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Showing 7 results for Kharazi Fard

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.
H. Kermanshah , Mj. Kharazi Fard , H. Yesharim ,
Volume 18, Issue 1 (30 2005)
Abstract

Statement of Problem: Porcelain restorations are susceptible to fracture and a common method for repairing is the use of silane and composite on etched porcelain. Although HF is very effective in porcelain etching but has detrimental effects on tissues.

Purpose: In this study, the effect of APF and PHA was compared with HF in porcelain etching. Also the role of silane, unfilled resin and dentin bonding in bond strength of composite- porcelain was evaluated.

Methods and Materials: In this experimental in-vitro study, one-hundred twenty porcelain square blocks (552 mm) were prepared and bonding surfaces of each sandblasted. Samples were divided into three groups. The first group (n=40) were etched with buffered HF 9.5% (Ultradent) for 1 min., the second group (n=40) were etched with Iranian APF 1.23% (Kimia) for 10 minutes and the third group (n=40) were etched with Iranian PHA 37% (Kimia) for 1 min. Ultradent silane was applied on the surfaces of half of cases in each group. On the surfaces of half of silane-treated samples unfilled resin was applied and dentin bonding was used on the surfaces of the remaining. Samples without silane were treated in a similar manner. Composite cylinder with 4mm diameter and 2 mm height was bonded to porcelain. Specimens were stored in 37°C distilled water for 24 hours and subjected to 500 cycles. Shear bond strength was measured with an Instron machine and type of fracture was evaluated using a stereomicroscope. Results were analyzed using 3 way ANOVA, Kaplan- Maier and Tukey HSD tests.

Results: Findings showed that PHA and APF roughened the porcelain surface without creating retentive micro undercuts but HF etches porcelain and creates retentive microundercuts. Ultradent silane had no significant effect on bond strength of porcelain- composite. Unfilled resin with Ultradent silane compared with dentin bonding with the same silane is more effective in bond strength of composite- porcelain.

Conclusion: Based on present study, application of Ultradent silane on sandblasted and etched porcelain with PHA or APF cannot be used as an alternative to this silane on sandblasted and etched porcelain with HF.


A. Vahid , A. Bahraminia , Mj Kharazi Fard ,
Volume 18, Issue 4 (5 2006)
Abstract

Background and Aim: Determining correct working length in root canal therapy is of great importance in successful treatment. The purpose of this study was to compare the accuracy of two electronic apex locators of fourth generation, Raypex4 and Apit7, in determining working length in vivo.

Materials and Methods: In this test evaluation study performed at Dental School of Tehran University, a total of 32 single canal vital teeth planned for extraction because of orthodontic and prosthetic reasons were selected. Working length determination by each of the two electronic apex locators was performed by two different dentists. These measurements were compared with direct visual measurement after tooth extraction. The dentists working with devices and the endodontist who determined the working length of the extracted teeth as well as the statistician, all were blind regarding the results. The data were compared using binominal distribution test with P<0.05 as the limit of significance.

Results: The accuracy of actual length determination of Raypex4 was 68.8% in the limit of ± 0.5 and 83.3% in the limit of ±1. From the actual length measurements, 75.1% were within the tolerance of +0.5 to-1. The accuracy of the working length determination by Raypex4 was 68.8% within the tolerance of ± 0.5 and 84.3% within the tolerance of ± 1. Taking the tolerance of + 0.5 to -1 mm into account, the accuracy of the instrument was about 78.8%. The accuracy of actual length determination of Apit7 was 65.7% in the limit of ±0.5 and 78.3% in the limit of ±1. Compared to the visual length determination, 78.8% of the actual length measurements were within the tolerance of +0.5 to-1. The accuracy of the working length determination was 62.6% within the tolerance of ±0.5 and 81.3% within the tolerance of ±1. Taking the tolerance of + 0.5 to -1 mm into account, the accuracy of the instrument was about 75.1%.

Conclusion: Raypex4 and Apit7 had similar accuracy in determining the actual length. However, they still can not replace the routine methods of actual length determination.


A. Pakdaman, Y. Soleimani Shayesteh, Mj. Kharazi Fard, R. Kabosi,
Volume 24, Issue 1 (23 2011)
Abstract

Background and Aims: Evaluation is a continuous process which is necessary for improvement of students learning and planning for required changes to obtain the educational objectives. The aim of the present study was to assess students' perspective on the achievement of the educational objectives of the Community Oral Health and Periodontology Departments using the CIPP model of evaluation.
Materials and Methods: A cross-sectional survey has been conducted using a questionnaire consists of four domains as introduced in the CIPP model of evaluation (Context, Input, Process and Product). Two groups of senior dental students of the dental school of Tehran University of Medical Sciences were approached. Data was collected anonymously and was analyzed with non-parametric Mann-Whitney test using the SPSS statistical package.
Results: The response rate was 67.7% for year 6 and 87.5% for the year 5 students. Respondents considered material presented in Periodontology Department more relevant and in need for their future career. However, teaching skills and motivation of the educators in Periodontology Department was considered inadequate. 67% of students reported having problem with material taught in Periodontology Department. Overall, significant difference in domains of Context and Process was observed between two departments (p<0.05). In the output domain students rated their clinical and theoretical ability "weak" in relation to splint, implant, management of acute gingivitis and electrosurgery compared with other topics which rated "good". Students considered their ability in using the principals of Evidence-Based Dentistry moderate.
Conclusion: The evaluation of the educational achievements of the two departments (COH and Periodontics) using CIPP model of evaluation showed that there is significant difference in two domains (Context and Process). In those topics which achievement was reported weak the revision of teaching methods is recommended.
Key Words: Education dental Program evaluation Self-evaluation


