Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 16 6 2020 06 24 407 414 EN Ebrahim Yarmohammadi Department of Operative Dentistry, Hamedan University of Medical Sciences, Hamadan, Iran Shahin Kasraei Department of Operative Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran Yasaman Sadeghi Department of Operative Dentistry, Gilan University of Medical Sciences, Rasht, Iran 2018 09 11 2019 12 07 Objectives: It has been reported that bulk-fill composites simplify tooth restoration with no adverse effect on the success rate. This study sought to assess the cuspal deflection of premolars with mesio-occluso-distal (MOD) cavities restored with bulk-fill and conventional posterior composite resins. Materials and Methods: This in-vitro experimental study was conducted on 64 human maxillary premolars. MOD cavities were prepared on teeth and restored with Filtek P60 conventional composite and Filtek Bulk Fill flowable, X-tra fill, and X-tra base bulk-fill composites in four groups (n=16). Distance between the cusp tips was measured before, five minutes, 24 hours, 48 hours, and one week after restoration. The data were analyzed using repeated-measures analysis of variance (ANOVA) and Tukey’s test (α=0.05). Results: The mean±standard deviation (SD) of cuspal deflection at five minutes after the restoration was 13.5±5.3, 12.2±3.5, 11.3±4.4, and 10.4±3.7 µm for Filtek P60, Filtek Bulk Fill, X-tra fill, and X-tra base, respectively. ANOVA showed that bulk-fill composites did not cause a significant reduction in cuspal deflection compared to P60 (P>0.05). Cuspal deflection in all groups significantly decreased with time (P<0.05). Conclusion: Bulk-fill composites have no superiority over P60 in the reduction of cuspal deflection. The cuspal deflection was variable at different time points in all groups and decreased over time. https://fid.tums.ac.ir/index.php/fid/article/view/2804 https://fid.tums.ac.ir/index.php/fid/article/download/2804/1783

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 16 6 2020 06 24 473 477 Hassan Mirmohammadsadeghi Department of Oral and Maxillofacial Surgery, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran Farzad Aghdashi Department of Oral and Maxillofacial Surgery, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran Golnaz Nahvi Department of Orthodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran Mohammad Esmaeelinejad Department of Oral and Maxillofacial Surgery, Dental School, Semnan University of Medical Sciences, Semnan, Iran 2019 07 16 2019 12 01 Mandibular defects due to surgical resection of pathologies are common challenges for maxillofacial surgeons. In some clinical situations, alteration or combination of different surgical procedures is needed to reduce the size of bony defects and improve the success rate of bone grafts. In the current study, an 18-year-old female with a pathological lesion (ameloblastoma) in the mandible is presented. After tumor resection, bony defect reconstruction with autogenous bone graft was combined with a mandibular setback to facilitate the procedure. In this case, the simultaneous combination of orthognathic mandibular setback movement with tumor resection in a single surgical session helped to reduce the bony defect size. The adoption of this approach led to a decrease in the volume of graft harvesting and improved the success rate of the grafting procedure. https://fid.tums.ac.ir/index.php/fid/article/view/3232 https://fid.tums.ac.ir/index.php/fid/article/download/3232/1791

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 16 6 2020 06 24 415 420 EN Behnoosh Jalalian Department of Restorative Dentistry, Faculty of Dentistry, Qom University of Medical Sciences, Qom, Iran Parisa Golkar Dental Materials Research Center, Department of Operative Dentistry, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran Alireza Paktinat Private Practice, Tehran, Iran Elham Ahmadi Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran Seyed Ali Panahande Department of Restorative Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Ladan Ranjbar Omrani Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran AND Department of Restorative Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran 2018 07 04 2018 10 19 Objectives: Hydroxyapatite (HA) nanoparticles are used to improve the physical and mechanical properties of glass ionomers (GIs). This study aimed to assess the effect of addition of different weight percentages of nano-HA on degree of conversion (DC) of Fuji II LC GI cement using a spectrometer. Materials and Methods: In this in vitro experimental study, 30 samples were fabricated of Fuji II LC (improved) GI cement in six groups (n=5) containing 0%, 1%, 2%, 5%, 7% and 10wt% nano-HA. The obtained paste in each group was subjected to Fourier-transform infrared spectroscopy (FTIR) before curing to assess the monomer to polymer DC percentage. The paste was then light-cured and underwent FTIR again. One-way ANOVA was applied to compare the DC percentage of different groups. Pairwise comparisons were performed using the Tukey’s test. Results: The DC was 57.88±0.57% in 0%, 60.04±0.63% in 1%, 66.92±0.54% in 2%, 65.5±0.71% in 5%, 51.49±0.24% in 7% and 50.09±0.32% in 10% nano-HA group. The difference in DC among the groups was statistically significant (P<0.0001). The highest DC was noted in 2% nano-HA and the lowest DC was found in 10% nano-HA group. Pairwise comparisons revealed significant differences between the groups in DC (P<0.0001). Conclusion: Increasing the weight percentage of nano-HA to 2% increased the DC but increasing the nano-HA weight percentage over 5% decreased the DC of resin-modified glass ionomer cement (RMGIC). The highest DC was noted in 5w% and 2w% nano-HA groups. Thus, 5w% and 2w% nano-HA can be used to improve the DC of RMGIC. https://fid.tums.ac.ir/index.php/fid/article/view/2685 https://fid.tums.ac.ir/index.php/fid/article/download/2685/1784

