Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 12 2016 08 15 868 873 EN Leila Khojastepour Department of Oral and Maxillofacial Radiology, School of Dentistry, Shiraz University of Medial Science, Shiraz, Iran Shirin Kolahi Department of Oral and Maxillofacial Radiology, School of Dentistry, Shiraz University of Medial Science, Shiraz, Iran Nazi Panahi Department of Oral and Maxillofacial Radiology, School of Dentistry, Shiraz University of Medial Science, Shiraz, Iran Abdolaziz Haghnegahdar Department of Oral and Maxillofacial Radiology, School of Dentistry, Shiraz University of Medial Science, Shiraz, Iran 2015 11 06 2016 03 09 Objectives: Differential diagnosis of bifid mandibular condyle (BMC) is important, since it may play a role in temporomandibular joint (TMJ) dysfunctions and joint symptoms. In addition, radiographic appearance of BMC may mimic tumors and/or fractures. The aim of this study was to evaluate the prevalence and orientation of BMC based on cone beam computed tomography (CBCT) scans.   Materials and Methods: This cross-sectional study was performed on CBCT scans of paranasal sinuses of 425 patients. In a designated NNT station, all CBCT scans were evaluated in the axial, coronal and sagittal planes to find the frequency of BMC. The condylar head horizontal angulations were also determined in the transverse plane. T-test was used to compare the frequency of BMC between the left and right sides and between males and females. Results: Totally, 309 patients with acceptable visibility of condyles on CBCT scans were entered in the study consisting of 170 (55%) females and 139 (45%) males with a mean age of 39.43±9.7 years. The BMC was detected in 14 cases (4.53%). Differences between males and females, sides and horizontal angulations of condyle of normal and BMC cases were not significant. Conclusion: The prevalence of BMC in the studied population was 4.53%. No significant difference was observed between males and females, sides or horizontal angulations of the involved and uninvolved condyles. https://fid.tums.ac.ir/index.php/fid/article/view/839 https://fid.tums.ac.ir/index.php/fid/article/download/839/848

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 12 2016 08 15 932 935 Shima Aalaei Dental Implant Fellowship, School of Dentistry, Tehran University of Medical Science, Tehran, Iran AND Assistant Professor, Department of Prosthodontics, Qazvin University of Medical Science, School of Dentistry, Qazvin, Iran Abolhassan Abolhassani Fatemeh Nematollahi Elaheh Beyabanaki Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran Amir Ali Mangoli 2016 05 18 Implant-supported craniofacial prostheses are made to restore defective areas in the face and cranium. This clinical report describes a technique for fabrication of an orbital prosthesis with three adjacent implants in the left lateral orbital rim of a 60-year-old woman. Selection of appropriate attachment system (individual magnetic abutments versus bar-clip attachment) for implant-supported orbital prostheses depends upon the position of implants. Bar-magnetic attachment has been selected as the retention mechanism in the present case. https://fid.tums.ac.ir/index.php/fid/article/view/1244 https://fid.tums.ac.ir/index.php/fid/article/download/1244/858

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 12 2016 08 15 874 881 EN Hamid Jalali Assistant Professor, Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Leyla Sadighpour Assoicate Professor, Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Ali Miri Faculty of Dentistry, Tehran University of Medical Sciences Ahmad Shamshiri Dentistry Research Institute, Department of Community Oral Health Faculty of Dentistry, Tehran University of Medical Sciences 2016 01 01 2016 03 11 Objectives: The purpose of this in vitro study was to compare the marginal adaptation and fracture resistance of a zirconia-based all-ceramic restoration with two preparation designs. Materials and Methods: Twenty-four mandibular premolars were randomly divided into two groups (n=12); the conventional group received a peripheral shoulder preparation and the modified group received a buccal shoulder and proximal/lingual chamfer preparation. The marginal fit of the zirconia crowns (Cercon) was evaluated using a stereomicroscope. After cementation, load was applied to the crowns. The mean fracture load and the mean marginal gap for each group were analyzed using t-test (P=0.05). Results: The mean marginal gap was 71±16µm in the conventional group and 80±10µm in the modified group, with no significant difference (P=0.161). The mean fracture strength was 830±153N for the conventional group and 775±125N for the modified group, with no significant difference (P=0.396). All but one fracture occurred in the veneering ceramic. Conclusion: Less aggressive preparation of proximal and lingual finish lines for the preservation of tooth structure in all-ceramic restorations does not adversely affect the marginal adaptation or fracture strength of the final restoration. https://fid.tums.ac.ir/index.php/fid/article/view/985 https://fid.tums.ac.ir/index.php/fid/article/download/985/849

