Showing 6 results for Nekoofar
M. Zarabian , M.h. Nekoofar , Bs. Marashi ,
Volume 16, Issue 4 (9 2004)
Abstract
Statement of Problem:Various methods have already been suggested to measure the working length in root canal therapy among which the use of paper point, tactile sense, radiography and electronic apex finder instruments can be named. Investigations on EAL (Electronic Apex Locator) indicate that these instruments can reduce the number of required radiography to a great extent. Moreover, in special cases such as patients with high risk reflex, pregnant women, the mental disabled and handicapped and also in cases with special anatomical structures these instruments are proper substitutes for radiography.
Purpose: The aim of this study was to compare the accuracy of an Iranian made apex finder instrument with Neosono Ultima EZ and radiography.
Materials and Methods: This study was conducted on 51 mandibular molars, devoid of calcification, internal and external resorption, severe root curve or fracture, which were extracted due to periodontal disease or severe caries. All the specimens were washed in 2.5% hypochlorite sodium and washing with water, kept in 10% formalin solution, under room temperature.
Results: The accuracy of the Iranian instrument was measured (81.8%) similar to that of radiography (81.2%). But the accuracy of Neosono Wtima EZ was (92.9%) which was higher than the two other methods.
Conclusion: No statistically significant difference was found between Neosono Ultima EZ instrument and two other groups, using SPSS 10 statistical soft ware.
M. Shahrabi , B. Seraj , Mh. Nekoofar , Sh. Moshrefian , Mj. Kharazi Fard ,
Volume 17, Issue 1 (7 2004)
Abstract
Statement of Problem: Radiography is the most common technique in working length determination, however, because of its limitations is not considered as an ideal technique. Its application, particularly for children due to radiation hazards, technical problems in young and unco-operative children and the superimposition of permanent teeth bud on primary teeth root, lead to numerous problems.
Purpose: The goal of this study was to evaluate the accuracy of an electronic apex locator (EAL) in working length determination of primary teeth.
Materials and Methods: In this in-vitro study 96 canals of the extracted primary teeth, with at least 2/3 of the root length remained, were investigated. There were no obstructed canal, previous root canal therapy and perforation of pulp chamber floor. All working lengths were also measured by radiography. The results of Raypex 4 and radiography were compared with actual root canal lengths determined by direct observation. The applied EAL, in this study was called Raypex 4, a new device belonged to the fourth generation (Ratio Type). The results were analyzed by Chi-Square and Pearson correlation statistical tests.
Results: The accuracy of Raypex and radiography were 61.5% and 63.5%, respectively. The differences between Reypex 4 root canal length measurements and those of direct observation were not significant (P=0.08), but such difference between radiography and direct observation was statistically significant (P=0.01). The diameter of the apical foramen (the site of canal opening) did not affect on Raypex 4 accuray (P>0.05).
Conclusion: Considering the acceptable safetyness, Painlessness, simple and rapid application and an accuracy comparable to that of radiography, the use of Raypex4 EAL for the measurement of primary teeth length is suggested.
M. Tabrizizadeh , N. Nekoofar ,
Volume 18, Issue 4 (5 2006)
Abstract
Background and Aim: Maintaining the original canal path and safety of canal preparation during instrumentation in curved canals have been subjected to many challenges. The aim of this study was to compare several parameters of root canal preparation using flexmaster rotary and hand used Nickel-Titanium instruments.
Materials and Methods: In this experimental study, sixty extracted human teeth with root canal curvatures between 10 and 42 degress were devided into two similar groups with equal mean curvatures. Root canals in one group were prepared using flexmaster rotary instruments and the other with NiTi hand files.After canal preparation, different parameters such as straightening of curved root canal, loss of working length, fracture rate, perforation and working time, were evaluated and compared between the two groups. Data were analyzed by t student test with p<0.05 as the limit of significance.
Results: Results showed that both instruments maintained the original canals' curvature. No loss of working length, instruments fracture or perforation was recorded. Working time was significantly shorter for flexmaster than hand files.
Conclusion: Both systems under investigation respected original root canal curvature and were safe to use. Therefore the rotary techniques could be successfully introduced to undergraduate endodontic programmes.
