P0.05). Polarized light microscopic analysis revealed that in addition to group C, a significant difference was detected between groups A and B (P=0.02) and calcium phosphate toothpaste showed higher efficacy.All the understudy toothpastes had remineralizing effect but calcium phosphate children's toothpaste had the highest and biotin toothpaste had the lowest efficacy. https://fid.tums.ac.ir/index.php/fid/article/view/377 https://fid.tums.ac.ir/index.php/fid/article/download/377/353

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 1 2015 02 15 18 24 Nahid Ramazani Assistant Professor, Children and Adolescent Health Research Center, Department of Pediatric Dentistry, Faculty of Dentistry, Zahedan University of Medical Sciences, Zahedan, Iran. Mina Ranjbar Dentist, Zahedan University of Medical Sciences, Zahedan, Iran. 2015 10 16 Incomplete adaptation of stainless steel crown margins leads to microleakage. The aim of this study was to evaluate the effect of tooth preparation on microleakage of stainless steel crowns (SSCs) placed on mesiodistally reduced primary mandibular first molars.In this In vitro study, 60 primary mandibular first molars with reduced mesiodistal dimension were selected. Pulp cavities were filled with amalgam and occlusal surfaces were reduced. The samples were randomly divided into two groups (groups P and BLP). Standard preparation was done in group P with only proximal reduction. In group BLP, after reducing the proximal undercuts, buccal and lingual surfaces were slightly reduced. Occlusal one-third of the buccal surfaces was beveled in both groups. Then, the SSCs of the primary maxillary and mandibular first molars were fitted and cemented in P and BLP groups, respectively. After immersing the samples into deionized water, thermo-cycling, and immersion in 2% basic fuchsin, the samples were sectioned buccolingually. The mesial halves were evaluated microscopically for microleakage in both buccal and lingual margins. Data were analyzed using Mann-Whitney U test in SPSS 19 at the significant level of 0.05.There was a significant difference in microleakage of the buccal margin (P=0.003); whereas, the difference observed in the lingual margin was not significant (P=0.54).We suggest reduction of buccal and lingual surfaces of mesiodistally reduced primary mandibular first molars and placing lower (mandibular) crowns. https://fid.tums.ac.ir/index.php/fid/article/view/375 https://fid.tums.ac.ir/index.php/fid/article/download/375/351

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 1 2015 02 15 25 30 Sedigheh Khedmat Dental Research Center, Dentistry Research Institute, Department of Endodontics, School of Dentistry, Tehran University of Medical Sciences, and Iranian Center for Endodontic Research, Tehran, Iran. Alaleh Hashemi Undergraduate student, School of Dentistry, International Campus of Tehran University of Medical Sciences. Tehran, Iran. Fatemeh Dibaji Department of Endodontics, School of Dentistry, International Campus of Tehran University of Medical Sciences. Tehran, Iran. Mohammad Javad Kharrazifard Statistical Advisor, Dental Research center, Tehran University of Medical Sciences, Tehran, Iran. 2015 10 16 This study aimed to assess the effect of chloroform, eucalyptol and orange oil solvents on the microhardness of human root dentin.Sixty-eight single-rooted single-canal extracted human premolar teeth were used. Tooth crowns were separated from the roots at the cementoenamel junction (CEJ). Roots were buccolingually sectioned into mesial and distal halves. Specimens were randomly divided into 5 groups, with 20 teeth in each solvent group and 4 teeth in each control group. Primary microhardness of specimens was measured using Vickers microhardness tester. Specimens were exposed to solvents for 15 minutes and were subjected to microhardness testing again. Data were recorded and analyzed using repeated measure ANOVA.No significant difference was found in dentin microhardness before and after exposure to solvents in any of the orange oil, eucalyptol, chloroform or saline groups (P=0.727). None of the experimental groups showed any significant difference in terms of dentin microhardness reduction (P=0.99) and had no significant difference with the negative control group.This study showed that chloroform, eucalyptol and orange oil as gutta percha solvents did not decrease the microhardness of root dentin. Thus, none of the mentioned solvents has any superiority over the others in terms of affecting dentin properties. https://fid.tums.ac.ir/index.php/fid/article/view/373 https://fid.tums.ac.ir/index.php/fid/article/download/373/349