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 12 2016 08 15 882 889 EN Amir Hossein Mirhashemi Assistant Professor, Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran AND Orthodontic Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Mohammad Sadegh Ahmad Akhoundi Professor, Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran AND Orthodontic Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Sedigheh Sheikhzadeh 3Assistant Professor, Orthodontic Department, School of Dentistry, Babol University of Medical Sciences, Babol, Iran Nafiseh Momeni Ahmad reza Dehpour Professor, Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Mojgan Alaeddini Associate Professor, Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran Yasaman Kheirandish Assistant Professor, Department of Oral and Maxillofacial Radiology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Homa Farhadifard Postgraduate Student, Orthodontic Department, Tehran University of Medical Sciences, Tehran, Iran Elahe Ansari 2016 02 21 2016 04 16 Objectives: Fluoxetine is a selective serotonin re-uptake inhibitor (SSRI) widely used for depression, bipolar disorder, anxiety and obsessive-compulsive disorder. The aim of this study was to assess the effect of fluoxetine on orthodontic tooth movement (OTM) in rats. Materials and Methods: Forty-five male Wistar rats were randomly divided into three groups namely the control group (no medication), saline and fluoxetine dissolved in saline. In all groups, nickel titanium closed-coil spring was used between the left maxillary central incisor and first molar to exert 60g force at 2mm activation. Radiographs were taken at one and 21 days. After 21 days, the rats were sacrificed. The distance between the first and second molar teeth, optical density of bone, periodontal ligament (PDL) width, lacuna length and depth and number of osteoclasts were measured and compared among the groups. Results: Tooth movement significantly increased in the fluoxetine group (P=0.005). No significant differences were found in osteoclast count (P=0.069). The PDL width in the mesioapical region of root was significantly different among the groups (P=0.015). Statistical analysis did not show significant differences in depth or length of lacunae in any examined part of the root (P>0.05). Bone densitometry results showed that in fluoxetine group, density of bone in all four areas (alveolar bone, hard palate, skull and mandibular bone) significantly decreased from day one to day 21 (P< 0.05). Conclusion: This study indicated that fluoxetine decreased bone density, which resulted in subsequently greater tooth movement in rats; however, further studies are needed on humans. https://fid.tums.ac.ir/index.php/fid/article/view/1093 https://fid.tums.ac.ir/index.php/fid/article/download/1093/850

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 12 2016 08 15 890 898 EN Narmin Mohammadi Associate Professor, Department of Operative Dentistry, Dental Faculty, Tabriz University of Medical Sciences, Tabriz, Iran Mahmoud Bahari Dental and Periodontal Research Center, Dental Faculty, Medical Sciences University of Tabriz, Iran Soodabeh Kimyai 4Professor, Department of Operative Dentistry, Dental Faculty, Tabriz University of Medical Sciences, Tabriz, Iran Behnam Rahbani Nobar 2015 11 10 2015 12 10 Objectives: Composite repair is a minimally invasive and conservative approach. This study aimed to evaluate the effect of an additional hydrophobic resin layer on the repair shear bond strength of a silorane-based composite repaired with silorane or methacrylate-based composite. Materials and Methods: Sixty bar-shaped composite blocks were fabricated and stored in saline for 72 hours. The surface of the samples were roughened by diamond burs and etched with phosphoric acid; then, they were randomly divided into three groups according to the repairing process: Group 1: Silorane composite-silorane bonding agent-silorane composite; group 2: Silorane composite-silorane bonding agent- hydrophobic resin-silorane composite, and group 3: Silorane composite-silorane bonding agent-hydrophobic resin methacrylate-based composite. Repairing composite blocks measured 2.5×2.5×5mm. After repairing, the samples were stored in saline for 24 hours and thermocycled for 1500 cycles. The repair bond strength was measured at a strain rate of 1mm/min. Twenty additional cylindrical composite blocks (diameter: 2.5mm, height: 6mm) were also fabricated for measuring the cohesive strength of silorane-based composite. The data were analyzed using One-way ANOVA and the post hoc Tukey’s test (α=0.05). Results: Cohesive bond strength of silorane composite was significantly higher than the repair bond strengths in other groups (P<0.001). The repair bond strength of group 3 was significantly higher than that of group 1 (P=0.001). Conclusion: Application of an additional hydrophobic resin layer for repair of silorane-based composite with a methacrylate-based composite enhanced the repair shear bond strength. https://fid.tums.ac.ir/index.php/fid/article/view/848 https://fid.tums.ac.ir/index.php/fid/article/download/848/851