Ms. Sheikhrezaie, Mh. Nekoofar, K. Oloomi,
Volume 21, Issue 4 (19 2009)
Abstract
Background and Aim: One of the unique properties of MTA is its setting ability in presence of moisture. The sealing ability of MTA used as a root-end filling was shown to be unaffected by the presence of blood, in vitro. It has been recommended that, because of MTA ability to set in the presence of blood, there is no need to dry the perforation site before MTA placement. On the other hand, based on an in vitro study, it is recommended that hemorrhage be controlled at the perforation site and blood be removed from the perforation walls before placement of tooth-colored MTA. Blood contamination may also affect the crystalline structure of MTA. The microhardness of a material is influenced substantially by some fundamental properties of the material such as crystal structure stability. Thus, it can be used as an indicator of the setting process. It can also indicate the effect of various setting conditions on the overall strength of a material. The aim of this study was to evaluate the effect of blood contamination on microhardness of white and gray MTA as an indicator of their setting process.
Materials and Methods: In groups 1 and 2 each material has been mixed with distilled water according to manufacturer,s instruction (No contamination groups). In groups 3 and 4 samples were prepared like groups 1 and 2 but the surface of material placed in contact with blood (Surface blood contamination groups). Samples of groups 5 and 6 were mixed with blood instead of distilled water and also the surfaces of the materials were placed in contact with blood (Mixed with blood groups). All samples were stored in 370C and 100% humidity for 96 hours. The microhardness of the samples was measured with Vickers test.
Results: White MTA samples which have not contaminated with blood had the highest microharness (59.9±11.4 N/mm2) while gray MTA mixed with blood had the lowest hardness (18.45±7.8 N/mm2). One-way ANOVA test showed that contamination with blood significantly reduces the microhardness of both white and gray MTA (p<0.001). The difference between white MTA and gray MTA was significant in groups of no contamination (p<0.001), surface blood contamination (p=0.043), and mixed with blood (p<0.001) according to T-Test analysis. In all of them white MTA had higher hardness than gray MTA.
Conclusion: According to results of our study we recommend that hemorrhage should be controlled and any blood contamination should be removed before placement of both white and gray MTA.
Parisa Noohi, Mohammad Jafar Abdekhodaie, Mohammad Hossein Nekoofar, Prof. Paul Mh Dummer,
Volume 36, Issue 0 (5-2023)
Abstract
Background and Aims: Pulp necrosis in immature teeth disrupts root development and makes the teeth susceptible to fracture. Regenerative endodontics is a relatively new modality of treatment where the necrotic pulp is replaced with newly formed healthy tissue which has normal functionality. Many clinical reports have demonstrated the potential of this strategy to induce root maturation and apical closure. However, clinical outcomes are patient-dependent and unpredictable. Developing predictable protocols can be achieved through the interplay of three basic elements of tissue engineering, namely, scaffolds, stem cells, and signaling molecules. Furthermore, the clinical success of this treatment is influenced by both the method of preparing the inner space of the root and the type of biomaterial utilized in the coronal part. In this review, we discuss recent advances in tissue engineering-based strategies for regeneration of the pulp/dentine complex along with their advantages and limitations.
Mohammad Hossein Nekoofar, Ali Gazni,
Volume 36, Issue 0 (5-2023)
Abstract
Background and Aims: Journal of Dental Research is among the dentistry journal with the highest impact factor. This study aimed to map the most important topics for journal editors and readers.
Materials and Methods: The world's active research topics in the field of dentistry related to the Journal of Dental Research in the last 5 years were extracted from SciMapper's SciTrends. Also, we clustered the most cited papers in that journal to show the most important research topics for the journal editors and readers.
Results: We identified and mapped 11 active international research areas in the field of dentistry and related to this journal. Among 146 faculty members of the school of dentistry, 12 had at least one article related to the most active research areas in the journal. In this regard, they had similar articles elated to the 7 clusters out of 13, but their articles are mainly related to the clusters 7 and 19. Among the investigated faculty members, nine had directly collaborated with 21 authors of the mapped clusters. Moreover, 12 faculty members could also connect to the 126 authors with articles in that journal through their scientific collaborators.
Conclusion: One way to publish in a top international journal is to know the most active and interesting research areas for the journal editors and readers. About 8% of the school of dentistry faculty members at Tehran University of Medical Sciences had some research related to the Journal of Dental Research.