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 16 6 2020 06 24 478 483 Fatima Balaghi Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran. AND Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Mahya Hasanzade Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran. AND Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Hamid Mahmood Hashemi Department of Oral and Maxillofacial Surgery, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Simindokht Zarati Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran. AND Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran 2018 09 28 2019 08 21 The present clinical report describes the fabrication of an implant-retained prosthesis with bar and clip retention for a patient with total rhinectomy due to basal cell carcinoma (BCC). The nasal prosthesis was retained on the face by a reverse Y-shaped bar with horizontal and vertical extensions, resulting in favorable retention and function. https://fid.tums.ac.ir/index.php/fid/article/view/2849 https://fid.tums.ac.ir/index.php/fid/article/download/2849/1794

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 16 6 2020 06 24 421 428 Bahman Seraj Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran Ghasem Meighani Department of Pediatric Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Shabnam Milani Department of Pediatric Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Mostafa Fatemi Department of Dental Biomaterials, Shahid Beheshti University of Medical Sciences, Tehran, Iran 2019 04 30 2020 02 12 Objectives: Considering the importance of timesaving in pediatric dentistry, if the efficacy is achieved along with shorter working time and less technical sensitivity, the behavior management of young patients can be anticipated. This study aimed to compare the effect of precuring and postcuring of total-etch and self-etch bonding agents on the microleakage of sealants. Materials and Methods: This study was conducted on forty impacted third molars, which were surgically extracted. The samples were divided into five groups: 1. Control (etching and sealant), 2. Precured fifth-generation bonding agent (Adper Single Bond 2) and fissure sealant, 3. Postcured fifth-generation bonding agent (Adper Single Bond 2) and fissure sealant, 4. Precured seventh-generation bonding agent (Single Bond Universal) and fissure sealant, and 5. Postcured seventh-generation bonding agent (Single Bond Universal) and fissure sealant. All specimens were thermocycled (×1000), immersed in 0.5% basic fuchsine solution for 24 hours, sectioned, digitally photographed, and measured using the LAS EZ program. The data were analyzed using Kruskal-Wallis and Dunn’s tests. Results: Leakage in the control group and the third group was significantly lower than that in other groups. In pairwise comparisons, a significant difference was found between the control group and the fifth group and between the third group and the fifth group. Conclusion: The conventional method of sealant placement showed superior results in comparison with the use of an intermediate layer of the bonding agent. https://fid.tums.ac.ir/index.php/fid/article/view/3123 https://fid.tums.ac.ir/index.php/fid/article/download/3123/1785