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 1 2015 02 15 31 8 Mojgan Paknejad Associtate Professor, Dental Research Center Dentistry Research Institute, Department of Periodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran ; Dental Implant Research Center, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. AmirReza Rokn Dental Implant Research Center, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran ; Professor, Department of Periodontoics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Nina Rouzmeh Assistant Professor, Department of Periodontics, School of Dentistry, Qom University of Medical Sciences, Qom, Iran. Mohadeseh Heidari Assistant Professor, Department of Periodontics, School of Dentistry, Mazandaran University of Medical Sciences, Mazandaran, Iran. Azadehzeinab Titidej Assistant Professor, Department of Oral and Maxillofacial Pathology, School of Dentistry, Qazvin University of Medical Sciences, Qazvin, Iran. Mohammad Javad Kharazifard Statistical Advisor, Dental Research center, Tehran University of Medical Sciences, Tehran, Iran. Ali Mehrfard Student, Islamic Azad University. 2015 10 16 Considering the importance of bone augmentation prior to implant placement in order to obtain adequate bone quality and quantity, many studies have been conducted to evaluate different techniques and materials regarding new bone formation. In this study, we investigated the bone healing capacity of two different materials deproteinized bovine bone mineral (DBBM with the trade name of Bio-Oss) and demineralized freeze-dried bone allograft (DFDBA with the trade name of DynaGraft).This randomized blinded prospective study was conducted on twelve New Zealand white rabbits. Three cranial defects with an equal diameter were created on their calvarium. Subsequently, they were distributed into three groups: 1. The control group without any treatment; 2. The Bio-Oss group; 3. The DynaGraft group. After 30 days, the animals were sacrificed for histologic and histomorphometric analysis.Substantial new bone formation was observed in both groups. DynaGraft: 56/1 % ± 15/1 and Bio-Oss: 53/55 % ± 13/5 compared to the control group: 28/6 % ± 11/2. All groups showed slight inflammation and a small amount of residual biomaterial was observed.Considerable new bone formation was demonstrated in both DynaGraft and Bio-Oss groups in comparison with the control group. Both materials are considered biocompatible regarding the negligible foreign body reaction. https://fid.tums.ac.ir/index.php/fid/article/view/371 https://fid.tums.ac.ir/index.php/fid/article/download/371/347

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 1 2015 02 15 39 48 Nasrin Farhadian Associate Professor, Department of Orthodontics, Faculty of dentistry, Hamadan University of Medical Sciences, Hamadan, Iran. Amirfarhang Miresmaeili Associate Professor, Department of Orthodontics, Faculty of dentistry, Hamadan University of Medical Sciences, Hamadan, Iran. Ramin Azar Assistant Professor, Department of Orthodontics, Faculty of dentistry, Hamadan University of Medical Sciences, Hamadan, Iran. Massoumeh Zargaran Assistant Professor, Dental Research Center, Department of Oral and Maxillofacial Pathology, Faculty of dentistry, Hamadan University of Medical Sciences, Hamadan, Iran. Abbas Moghimbeigi Associate Professor, Modeling of Noncommunicable Disease Research Center, Department of Biostatistics and Epidemiology, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran. Sanaz Soheilifar Assistant Professor, Department of Orthodontics, Faculty of dentistry, Hamadan University of Medical Sciences, Hamadan, Iran. 2015 10 16 After maxillary expansion, a long period of retention is necessary to prevent early relapse. Therefore, it is beneficial to accelerate bone formation in the expanding midpalatal suture to reduce relapse. This study was designed to evaluate the effect of dietary vitamin C on osteogenesis of rat midpalatal suture during expansion.Fifty-four male Wistar rats were randomly divided into three groups, each with a control and an experimental subgroup. An open-loop spring was bonded to maxillary incisors of each animal to expand the premaxillary suture. Experimental groups received dietary vitamin C in their water. The rats in the three groups were sacrificed at three, nine or 17-day intervals after bonding the spring. Then, the premaxilla was dissected and sections were made and stained with hematoxylin and eosin and osteopontin marker. Osteoblasts and osteoclasts were counted in the suture. Two-way ANOVA and the Mann-Whitney-U test were used for analyzing the data.After three days, the number of osteoblasts was significantly higher in the vitamin C group but after nine days it was significantly higher in the control group and after seventeen days there were no significant differences between the groups. Osteoclast counts were not significantly different between vitamin C and control groups.Vitamin C had a positive effect on osteogenesis at the beginning of bone formation in the expanding suture, but after nine days it had a negative effect on suture osteogenesis in rats. https://fid.tums.ac.ir/index.php/fid/article/view/369 https://fid.tums.ac.ir/index.php/fid/article/download/369/345

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 1 2015 02 15 49 59 Farzin Heravi Department of Orthodontics, School of Dentistry Mashad University of Medical Sciences, Mashhad, Iran. Mohamad Hadi Moayed Department of Materials and Metallurgical Engineering, Ferdowsy University, Mashhad, Iran. Nima Mokhber Department of Orthodontics, Academic Center of Education, Culture and Research (ACECR), Mashhad, Iran. 2015 10 16 The commonly used Nickel-Titanium (NiTi) archwires in orthodontic treatment are often exposed to fluoride-containing mouthwashes. The aim of this in-vitro study was to evaluate and comh> 16 Despite the current use of radiography for quantifying sagittal skeletal measurements, it is an unsuitable way for screening or epidemiologic purposes. Although not fully approved, anthropometric measurements have been suggested as a substitute, and considering displacement of soft tissues, could possibly lead to more consistent results. The purpose of this study was to evaluate the reliability of anthropometric anteroposterior facial measurements under soft tissue compression using a special ruler.Anthropometric measurements were done with a specifically designed sliding ruler twice on 36 adult patients with a 14 day lag between two measurements. The ruler measured the distance between the external acoustic meatus and the nasion (Na), subnasal (Sn) point and the soft tissue pogonion (Pog). The soft tissue was displaced during measurements only to the extent that the underlying hard tissue resistance was felt subjectively by each assessor. The intraclass correlation coefficient (ICC) was calculated for both inter- and intra- rater measurements using SPSS software.All measurements had inter- and intrarater agreements above 0.9, with only a few parameters having lower bound confidence intervals below 0.9, but more than 0.8.Sagittal facial anthropometric measurements under soft tissue displacement using the specific ruler are valid and reliable and could possibly aid orthodontists in chairside craniofacial assessments. https://fid.tums.ac.ir/index.php/fid/article/view/678 https://fid.tums.ac.ir/index.php/fid/article/download/678/653