Maryam Mohammadi Nodeh, Majid Beshkar, Mohammad Javad Kharazi Fard,
Volume 34, Issue 0 (5-2021)
Abstract

Background and Aims: Fractures of the facial bones and jawbones could cause functional problems along with social and cosmetic problems. Various factors (including road accidents, assault, falling from height, sport injuries, and getting hit by a hard object) could cause these fractures. Collecting and reporting accurate epidemiologic data regarding the facial fractures are major steps toward planning preventive measures. The aim of this study was to collect the epidemiologic data regarding maxillofacial fractures in two referral centers (Shariati and Sina hospitals) in the city of Tehran.
Materials and Methods: The study was a cross-sectional retrospective investigation. All the necessary data were collected from the patients’ files and analyzed using SPSS 25.
Results: The present study pursued data of 454 trauma admitted patients in oral and maxillofacial surgery wards of Shariati and Sina hospitals in 1397 and 1398. These data showed that a number of 374 patients of all patients were men and the other 80 were women. The ratio of male patients to female patients was 4.5:1. In 290 of cases (64%), the fractures occurred as combined fractures and in 164 cases (36%), the fractures occurred as single fracture. These fractures happened mostly in the mandibular bone and in mandibular body, and the least of these fractures happened in Orbit. This study showed that there was a significant relation (with 95% confidence level) between the mandibular body fractures and mandibular angle fractures. This study also showed that there was another significant relation (with 95% confidence level) between the mandibular angle fractures and LeFort 2 fractures. In addition, this study also showed (by using k2 exam) a relation between the etiology of trauma and the number of fractures.
Conclusion: This present study showed that the maxillofacial fractures happened mostly in men much more than women. If we put motorcycle accidents and car accidents in a group together called road accidents, the most common etiology of maxillofacial fractures is road accidents. The results showed that the most fractures happened in the age range of 15-25 year old.
 


Sara Ghadimi, Bahman Seraj, , Mohammad Javad Kharazi Fard, Masoud Kiani, Marzieh Salehi Shahrabi,
Volume 35, Issue 0 (5-2022)
Abstract

Background and Aims: Selecting the appropriate education evaluation method and the effects of this choice according to different fields of medical sciences, is one of the current priorities of medical education. Therefore, the aim of this study was to design a checklist for evaluating the practical skills of dental students and to get compared with the global ranking method.
Materials and Methods: A checklist was developed for the assessment of clinical skills of the practical pediatric course according to an action research method. 32 students were evaluated by the checklist method and 32 students were evaluated by the conventional global rating method (sampling was based on available sample).  Faculty staff and students’ satisfaction regarding the two methods were reported by a 6-scaled measure and statistically analyzed by Wilcoxon Signed Ranks test. The students' scores by the two methods were subjected to paired t test for comparison.
Results: The students were more satisfied with the checklist method (P=0.003). The faculty staff considered a greater ability of the checklist method to differentiate between the students (P=0.03). However, in terms of ease of use and suitability, most faculty staff preferred the traditional method (P=0.02). In other cases, there were no significant differences in the views of students and faculty staff towards the two methods.
Conclusion: In the present study, both Checklist and global rating methods were valuable for evaluation, although due to the greater satisfaction of students and faculty staff with the developed checklist method, the possibility of identifying the weak points leading to decreased scores and better assessment of capabilities, this checklist can be used for evaluation instead.

Hosnie Yusefi Fakhr, Yadollah Soleimani Shayesteh, Afshin Khorsand, Mehrdad Panjnoush, Mohammad Javad Kharazi Fard, Mohadeseh Heidari,
Volume 35, Issue 0 (5-2022)
Abstract

Background and Aims: According to the importance of primary stability on dental implant success and osseointegration, we intend to check and compare the stability and crestal bone loss rate between osteotomy technique and conventional implant insertion techniques.
Materials and Methods: In this study, 26 implants in anterior segment of maxilla in 13 patients were evaluated. The implants were TBR system (Toulouse, France) with 3.5 diameter and 10.5-12 mm length. The implant stability level was recorded immediately after surgery and 3 months later with Ostell mentor. The periapical radiography was taken immediately after surgery, 3 and 6 months to assess crestal bone resorption. Paired t-test and Wilcoxon signed Rank test used for data analysis.
Results: There were no statistically differences between the two treatments techniques in terms of stability (P>0.05). The mean crestal resorption was higher for the osteotomy technique 3 months after implant insertion (P<0.001) but there were no significant differences after 6 months (P=0.678).
Conclusion: Within the limitations of the current study, it can be concluded that the osteotomy it can be considered as a treatment technique in insufficient bone width.


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