Dr. MH. Nekoofar

DDS, MSc, DoIBoE, PhD

Author: admin

  • APEC NEWS: Focus on Education

    We are proud that the APEC Education Committee has endeavoured and succeeded in teamwork with Endodontic Associations or Universities such as Tehran University of Medical Sciences, which collaborates to launch our monthly International Journal Club with the invaluable participation of the main author dedicated not only for the members of APEC but also for colleagues joining us from around the globe.Moderating these sessions with his rich background in endodontics, Prof. M H Nekoofar, has created an innovative approach of critical appraisal of the evidence published in high impact endodontic journals.

     abutahun2021 (1).pdf

  • Epinephrine-Entrapped Chitosan Nanoparticles Covered by Gelatin Nanofibers: A Bi-Layer Nano-Biomaterial for Rapid Hemostasis

    Abstract

    Uncontrolled hemorrhage accounts for significant death risk both in trauma and surgery. Various bleeding control techniques have been emerged to augment hemostasis, which still has several limitations and drawbacks. In this study, epinephrine-entrapped chitosan nanoparticles were electrosprayed on a base pad and covered by a gelatin nanofiber layer (E-CS-Gl. Physico-chemical characteristics, hemocompatibility, cytotoxicity, and blood coagulation tests were studied in-vitro, and blood coagulation and hemostasis potential tests were performed in-vivo. The in-vitro results showed that the prepared nano-biomaterial is cytocompatible against HuGu cells. Also, hemocompatibility studies showed that PT and aPTT times did not change in comparison with the controls. Further blood coagulation study indicated that E-CS-Gl provides an ultimate interface to induce red blood cell absorption and aggregation, resulting in augmented blood coagulation. E-CS-Gl also caused rapid clotting in rat models of ruptured femoral artery and liver compared to controls. Findings exhibited that E-CS-Gl is a safe and effective hemostatic agent and provides a new approach for fast and safe hemorrhage control.

    Keywords: Epinephrine, Electrospray, Electrospinning, Hemostasis, Biocompatibility, Chitosan, Nanoparticles.

     Epinephrine-entrapped chitosan nanoparticles covered by gelatin nanofibers A bi-layer nano-biomaterial.pdf

  • Isolation and Differentiation of Adipose-Derived Stem Cells into Odontoblast-Like Cells: A Preliminary In Vitro Study

    Abstract

    Objective: The aim of present study was to isolate and differentiate human adipose-derived stem cells (ASCs) into odontoblast-like cells.

    Materials and methods: In this experimental study, human adipose tissues were taken from the buccal fat pad of three individuals (mean age: 24.6 ± 2.1 years). The tissues were transferred to a laboratory in a sterile culture medium, divided into small pieces and digested by collagenase I (2 mg/mL, 60-90 minutes). ASCs were isolated by passing the cell suspension through cell strainers (70 and 40 μm), followed by incubation at 37ºC and 5% CO2 in Dulbecco’s modified eagle medium (DMEM) supplemented with fetal bovine serum (FBS 5%) and penicillin/streptomycin (P/S). After three passages, the ASCs were harvested. Subsequently, flow cytometry and reverse transcriptase polymerase chain reaction (RT-PCR) were used to detect expression levels of NANOG and OCT4 to evaluate stemness. Then, a differentiation medium that included high-glucose DMEM supplemented with 10% FBS, dexamethasone (10 nM), sodium β-glycerophosphate (5 mM) and ascorbic acid (100 μM) was added. The cells were cultivated for four weeks, and the odontogenic medium was changed every two days. Cell differentiation was evaluated with Alizarin red staining and expressions of collagen I (COL1A1), dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP1).

    Results: The ASCs were effectively and easily isolated. They were negative for CD45 and positive for the CD105 and CD73 markers. The ASCs expressed OCT4 and NANOG. Differentiated cells highly expressed DSPP, COL1A1 and DMP1. Alizarin red staining revealed a positive reaction for calcium deposition.

    Conclusion: ASCs were isolated successfully in high numbers from the buccal fat pad of human volunteers and were differentiated into odontoblast-like cells. These ASCs could be considered a new source of cells for use in regenerative endodontic treatments.