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 12 2016 08 15 899 905 Jaber Yaghini Associate Professor, Torabinejad Dental Research Center, Department of Periodontology, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran Narges Naghsh Assistant Professor, Torabinejad Dental Research Center, Department of Periodontology, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Ira Elaheh Attaei Reza Birang Professor, Torabinejad Dental Research Center, Department of Periodontology, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Ira Ehsan Birang 2016 05 18 Objectives: Scaling and root planing (SRP) is one of the most commonly used procedures during periodontal treatment. The aim of this study was to evaluate the root surface roughness after SRP with erbium: yttrium aluminum garnet (Er:YAG) laser compared to ultrasonic and hand instruments.  Materials and Methods: In this experimental study, 56 extracted sound single-rooted teeth with moderate level of calculus were selected and randomly divided into four groups: SRP was performed with Er:YAG laser (100 mJ pulse, 1W, 10Hz, VSP and contact mode, with 50% water and air) in group one, hand instrument in group two and ultrasonic tool in group three. Group four was considered as the control group. After SRP, all samples were cut by Servocut cutting machine into pieces with 3×3×2mm dimensions. The samples were mounted in acrylic resin. The surface roughness of the samples was evaluated with profilometry, and the data were analyzed using one-way ANOVA and Tukey’s test in SPSS software. Results: Surface roughness was higher in laser and lower in ultrasonic group compared to other groups. There was a significant difference in surface roughness between laser and ultrasonic groups (P=0.043), but there was no significant difference in surface roughness among other groups (P>0.05). Conclusion: The results of this study showed that surface roughness after SRP with Er:YAG laser was not higher than that after manual SRP, but the former value was higher than that after SRP with ultrasonic instrument. https://fid.tums.ac.ir/index.php/fid/article/view/1241 https://fid.tums.ac.ir/index.php/fid/article/download/1241/852

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 12 2016 08 15 906 912 Amir Alireza Rasouli Ghahroudi Ali Homayouni Amir Reza Rokn Professor, Dental Implant Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Periodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Fatemeh Kia Mohammad Javad Kharazifard Afshin Khorsand Associate Professor, Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran AND Department of Periodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran 2016 05 18 Objectivhe cells in culture medium only. Viability of cells was tested in all groups after 24, 48, and 72 hours using the methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay for at least 3 times to obtain reproducible results. Optical density values were read and the data were analyzed using three-way ANOVA and post hoc statistical test.The results showed that cells in G2 had the lowest rate of viability at 24 hours, but the lowest rate of viable cells was recorded in G1 at 48 and 72 hours. The effect of LPS treatment was not statistically significant. Resilon groups showed cell viability values higher than those of gutta percha groups, although statistically non-significant (P=0.105). Cell viability values were lower in gutta percha than Resilon groups when LPS-treated and LPS-untreated groups were compared independently at each time point.It could be concluded that none of the tested root canal filling materials had toxic effects on cultured human monocyte cells whether in presence or absence of LPS contamination. https://fid.tums.ac.ir/index.php/fid/article/view/347 https://fid.tums.ac.ir/index.php/fid/article/download/347/323

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 2 2015 04 15 140 50 Azam Valian Assistant Professor, Department of Restorative Dentistry, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Elham Moravej-Salehi Assistant Professor, Department of Restorative Dentistry, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Allahyar Geramy Professor, Dental Research Center Dentistry Research Institute, Department of Orthodontics, Tehran University of Medical Sciences, Tehran, Iran. Elham Faramarzi Dentist. 2015 10 16 Controversy exists regarding cavity preparation for restoration of interproximal caries in posterior teeth in terms of preserving the tooth structure and suitable stress distribution. This study aimed to assess the effect of extension and type of class II cavities and the remaining tooth structure in maxillary premolars restored with composite resin on the biomechanical properties of teeth using finite element method (FEM).Using FEM, eight three-dimensional (3D) models of class II cavities in maxillary premolars with variable mesiodistal (MD) dimensions, variable thickness of the residual wall in-between the mesial and distal cavities and different locations of the wall were designed. Other dimensions were the same in all models. Cavities were restored with composite resin. A load equal to the masticatory force (200N) was applied to the teeth. Finite element analysis (FEA) was used to calculate the von Mises stress.Stress in the enamel margin increased by increasing the MD dimensions of the cavities. Deviation of the residual wall between the mesial and distal cavities from the tooth center was found to be an important factor in increasing stress concentration in the enamel. Increasing the MD dimensions of the cavity did not cause any increase in stress concentration in dentin.Increasing the MD dimensions of the cavities, decreasing the thickness of the residual wall between the mesial and distal cavities and its deviation from the tooth center can increase stress concentration in the enamel but not in dentin. https://fid.tums.ac.ir/index.php/fid/article/view/345 https://fid.tums.ac.ir/index.php/fid/article/download/345/321

