Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 1 2013 01 30 1 9 Siamak Yaghobee Assistant Professor, Department of Periodontics & Dental Implant Research Center of Tehran University of Medical Sciences, Tehran, Iran. Afshin Khorsand Mojgan Paknejad 2015 10 16 Interleukin-1β (IL-1β) is one of the most important cytokines which seems to have an important role in the inflammatory process in gingival and peri-implant tissues. The aim of this split-mouth study was to investigate the relationship between the concentration of IL-1β in gingival crevicular fluid (GCF) and peri-implant crevicular fluid (PICF) and clinical parameters such as plaque index (PI), gingival index (GI), pocket depth (PD) and bone loss (BL).In 32 patients, PICF and GCF samples of 41 implants and 41 contralateral teeth were collected and IL-1β was determined by enzyme-linked immunosorbent assay (ELISA). PI,GI,PD and BL were recorded for each of the samples.The positive correlation between the level of IL-1β and PI, GI, PD and BL in both groups was observed (P https://fid.tums.ac.ir/index.php/fid/article/view/716 https://fid.tums.ac.ir/index.php/fid/article/download/716/692

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 1 2013 01 30 10 5 Fatemeh Ahmadi-Motamayel Associate Professor, Dental Research Center, Department of Oral Medicine, Dental school, Hamadan University of Medical Sciences, Hamadan, Iran. Seyedeh Sare Hendi Mohammad Yusof Alikhani Zahra Khamverdi 2015 10 16 Honey has antibacterial activity. The aim of this study was to evaluate the antibacterial activity of honey on Streptococcus mutans and Lactobacillus.In this in vitro study, solutions containing 0%, 5%, 10%, 20%, 50% and 100%(w/v) of natural Hamadan honey were prepared. Each blood (nutrient) agar plate was then filled with dilutions of the honey. The strains of bacteria were inoculated in blood agar for 24 hours at 37°C and were adjusted according to the McFarland scale (10×10 cfumcl(-1)). All assays were repeated 10 times for each of the honey concentrations. Data were analyzed by non parametric Chi-Square test. Statistical significance was set at α=0.05.Significant antibacterial activity was detected for honey on Streptococcus mutans in concentrations more than 20% and on Lactobacillus in 100% concentration (P https://fid.tums.ac.ir/index.php/fid/article/view/715 https://fid.tums.ac.ir/index.php/fid/article/download/715/690

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 1 2013 01 30 16 22 Amin Salem-Milani Assistant Professor, Department of Endodontics, Dental and Periodontal Disease Research Center, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran. Esrafil Balaei-Gajan Saeed Rahimi Zohreh Moosavi Ardalan Abdollahi Parvin Zakeri-Milani Mehrdad Bolourian 2015 10 16 Non-steroidal anti-inflammatory drugs (NSAIDs) have shown antibacterial activity in some recent studies. The aim of this study was to evaluate the antibacterial effect of diclofenac against Enterococcus faecalis (E. faecalis) as a resistant endodontic bacterium in comparison with ibuprofen, calcium hydroxide and amoxicillin.The antibacterial activity of materials was evaluated using agar diffusion test and tube dilution method. Mixtures of 400 mg/ml of materials were prepared. The bacteria were seeded on 10 Muller-Hinton agar culture plates. Thirty microliter of each test material was placed in each well punched in agar plates. After incubation, the zone of bacterial inhibition was measured. Minimum inhibitory concentration (MIC) of the test materials was determined by agar dilution method. One-way Analysis of Variance (ANOVA) followed by Sidak post hoc test was used to compare the mean zone of microbial growth in the groups.There were significant differences between the two groups (p< 0.05). Results of the agar diffusion test showed that antibiotics (amoxicillin, gentamycin) had the greatest antibacterial activity followed by NSAIDs (ibuprofen, diclofenac). Ca(OH)2 failed to show antibacterial activity. Diclofenac and ibuprofen showed distinct antibacterial activity against E. faecalis in 50 μg/ml and above concentrations.Within the limitations of this in vitro study, it is concluded that diclofenac and ibuprofen have significantly more pronounced antibacterial activity against E. faecalis in comparison with Ca(OH)2. https://fid.tums.ac.ir/index.php/fid/article/view/713 https://fid.tums.ac.ir/index.php/fid/article/download/713/688