    Keywords: Mesenchymal Stem Cell, Odontoblast, Regenerative Endodontics

     Isolation and Differentiation of Adipose-Derived Stem Cells into Odontoblast-Like Cells A Preliminary In Vitro.pdf

  • PRIASE 2021 Guidelines for Reporting Animal Studies in Endodontology: A Consensus-Based Development

    Abstract

    Animal testing is crucial in situations when research on humans is not allowed because of unknown health risks and ethical concerns. The current project aims to develop reporting guidelines exclusively for animal studies in Endodontology, using an established consensus-based methodology. The guidelines have been named: Preferred Reporting Items for Animal Studies in Endodontology (PRIASE) 2021. Nine individuals (PD, VN, AK, PM, MN, JF, EP, JJ and SJ), including the project leaders (PD, VN) formed a steering committee. The steering committee developed a novel checklist by adapting and integrating their animal testing and peer review experience with the Animals in Research: Reporting In Vivo Experiments (ARRIVE) guidelines and also the Clinical and Laboratory Images in Publications (CLIP) principles. A PRIASE Delphi Group (PDG) and PRIASE Online Meeting Group (POMG) were also formed. Thirty-one PDG members participated in the online Delphi process and achieved consensus on the checklist items and flowchart that were used to formulate the PRIASE guidelines. The novel PRIASE 2021 guidelines were discussed with the POMG on 9 September 2020 via a Zoom online video call attended by 21 individuals from across the globe and seven steering committee members. Following the discussions, the guidelines were modified and then piloted by several authors whilst writing a manuscript involving research on animals. The PRIASE 2021guidelines are a checklist consisting of 11 domains and43 individual items together with a flowchart. The PRIASE 2021 guidelines are focused on improving the methodological principles, reproducibility and quality of animal studies in order to enhance their reliability as well as repeatability to estimate the effects of endodontic treatments and usefulness for guiding future clinical studies on humans.

    Keywords: Animal, Consensus, Endodontics, PRIASE 2021

  • Preparing Hydroxyapatite Nanostructures

    Abstract

    Disclosed herein is a method for preparing hydroxyapatite structures from natural sources such as mammalian teeth and bones. The method may include obtaining a raw powder by grinding raw materials, obtaining a first mixture by mixing the raw powder with one of an alkali metal carbonate and an alkaline earth metal carbonate, and heating the first mixture at a first predetermined temperature for a first predetermined period.

  • Application of Platelet Rich Fibrin in Tissue Engineering: Focus on Bone Regeneration

    Abstract

    Bone tissue engineering (BTE) is a strategy for reconstructing bone lesions, which is rapidly developing in response to higher demands for bone repairing. Recently, this method, along with the emergence of functionally graded, biocompatible and biodegradable materials, has been expanded. Moreover, scaffolds with chemical, physical and external patterns have induced bone regeneration. However, the maintenance of healthy bone and its regeneration in the human body needs a series of complex and accurate processes. Hence, many studies have been accompanied for reconstructing bone by using blood-derived biomaterials, especially platelet-rich fabricates. The most important reason for using platelet-rich formulations in bone regeneration is based on releasing growth factors from alpha granules in platelets, which can induce osteogenesis. Moreover, the presence of fibrin nano-fiber structures as a constituent can provide a good substrate for cell attachments. This study attempts to review the history, structure, and biology of platelet-rich fibrin (PRF) as well as in vitro, pre-clinical, and clinical studies on the use of PRF for bone regeneration.

    Keywords: Biomaterial, Bone Regeneration, Platelet, Platelet-Rich Fibrin, Tissue Engineering

  • PRIASE 2021 Guidelines for Reporting Animal Studies in Endodontology: Explanation and Elaboration

    Abstract

    Laws and ethics require that before conducting human clinical trials, a new material, device or drug may have to undergo testing in animals in order to minimize health risks to humans, unless suitable supporting grandfather data already exist. The Preferred Reporting Items for Animal Studies in Endodontology (PRIASE) 2021 guidelines were developed exclusively for the specialty of Endodontology by integrating and adapting the ARRIVE (Animals in Research: Reporting In Vivo Experiments) guidelines and the Clinical and Laboratory Images in Publications (CLIP) principles using a validated consensus-based methodology. Implementation of the PRIASE 2021 guidelines will reduce potential sources of bias and thus improve the quality, accuracy, reproducibility, completeness and transparency of reports describing animal studies in Endodontology. The PRIASE 2021 guidelines consist of a checklist with 11 domains and 43 individual items and a flowchart. The aim of the current document is to provide an explanation for each item in the PRIASE 2021 checklist and flowchart and is supplemented with examples from the literature in order for readers to understand their significance and to provide usage guidance. A link to the PRIASE 2021 explanation and elaboration document and PRIASE 2021 checklist and flowchart is available on the Preferred Reporting Items for study Designs in Endodontology (PRIDE) website (http://pride-endodonticguidelines.org/priase/).