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 2 2015 04 15 151 6 Sara Soheilifar Assistant Profesoor, Department of Periodontics, Faculty of Dentistry, Hamadan University of Medical Science, Hamadan, Iran. Mohsen Bidgoli Assistant Profesoor, Department of Periodontics, Faculty of Dentistry, Hamadan University of Medical Science, Hamadan, Iran. Javad Faradmal Assistant Profesoor, Department of Biostatistics & Epidemiology and Modeling of NoncommuniCable Disease Research Center, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran. Sanaz Soheilifar Assistant Profesoor, Department of Orthodontics, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran. 2015 10 16 It has been claimed that periodontal dressing reduces the risk of wound infection, bleeding and granulation tissue formation and improves tissue healing. This study sought to assess the effect of periodontal dressing on wound healing and patient satisfaction following periodontal flap surgery.This clinical trial was conducted on 33 patients presenting to Hamadan University, School of Dentistry in 2012 whose treatment plan included two periodontal surgical procedures on both quadrants of the maxilla or mandible. The variables evaluated were severity of pain, bleeding, facial swelling and ease of nutrition experienced by patient during the first 3 days after surgery and inflammation, granulation tissue formation and gingival color at 7 and 14 days. Obtained data were analyzed using SPSS version 16.0 and R software and chi-square and t-tests.The mean (±SD) pain score was 1.73±1.153 and 2.79±1.933 in surgical sites with and without periodontal dressing, respectively and this difference was statistically significant (P=0.005). No significant difference was noted between sites with and without periodontal dressing in terms of swelling, bleeding, gingival consistency, granulation tissue formation, gingival color and ease of nutrition (P>0.05).According to the results of the present study, patients did not experience more bleeding, facial swelling or nutritional problems without periodontal dressing; however, the level of pain experienced was lower after surgeries with the use of periodontal dressing. https://fid.tums.ac.ir/index.php/fid/article/view/343 https://fid.tums.ac.ir/index.php/fid/article/download/343/319

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 12 2 2015 04 15 157 62 Anita Munde Professor, Department of Oral Medicine Radiology,Pravara Institute of Medical Sciences, Loni, Maharashtra, India. Priyanka Modi Post Graduate Student, Department of Oral Medicine and Radiology, Rural Dental College, Pravara Institute of Medical Sciences, Loni, Maharashtra, India. Ravindra Karle Professor, Department of Pathology,Rural Medical College,Pravara Institute of MedicalSciences, Loni, Maharashtra, India. Pranali Wankhede Assistant Professor, Department of Oral Medicine and Radiology,Rural Dental College,Pravara Institute of Medical Sciences, Loni, Maharashtra, India. Safia Shoeb Professor, Department of Oral Medicine and Radiology, Rural Dental College,Pravara Institute of Medical Sciences, Loni, Maharashtra, India. 2015 10 16 Central giant cell granuloma (CGCG) is a benign proliferation of fibroblasts and multinucleated giant cells that almost exclusively occurs in the jaws. It commonly occurs in young adults showing a female predilection in the anterior mandible. Multifocal CGCGs in maxillofacial region are very rare and suggestive of systemic diseases such as hyperparathyroidism, an inherited syndrome such as Noonan-like multiple giant cell lesion syndrome or other disorders. Only 10 cases of multifocal CGCGs in the maxillofacial region without any concomitant systemic disease have been reported in the English literature. Here, we report an unusual case of 36 year-old female presented with non-syndromic synchronous, multifocal CGCGs in the left posterior mandible and left posterior maxilla without any concomitant systemic disease. Relevant literature is reviewed and the incidence, clinical features, radiological features, differential diagnosis and management