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 16 6 2020 06 24 429 435 Arash Dabbaghi Department of Oral and Maxillofacial Radiology, School of Dental Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Sanaz Sharifi Department of Oral and Maxillofacial Radiology, School of Dental Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Masoud Esmaeili Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran 2018 10 08 2019 07 31 Objectives: Cone-beam computed tomography (CBCT) is used in diagnostic situations, as well as tooth impaction and its complications. A possible sequela of tooth impaction is resorption of adjacent teeth, complicating the treatment plans. This study aimed to determine the diagnostic accuracy of high- and low-resolution CBCT scans in the detection of external root resorptions (ERRs), caused by an adjacent impacted tooth in the cementoenamel junction (CEJ), mid-root, and apical areas. Materials and Methods: Forty-five intact single-rooted teeth were divided into three groups of 15. Each group was dedicated to each zone of the root. Slight, moderate, and severe ERRs were formed, and CBCT scans were taken before and after the formation of ERRs. The diagnostic accuracy was assessed, and the Proportion test was used to compare the results. Results: The statistical analyses of high- and low-resolution images showed a significant difference (P<0.05), which implies the higher accuracy of high-resolution images. The highest diagnostic accuracy among different zones was related to the mid-root, and the lowest was related to the apical zone. In terms of the size of ERRs, the diagnostic accuracy was the lowest for slight ERRs. Conclusion: The most reliable and accurate diagnostic mode was found in high-resolution images, in the mid-root zone, and with severe ERRs. The lowest diagnostic accuracy was found in low-resolution images, in the apical zone, and with slight ERRs. https://fid.tums.ac.ir/index.php/fid/article/view/2870 https://fid.tums.ac.ir/index.php/fid/article/download/2870/1786

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 16 6 2020 06 24 436 449 EN Koduri Sridevi Department of Oral Medicine and Radiology, Lenora Institute of Dental Sciences, Rajahmundry, Andhra Pradesh, India Saka Malathi Department of Oral Medicine and Radiology, Army College of Dental Sciences, Secunderabad, Telangana, India Chalapathi KV Department of Oral Pathology and Microbiology, Care Dental College and Hospital, Guntur, Andhra Pradesh, India Chowdary Nagarjuna G Department of Pedodontics and Preventive Dentistry, MNR Dental College and Hospital, Sangareddy, Telangana, India M Gayathri Department of Oral Medicine and Radiology, Adhiparasakthi Dental College and Hospital, Melmaruvathur, Tamilnadu, India G Eswar Chand Medical Graduate, Mamata Medical College, Khammam, Telangana, India Abhishek Nayyar Department of Oral Medicine and Radiology, Saraswati Dhanwantari Dental College and Hospital and Post-graduate Research Institute, Parbhani, Maharashtra, India 2018 01 06 2018 07 20 Objectives: The present study aimed to evaluate CD4 cell counts, lipid profile, and oral manifestations in human immunodeficiency virus (HIV)-infected and acquired immune deficiency syndrome (AIDS) patients and their correlation with seronegative controls. Materials and Methods: In this cross-sectional, hospital-based study, there were three groups of subjects: group A consisting of 500 healthy patients (controls), group B composed of 500 HIV-infected patients, and group C comprised of 500 AIDS patients based on their CD4 cell counts. CD4 cell counts were assessed using the CyFlow counter. Lipid the pattern of root fracture (P=0.39). However, site and extent of fractures were significantly different among the groups (P<0.05). Conclusion: The conventional cements provided optimal retention and caused less root damage after post removal. Thus, cements providing adequate retention and allowing easier post removal are recommended for use in endodontically treated teeth with a possibility of requiring retreatment.   https://fid.tums.ac.ir/index.php/fid/article/view/3707

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 18 0 2021 10 18 3653 3653 Shirin Sakhdari Department of Oral & Maxillofacial Radiology, Islamic Azad University, Faculty of Dentistry, Tehran, Iran Sara Farahani Dentist, Private Practice, Tehran, Iran Ehsan Asnaashari Department of Endodontics, Islamic Azad University, Faculty of Dentistry, Tehran, Iran Sahel Marjani Department of Oral & Maxillofacial Radiology, Islamic Azad University, Faculty of Dentistry, Tehran, Iran 2020 07 01 2020 10 14 Objective: This study sought to assess the frequency and severity of second molar external root resorption (ERR) due to the adjacent third molar and its correlation with the position of third molar and other related factors using cone-beam computed tomography (CBCT). Materials and Methods: This cross-sectional study evaluated 320 second molars and their adjacent impacted third molars on CBCT scans of patients over 16 years, retrieved from the archives of Azad University Radiology Department. Presence/absence of second molar ERR, its location and severity (if present), and position of adjacent third molar were determined on CBCT scans, and recorded in a checklist. Data were analyzed using a logistic regression model. Results: The frequency of second molar ERR was 33.4% in the mandible and 14% in the maxilla. The severity of ERR was significantly correlated with the involved jaw (P=0.001) but had no correlation with age, gender, or depth of impaction of adjacent third molar (P>0.05). The mesioangular and horizontal positions of impacted third molars had a significant correlation with the frequency of second molar ERR (P<0.006). Conclusion: According to the results of this study, ERR occurring in second molars adjacent to third molars is common, especially in the mandible. Mesially inclined third molars have a greater potential of being associated with ERR in second molars.   https://fid.tums.ac.ir/index.php/fid/article/view/3653