    Keywords: Animal, Consensus, Endodontics, Healthresearch Reporting Guidelines

     PRIASE 2021 guidelines for reporting animal studies in Endodontology explanation and elaboration.pdf

  • A Cross Analysis of Impact University Ranking System

    Abstract

    First edition of University Impact Ranking (UIR) has been published, and although it’s still in a process of rapid evolution, the result is likely to substantially influence the long-term development of higher education systems across the world based on the United Nations’ Sustainable Development Goals (SDGs). This study aims to analyze  and  critique  the  principal  ranking  system  prepared  by  Times  Higher Education which assess  universities against the  SDGs. This study investigated the reliability of Times Higher Education University Impact Ranking (UIR) and attempted to identify its contribution and impact of participating universities on their societies. Taking an explanatory case study approach, this study used observation, document study, and experts’ reflection as data collection methods. The findings suggest that UIR does not contribute sufficiently to identification of universities that have a good impact on their societies to achieve SDGs.

    Keywords: Times Higher Education, University Impact Ranking, United Nations, Sustainable Development, Cross-Sectional Analysis, Iranian Universities

     A Cross Analysis of Impact University Ranking System.pdf

  • Science Map of Cochrane Systematic Reviews Receiving the Most Altmetric Attention Score: A Network Analysis

    Abstract

    The present study aimed to analyze and visualize the science map of Cochrane systematic reviews (CSRs) with high Altmetric attention score (AAS). On 2020-07-29, the altmetric data of the Cochrane Database of Systematic Reviews were obtained from the Altmetric database (Altmetric LLP, London, UK). Bibliometric data of the top 5% AAS of CSRs were extracted from the Web of Science. Keyword co-occurrence, co-authorship   and   co-citation   network   analyses   were   then   employed   using   VOSviewer software. The random forest model was used to rank the importance of the altmetric resource. A total of 11222 CSRs with AAS were found (Total mentions: 305265), with Twitter being the most popular Altmetric resource. Consequently, the top 5% AAS (649 articles, mean AAS: 204.95, 95% confidence level: 18.95, mean citations:  123.68, 95% confidence level: 13.9) were included. Density mapping revealed female, adult and child as the most popular author keywords. According to network visualization, Helen V. Worthington (University of Manchester, Manchester, UK), the University of Oxford and UK had the greatest impact on the network at the author, organization and country levels respectively. AAS were weekly correlated with citations (rs=0.21) although citations were moderately correlated with policy document and blog mentions (rs=0.46 and rs=0.43). Cochrane systematic reviews received high levels of online attention, particularly in the Twittersphere and mostly from the UK. However, CSRs were rarely publicized and discussed using recently developed academic tools, such as F1000 prime, Publons and PubPeer.

    Keywords: Cochrane systematic review, Altmetric, Bibliometric, Twitter, Machine learning, Network analysis, Random forest

     Science Map of Cochrane Systematic Reviews Receiving the Most Altmetric Attention Score A Network Analysis.pdf

  • The Effect of Operator-Induced Variability on the Physical Properties of ProRoot MTA

    Abstract

    Aims: The aim of this study was to compare the influence of operators on the microhardness and compressive strength of mineral trioxide aggregate (MTA). Materials and Methods: Forty dental specialists were asked to prepare a series of MTA samples. The tested material was ProRoot MTA (DentsplyMaillefer, Switzerland). Each participant prepared one sample to a consistency they considered acceptable for use in practice(improvised group) and another one according to the manufacturer’s recommended water‑to‑powder(WP) ratio(pre‑weighed group). The samples were incubated at 37°C and 95% humidity for 4days. Parameters evaluated in this study were microhardness and compressive strength. Results: Operators mixed MTA samples with varying WP ratios. However, there was no significant difference between the microhardness and compressive strength values of MTA samples between the improvised, the pre‑weighed and the control groups. MTA was mixed in a thicker consistency than the manufacturers recommended ratio (0.33) by 62.5% of the operators. Conclusion: According to the results of this study, even though the WP ratios that were utilized in the clinical setting vary, microhardness and compressive strength values of MTA was not significantly affected.

    Keywords: Compressive Strength, Microhardness, MTA, Surface Microhardness, Water-to-Powder Ratio