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 1 2013 01 30 23 31 Parichehr Behfarnia Assistant Professor, Periodontics Department, Dental School, Isfahan University of Medical Sciences, Isfahan, Iran. Reza Birang Seyed Sajad Pishva Mazdak Ghanjalikhani Hakemi Mitra Mohammadi Khorasani 2015 10 16 The T helper 17 (Th17) cells have been suggested to have osteoclast activating effects while T helper 2 (Th2) cells are considered to have an osteoprotective role in periodontitis. This study was to compare the markers of Th17 cells (RORC2 and IL-17 genes) with that of Th2 cells (IL-4 and GATA-3 genes) between healthy and periodontitis tissues.The samples were obtained from patients with periodontitis and healthy tissues. The mRNA expression levels of IL-17, RORC2, IL-4 and GATA-3 were measured in both groups using quantitative RT-PCR. The results were compared using SPSS 11.0. Correlation coefficient was analyzed by Spearman's rho test. Mann-Whitney was used to measure the difference between IL-17 and IL-4 as well as RORC2 and GATA-3.In periodontal lesions, the expression levels of all markers were significantly higher than the healthy tissue (p≤ 0.001). The results showed a significant increase in the number of markers of Th17 (RORC2 and IL-17 genes) compared to markers of Th2 (GATA-3, IL-4) in patients with periodontitis compared to controls (p≤0.002). A positive correlation between IL-17 and RORC2 (p≤0.05) and between IL-4 and GATA-3 (p≤0.001) was found.The results show that expression levels of IL-4, GATA-3, IL-17 and RORC2 increase significantly in periodontal lesions compared with the controls. In periodontal lesions, IL-17 levels are significantly greater than IL-4, which plays a protective role against alveolar bone loss. https://fid.tums.ac.ir/index.php/fid/article/view/711 https://fid.tums.ac.ir/index.php/fid/article/download/711/686

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 1 2013 01 30 32 40 Maryam Khoroushi Associate Professor, Dental Materials Research Center and Department of Operative Dentistry, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran. Farinaz Shirban Mohammadreza Shirban 2015 10 16 In recent years, newly developed solvent-free dental adhesives have been introduced. The aim of this study was to evaluate the marginal integrity of a new one-step solvent-free self-etch adhesive and to compare it with a commonly used two-step self-etch adhesive as the gold standard.Class V cavities (2×4×1.5 mm) were prepared on the buccal aspects of 28 human premolars. The cervical margins of the cavity preparations were placed 1 mm apical to the CEJ. Clearfil SE Bond (CSEB) (two-step self-etch adhesive) and Bond 1SF (B1SF) (one-step self-etch adhesive) were applied to the cavities in groups 1 and 2 (n=14), respectively. Then, the specimens were restored with A2 shade of APX composite resin. Each group was evaluated for dye penetration under a stereomicroscope at ×32 after 24 hours and 500 rounds of thermocycling. Statistical analyses were carried out using Mann Whitney test (α=0.05). In addition, in each experimental group, two specimens were prepared for analysis under SEM.There were no significant differences in enamel margin microleakage between the two adhesives used (P=0.24(; whereas, there were significant differences in dentin margin microleakage between CSEB and B1SF (P=0.004). Dentin microleakage of B1SF was higher than that of CSEB.Results showed that the enamel marginal integrity of B1SF as a newly developed one-step solvent-free self-etch adhesive was similar to that of CSEB as a commonly used two-step self-etch; however, dentinal sealing of CSEB was better than that of B1SF. https://fid.tums.ac.ir/index.php/fid/article/view/709 https://fid.tums.ac.ir/index.php/fid/article/download/709/684

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 1 2013 01 30 41 50 Aboulfazl Saboury Dental Research Center, Research Institute of Dental Sciences of Shahid Beheshti University of Medical Sciences, Tehran, Iran ; Associate Professor, Department of Prosthodontics, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Seyed Jalil Sadr Ali Fayaz Minoo Mahshid 2015 10 16 High variability in delivering the target torque is reported for friction-style mechanical torque limiting devices (F-S MTLDs). The effect of aging (number of use) on the accuracy of these devices is not clear. The purpose of this study was to assess the effect of aging on the accuracy (±10% of the target torque) of F-S MTLDs.Fifteen new F-S MTLDs and their appropriate drivers from three different implant manufacturers (Astra Tech, Biohorizon and Dr Idhe), five for each type, were selected. The procedure of peak torque measurement was performed in ten sequences before and after aging. In each sequence, ten repetitions of peak torque values were registered for the aging procedure. To measure the output of each device, a Tohnichi torque gauge was used.Before aging, peak torque measurements of all the devices tested in this study falled within 10% of their preset target values. After aging, a significant difference was seen between raw error values of three groups of MTLDs (P https://fid.tums.ac.ir/index.php/fid/article/view/707 https://fid.tums.ac.ir/index.php/fid/article/download/707/682