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 2 2013 03 15 169 74 Beheshteh Malekafzali Associate professor, Department of Pedodontics, Shahid Beheshti University of Medical Science Dental School, Tehran, Iran. Amir Ghasemi Hassan Torabzadeh Reza Hamedani Nekoo Tadayon 2015 10 16 Multiple adhesive coating is a controversial topic, especially in primary dentition that should be clarified. We evaluated the effect of multiple consecutive adhesive resin coatings on the microshear bond strength (μSBS) of composite resin to primary tooth dentin utilizing a filled (Adper Single Bond Plus) and an unfilled (Adper Single Bond) adhesive resin.Thirty extracted primary canines were randomly allocated into two groups based on the adhesive used. Dentin occlusal surfaces were exposed and further polished on 400, 600 and 800-grit silicon-carbide paper. The surfaces were divided into two halves in the labial-lingual orientation. After etching, the adhesives were used either in double coats, or four coats on the halves of the same tooth followed by air evaporation for each layer and finally light curing. Cylinders of composite were bonded to the dentin surfaces. After 24 h shear bond testing was evaluated by Bisco tensile tester. ANOVA, Student t test and paired t test were used for statistical analysis.The mean (standard deviation) for double coats or four coats in single bond were 31.99 (2.94) and 30.25 (2.69), while they were 29.18 (3.35) and 31.26 (2.07) in single bond plus, respectively. No significant differences were found between the double coated specimens and those receiving four coatings with both adhesives (p>0.05). Micro SBS values of Single Bond double coated specimens were significantly higher than Single Bond Plus (p=0.02). In four-coated specimens, there were no significant differences between Single Bond and Single Bond Plus (p=0.26).Applying four coats of adhesive did not improve the μSBS to primary tooth dentin. https://fid.tums.ac.ir/index.php/fid/article/view/676 https://fid.tums.ac.ir/index.php/fid/article/download/676/651

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 2 2013 03 15 175 85 Abdollah Ghorbanzadeh Assistant Professor, Department of Endodontic Dentistry, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Soran Aminifar Leila Shadan Hamed Ghanati 2015 10 16 To compare three various methods in the diagnosis of dentinal cracks formed in the apical third after root resection.One hundred extracted human maxillary central incisors were selected. The root canals were prepared with step-back technique. Then 3mm from the apical end of all roots was cut perpendicular to the long axis of the tooth. The apical end of each root was evaluated to make sure there were no cracks. Fifty specimens were randomly chosen and connected to an apparatus especially designed for application of force (50-60N) by a universal testing machine for crack formation. The cracked (no=50) and non-cracked (no=50) specimens were examined by three methods of fiber optic transillumination, methylene blue staining and combination of the two. Sensitivity and specificity of the methods were evaluated. The most suitable method for detecting cracks was determined using Youden index. To compare agreement between studied methods with the gold standard, kappa statistics and odds ratio of McNemar were utilized.The sensitivity of transillumination, staining and the combination method were 82.0, 50.0 and 90.0%, respectively. The staining technique had the lowest sensitivity and the highest specificity. Both transillumination and the combination method had Youden index of 0.56, but the combination method diagnosed truly cracked samples more than the other techniques.The efficacy of transillumination in identification of apical root-end cracks undetectable by unaided vision was similar to the combination method. However, the efficacy of 2% methylene blue without transillumination was significantly lower than the other two methodologies. https://fid.tums.ac.ir/index.php/fid/article/view/674 https://fid.tums.ac.ir/index.php/fid/article/download/674/649

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 2 2013 03 15 186 96 Mandana Naseri Assistant Professor, Department of Endodontics,Dental School of Shahid Beheshti University of Medical Sciences, Tehran, Iran. Ali Kangarlou Haghighi Mohammad Javad Kharazifard Atefeh Khavid 2015 10 16 Because of the great challenges in the diagnosis and treatment of "C" configuration and lack of any systematic information about its occurrence, the purpose of the present study is to determine the prevalence of C shaped root canals in Iranian population.An exhaustive search was undertaken to identify published and unpublished researches related to the C-shaped canals by using key words. The search of the MEDLINE database included all publications from 1966 to May 2012.Then selected articles were obtained and reviewed. Data evaluated and summarized in the data sheet included methodology, population, number of teeth per study (power), number of root canals, type of root canal configuration, and c-shaped canals.Six studies were included with total of 1062 teeth, all in mandibular second molars. The total incidence of C-shaped canals in Iranian population was obtained 6.96%.The incidence of