فهرست مطالب لادن خرمی

Parallel with the progress in the educational technology, teaching methods have shifted from traditional methods to new methods. One of these methods and educational tools, in the electronic education, is educational movies. This study was done to review the effect of educational bisecting periapical radiograph technique video clip on dentistry students’ learning at Isfahan University of Medical Sciences.

In this quasi-experimental study, 54 students of the 6th semester of the dentistry school of Isfahan University of Medical Sciences, who studied the course of dental radiology in the academic years 2017-2018, were included in the study. These students were randomly divided into two groups; in the first group, method of taking radiographs were taught in the field. In the second group, the teaching method was both in the field and by movie. Scores of two groups were compared for evaluate learning of the students. Data analysis was performed using descriptive statistics and independent test.

The mean score of dental radiography in the traditional group was 41±9/06 and in the other group was 105±16.05. The difference between the means of the two groups was significant )p>0/001,t 32.1). The average score of students' satisfaction with the quality of the educational video was 40/3±5/2.

The results showed that educational movie with traditional methods could be an effective strategy for better learning in students.

Digital and film-based radiography are the most common methods of working length determination. The objective of this study was to compare the accuracy of working length determination of curved canals using digital and film-based radiography.

This experimental and interventional study, included forty teethwith curved canals conducted atthe Dentistry Faculty of Isfahan University of Medical Sciences, in 2018. After access cavity preparation, the direct observation method of the apical tip of the file in the root apex determined the actual working length. Teeth were mounted in acrylic blocks. Canal curvature was calculated based on Schneider’s method using software of indirect digital radiography. Images gathered by E-speed film and digital sensors. A pre-curved file was used to measure the working length offilm-based images. In digital radiography, a digital caliper was used to measure the working length with three and six clicks. Data were analyzed by repeated measure analysis, paired t-test, and Intraclass Correlation Coefficient. The Level of significance was set at 0.001.

All groups overestimated the actual length although there weren’t any significant differences (p value > 0.05). Paired t-test didn’t show any significant differences between digital and film-based groups (p value > 0.05).

Considering several advantages of digital radiography over the film-based method, it is the preferred method for working length determination of curved canals.

Due to ever-increasing need for diagnostic radiographs in dentistry, it is necessary to observe techniques to minimize the absorbed patient dose. The aim of this study was the comparative evaluation of inherent visual characteristics such as contrast and density and the gross fog of standard occlusal films with those of occlusal films taken with intensifying screens. In this experimental research, standard occlusal films and occlusal films prepared by cutting extraoral films to the size of occlusal films and placing them between intensifying screens were used. After determination of the most appropriate exposure time and maximum kVp and mA, radiographs were taken from one step wedge and processed using the same condition. A total of 25 radiographs were taken from each of the two film types and then the radiographs underwent densitometry at similar points. In order to evaluate the gross fog, densitometry was carried out at 5 similar points on one unexposed film from each type. Data were analyzed using SPSS 11.5 software and Mann-Whitney test (α = 0.05). Based on the results of this study, the density of the standard occlusal film was more than that of the occlusal film with intensifying screens (p value < 0.001). The contrast of the film with intensifying screens was more than that of the standard occlusal film (p value < 0.001). The gross fog of the film with intensifying screens was less than that of the standard occlusal film (p value = 0.006). Occlusal films with intensifying screens have higher contrast and lower gross fog and density, but in the diagnostic range, in comparison with standard occlusal films; therefore, films with intensifying screens are recommended because they decrease patient absorbed dose by decreasing exposure time.

Occasionally, due to overexposure or over-development, radiographs become dark. If this darkness can be decreased, there will be no need to repeat the radiographs. The aim of this study was to compare the effects of indirect digital technique and lightening solutions on improvement of diagnostic quality of darkened radiographs. In this experimental study, 50 periapical radiographs were taken from different areas of the maxilla and mandible of a head phantom with standard diagnostic quality using the bisecting technique. Subsequently, the exposure time was increased 1.5 times to produce darkened radiographs. The darkened radiographs were corrected by the use of a lightening solution and an indirect digital technique. Three well-trained post-graduate oral radiology students separately assessed the radiographs and graded the radiographs from 1 to 4 using a questionnaire based on their quality. Data were analyzed using Friedman’s and Wilcoxson’s tests (α = 0.05). There were statistically significant differences between diagnostic qualities of darkened radiograph and other groups (p value < 0.001). The qualities of radiographs lightened with lightening solution and indirect digital technique were better than those of the control group (p value < 0.001). The qualities of radiographs lightened with lightening solution were better than those lightened by indirect digital technique (p value < 0.001). Under the limitations of this study in the enhancement of diagnostic quality of dark radiographs, the lightening solution was better than indirect digital technique. Further evaluations are recommended.

Measuring the antero-posterior jaw relationship has an important role in the diagnosis and treatment planning in orthodontics. Common linear and angular measurements to evaluate sagittal jaw relationship, including ANB angle and Wits index are not very accurate because various factors influence them. The aim of this study was to evaluate µ angle range in 6-17 year-old students with normal occlusal relationships in Isfahan. In this descriptive-analytical study, the files in the archives of the Orthodontics Department, Isfahan Faculty of Dentistry, were evaluated and 218 cephalometric radiographs from the files of patients with no orthodontic treatment were selected; the subjects were considered to have normal occlusal relationships based on 13 criteria. The subjects were divided into 5 age groups. After tracing the cephalometric radiographs, ANB angle, Wits index and µ angle (the angle produced by the AB line intersecting the line perpendicular from A to mandibular plane) were measured and the means, standard deviations and changes in the ranges of these angles were determined. Data was analyzed by t-test, ANOVA and Pearson’s and Spearman’s correlation coefficients using SPSS software (α=0.05). The results showed a mean of 17.34 ± 3.74º for β angle with a range of 8-27º. T-test showed significant differences in μ angle between males and females (p value = 0.021). In addition there was no significant relationship between this angle and age (p value > 0.05). There was an inverse and significant relationship between AB angle and Wits index. It was concluded that µ angle is accurate in evaluating antero-posterior jaw relationship and can be used as a valuable index in evaluations.

Measuring the antero-posterior jaw relationship has an important role in the diagnosis and treatment planning in orthodontics. Common linear and angular measurements to evaluate sagittal jaw relationship, including ANB angle and Wits index are not very accurate because various factors influence them. The aim of this study was to evaluate β angle range in 6-17 year-old students with normal occlusal relationships referring to Isfahan Faculty of Dentistry. In this descriptive-analytical study, the files in the archives of the Orthodontics Department, Isfahan Faculty of Dentistry, were evaluated and 235 cephalometric radiographs from the files of patients with no orthodontic treatment were selected; the subjects were considered to have normal occlusal relationships based on 13 criteria. The specimens were divided into 5 age groups. After tracing the cephalometric radiographs, ANB angle, Wits index and β angle (the angle produced by the AB line intersecting the line perpendicular from A to line CB) were measured. Thirty-six specimens were excluded from the study during measurements. Data was analyzed by t-test, ANOVA and Pearson’s correlation coefficient using SPSS software (α = 0.05). The results showed a mean of 31.7 ± 3.31º for β angle with a range of 21.5-39º. No significant differences were observed between males and females. This angle had a direct and significant relationship with age (r = 0.435) and an inverse and significant relationship with AB angle and Wits index. It was concluded that β angle is accurate in evaluating antero-posterior jaw relationship and can be used as a valuable index in evaluations.