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 18 0 2021 09 29 3755 3755 Vajihe Barati Department of Pediatric Dentistry, Faculty of Dentistry Mashhad University of Medical Sciences, Mashhad, Iran Maryam Mehrabkhani Department of Pediatric Dentistry, Faculty of Dentistry Mashhad University of Medical Sciences, Mashhad, Iran Iman Parisay Department of Pediatric Dentistry, Faculty of Dentistry Mashhad University of Medical Sciences, Mashhad, Iran Niayesh Mastoori Private Practice, Mashhad, Iran 2020 09 01 2021 06 08 Objectives: This study aimed to assess the effect of casein phosphopeptide amorphous calcium phosphate (CPP-ACP) and xylitol chewing gums, and probiotic yogurt, as chemical plaque control strategies, on periodontal parameters. Materials and Methods: This randomized clinical trial evaluated 120 eligible dental students that were randomly divided into four groups (n=30) for use of (I) CPP-ACP chewing gum, (II) xylitol chewing gum, (III) probiotic yogurt, and (IV) chlorhexidine (CHX) mouthwash. The oral hygiene index-simplified (OHI-S), Silness and Loe gingival index (GI), and Silness and Loe modified plaque index (PI) were measured before and on days 15 and 30 after using the products. Paired t-test or its non-parametric equivalent was used to analyze the parameters after the intervention compared with baseline. The study groups were compared using one-way ANOVA or its non-parametric equivalent. Results: The OHI-S did not change over time, and most participants had a good OHI-S. The CHX group had the most favorable, and the probiotic yogurt group had the least favorable GI. Pairwise comparisons of the groups did not reveal a significant difference in GI between the CPP-ACP gum and CHX groups (P>0.05). CHX caused the greatest improvement in PI, with significant differences with other groups. Conclusion: CHX was the most effective for improvement of periodontal parameters followed by CPP-ACP, which showed better results compared with other groups.   https://fid.tums.ac.ir/index.php/fid/article/view/3755

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 18 0 2021 09 29 3550 3550 Mahdi Niknami Department of Oral and Maxillofacial Radiology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran Elham Emami Department of Oral and Maxillofacial Radiology, School of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Abdolhosein Mozaffari Private Practice, Tehran, Iran Hashem Sharifian Department of Radiology, Amir A'lam Hospital, Tehran University of Medical Sciences, Tehran, Iran Sanaz Safari Department of Oral and Maxillofacial Radiology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran 2020 04 22 2020 12 12 Objectives: This study aimed to evaluate the correlation between the opacification degree of the paranasal sinuses on computed tomography (CT) with clinical symptoms, and anatomical variations of the nose and paranasal sinuses in patients with chronic rhinosinusitis (CRS). Materials and Methods: This descriptive prospective study evaluated 100 patients (60 males and 40 females), who were diagnosed with CRS by ENT specialists according to the clinical findings, and were scheduled for a CT scan. The patients were requested to express the severity of their symptoms using a visual analog scale. The CT scans of the paranasal sinuses were assessed for the presence of anatomical variations and scored using the modified Lund-Mackay scoring system for the opacification degree of each sinus. The correlations between the anatomical variations and sinusitis, and also between the severity of symptoms/disease severity and CT scores were statistically analyzed. P<0.05 was considered statistically significant. Results: The most common symptoms were purulent (discolored) nasal drainage and nasal obstruction. Septal deviation was the most common anatomical variation. The maxillary and anterior ethmoid sinuses were the most commonly involved areas. The Spearman’s correlation coefficient showed a significant correlation between the sinus involvement and some of the evaluated symptoms, as well as certain types of anatomical variations (P<0.05). Conclusion: Some specific anatomical variations of the paranasal sinuses may predispose them to sinusitis. The CT scan score can predict the severity of many symptoms such as purulent (discolored) nasal drainage, nasal obstruction, hyposmia/anosmia, halitosis, cough, and fatigue, among the other symptoms of CRS. https://fid.tums.ac.ir/index.php/fid/article/view/3550

Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 18 0 2021 09 08 3480 3480 Mahsa Mohajeri Department of Prosthodontics, School of Dentistry, Tehran University of Me