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 1 2013 01 30 51 63 Sara Koosha Assisstant Professor, Department of Prosthodontics, Islamic Azad University of Medical Science, Branch of Dentistry, Tehran, Iran. Fatemeh Sadat Mirhashemi 2015 10 16 Tooth/implant supported fixed prostheses may present biomechanical design problems, as the implant is rigidly anchored within the alveolus, whereas the tooth is attached by the periodontal ligament to the bone allowing movement. Many clinicians prefer tooth/implant supported fixed prosthesis designs with rigid connectors. However, there are some doubts about the effect of attachment placement in different prosthesis designs. The purpose of this study was to examine the stresses accumulated around the implant and natural teeth under occlusal forces using three dimensional finite element analysis (3D FEA).In this study, different connection designs of tooth/implant fixed prosthesis in distal extension situations were investigated by 3D FEA. Three models with various connection designs were studied; in the first model an implant rigidly connected to an abutment, in the second and third models an implant connected to abutment tooth with nonrigid connector in the distal part of the tooth and mesial part of the implant. In each model, a screw type implant (5×11mm) and a mandibular second premolar were used. The stress values of these models loaded with vertical forces (250N) were analyzed.There was no difference in stress distribution around the bone support of the implant. Maximum stress values were observed at the crestal bone of the implant. In all models, tooth movement was higher than implant movement.There is no difference in using a rigid connector, non rigid connector in the distal surface of the tooth or in the mesial surface of an implant. https://fid.tums.ac.ir/index.php/fid/article/view/705 https://fid.tums.ac.ir/index.php/fid/article/download/705/680

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 10 1 2013 01 30 64 73 Javad Chalipa Assistant Professor, Orthodontic Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Mohammad Sadegh Ahmad Akhoundi Elinaz Shoshtarimoghaddam Tahereh Hosseinzadeh Nik Mosle Imani 2015 10 16 Cephalometry and its related analyses have an important role in the evaluation of orthodontic patients. Access to an analysis that gives maximum information in the least possible time is an effective way to indicate craniofacial disharmony; therefore, craniofacial templates are very useful tools. The purpose of the present study was to provide orthodontic craniofacial templates for 8-14-year-old Iranian girls.One thousand two-hundred and nine girls (age range, 8-14 years) were examined. Eighty of these cases were finally chosen for the study and their lateral cephalograms were traced. Both Basion-Nasion (Ba-N) and Sella-Nasion (S-N) lines were selected for superimposition in this study. Based on these two mentioned lines, a template for each age was designed. Simple linear regression and multivariant regression analysis were used to evaluate the angles and to landmark the vectors, respectively.Findings show that most points change significantly at different ages in the S-N method. In the Ba-N method, all points except for S and Ba have significant changes at different ages.Templates that resulted from both methods were the same and alteration in the reference line and points does not change the total form of the average tracings of each age. https://fid.tums.ac.ir/index.php/fid/article/view/702 https://fid.tums.ac.ir/index.php/fid/article/download/702/677

Tehran Universi> Dental Student, Student Research Committee, Babol University of Medical Sciences, Babol, Iran 2016 02 16 2016 08 07 Objectives: This study aimed to assess the effects of two energy drinks on color change (∆E) of two methacrylate-based and a silorane-based composite resin after one week and one month. Materials and Methods: Thirty cubic samples were fabricated from Filtek P90, Filtek Z250 and Filtek Z350XT composite resins. All the specimens were stored in distilled water at 37°C for 24 hours. Baseline color values (L*a*b*) of each specimen were measured using a spectrophotometer according to the CIEL*a*b* color system. Ten randomly selected specimens from each composite were then immersed in the two energy drinks (Hype, Red Bull) and artificial saliva (control) for one week and one month. Color was re-assessed after each storage period and ∆E values were calculated. The data were analyzed using the Kruskal Wallis and Mann–Whitney U tests. Results: Filtek Z250 composite showed the highest ∆E irrespective of the solutions at both time points. After seven days and one month, the lowest ∆E values were observed in Filtek Z350XT and Filtek P90 composites immersed in artificial saliva, respectively. The ∆E values of Filtek Z250 and Z350XT composites induced by Red Bull and Hype energy drinks were not significantly different. Discoloration of Filtek P90 was higher in Red Bull energy drink at both time points. Conclusions: Prolonged immersion time in all three solutions increased ∆E values of all composites. However, the ∆E values were within the clinically acceptable range (<3.3) at both time points.   https://fid.tums.ac.ir/index.php/fid/article/view/1077 https://fid.tums.ac.ir/index.php/fid/article/download/1077/900

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 13 4 2016 12 31 271 278 EN Sara Soheilifar Department of Priodontics, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran Iraj Amiri Professor, Endometrium and Endometriosis Research Center, Hamadan University of Medical Sciences, Hamadan, Iran Mohsen Bidgoli Assistant Professor, Department of Periodontics, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran Morad Hedayatipanah Assistant Professor, Department of Periodontics, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran 2016 03 03 2016 04 25 Objectives: Stem cell (SC) therapy is a promising technique for tissue regeneration. This study aimed to compare the viability and proliferation ability of periodontal ligament stem cells (PDLSCs) isolated from the periodontium of healthy and periodontitis-affected teeth to obtain an autologous, easily accessible source of SCs for tissue regeneration in periodontitis patients. Materials and Methods: The PDLSCs were isolated from the roots of clinically healthy premolars extracted for orthodontic purposes and periodontally involved teeth with hopeless prognosis (with and without phase I periodontal treatment). Cells were cultured and viability and proliferation ability of third passage cells in each group were evaluated using the methyl thiazol tetrazolium assay. The results were statistically analyzed using t-test. Results: No SCs could be obtained from periodontitis-affected teeth without phase I periodontal treatment. The viability of cells was 0.86±0.13 OD/540 in healthy group and 0.4±0.25 OD/540 in periodontitis-affected group (P=0.035). The proliferation ability (population doubling time) of cells obtained from healthy teeth was 4.22±1.23 hours. This value was 2.3±0.35 hours for those obtained from periodontitis-affected teeth (P=0.02). Conclusions: Viability and proliferation ability of cells isolated from the periodontium of healthy teeth were significantly greater than those of cells isolated from the periodontitis-affected teeth.   https://fid.tums.ac.ir/index.php/fid/article/view/1109 https://fid.tums.ac.ir/index.php/fid/article/download/1109/899

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 13 4 2016 12 31 279 286 EN Hoorieh Bashizadeh Fakhar Assistant Professor, Department of Oral and Maxillofacial Radiology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Mysa Mallahi Assistant Professor, Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Golestan University of Medical Sciences, Gorgan, Iran Mehrdad Panjnoush Assistant Professor, Department of Oral and Maxillofacial Radiology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Pooneh Mohseni Kashani Postgraduate Student, Department of Oral and Maxillofacial Radiology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran 2016 05 25 2016 07 13 Objectives: This study aimed to assess the effect of voxel size and object location in the field of view (FOV) on diagnostic accuracy of cone beam computed tomography (CBCT) for detection of simulated bone defects. Materials and Methods: In this in vitro study, bone defects were drilled in four sections of a dry human mandible. Bone blocks were fixed on a platform parallel to the horizontal plane and CBCT images were acquired using 0.2mm and 0.3mm resolutions and five locations of FOV (anterior, posterior, left, right and center). Three reviewers viewed the images twice and the presence or absence of simulated bone defects was determined in positive and negative cases. Results: Sensitivity in different locations of FOV ranged between 0.25-1.0 and 0.75-1.0 in low and high resolutions, respectively. These values were 0.625-1.0 and 0.69-1.0, respectively for specificity. Intra-observer agreements were in the range of 0.84-1.0 and 0.75-1.0 and inter-observer agreements were in the range of 0.3-0.61 and 0.46-0.69 in high and low resolutions, respectively. The highest sensitivity was seen at the center of the FOV and with an increase in resolution from 0.3mm to 0.2mm, the sensitivity increased specially in the posterior region of the FOV while image resolutions and FOV locations did not affect specificity. Conclusions: The highest sensitivity values were obtained at the center of the FOV and lowest values were seen in images acquired in the posterior region in low resolution. Diagnostic accuracy improved with increased resolution. https://fid.tums.ac.ir/index.php/fid/article/view/1263 https://fid.tums.ac.ir/index.php/fid/article/download/1263/902

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 13 4 2016 12 31 287 294 EN Mehrdad Panjnoush Assistant Professor, Head of the Department of Oral and Maxillofacial Radiology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Hamideh Norouzi Dentist, Tehran, Iran Yasaman Kheirandish Assistant Professor, Department of Oral and Maxillofacial Radiology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Ahmadreza Shamshiri Assistant Professor, Department of Community Oral Health, Dental Research Center, Dentistry Research Institute, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Niloufar Mofidi Assistant Professor, Department of Oral and Maxillofacial Radiology, School of Dentistry, Kurdistan University of Medical Sciences, Sanandaj, Iran 2016 07 19 2016 09 16 Objectives: Precise radiographic assessment of the nasopalatine canal is required to prevent implant failure. The purpose of the current study was to determine the three dimensional (3D) morphology, as well as the dimensions of the nasopalatine canal using cone beam computed tomography (CBCT). Materials and Methods: In this descriptive cross-sectional study, maxillary CBCT images from 300 patients (150 men, 150 women) were retrospectively evaluated. Sagittal and coronal views were reviewed to determine the nasopalatine canal morphology and dimensions. The difference in canal dimensions between men and women was evalu