Journal of Dental Medicine

Background and Aims: The purpose of the present study was to investigate the relationship between study skills and academic performance of dental students in Tehran University of Medical Sciences.

Materials and Methods: 195 dental students at dental faculty of Tehran University of Medical Sciences in 2013 participated in this descriptive-analytical study. Data were collected using Congos´ Study Skills Inventory including six subscales. Grade Point Average (GPA) indicated their academic performance. Data were analyzed using ANOVA and Tukey test.

Results: The mean score of students’ study skills were 108 out of 200 with standard deviation of 22.06±0.7. Note taking had a significant correlation with GPA (P=0.015).

Conclusion: Since no significant correlation between study skills and academic performance of the students was observed, it seems that there are other dynamics involved in their academic performance which have to be examined.

Background and Aims: Estimating the canal length is essential for reaching to a proper endodontic treatment. Any error and miscalculation in estimation of the working length, especially in curved canals, can result in complication during and after root canal therapy. The introduction of digital radiography has enabled us to measure curved canal length. The purpose of this study was to evaluate the calibration tool of Complementary Metal Oxide Semiconductor (CMOS) digital system in estimation of working length.

Materials and Methods: In this in-vitro study, 80 extracted molar teeth were selected and randomly divided into three groups based on angle and radius of canal curvature. A 5 mm orthodontic wire was placed on the lateral surface of the root. Conventional radiographs were taken after insertion of endodontic file in the apical third of root canals. Radiographic images were scanned and imported to the software of CMOS digital system. Two observers estimated the file lengths with and without using calibration tool of digital measurement software. The correlation between observers was evaluated and then data were analyzed using Paired T-test with 95% confidence.

Results: Overall agreement between observers was good. There was no significant difference between the mean values of calibrated measurement and true file length in the basis of canal curves (P>0.001). However, there was significant difference between the mean values of uncalibrated measurement and true file length in the basis of canal curvature (P<0.001).

Conclusion: The calibrated measurement of file length was more accurate than that of the uncalibrated file length measurement.

Background and Aims: The objective of this study was the development of a checklist for assessment of students’ clinical skills in the clinical oral medicine. The second aim was the assessment of stake holders’ satisfaction of this checklist in comparison to the routine global rating method.

Materials and Methods: The checklist was developed in an expert panel sessions and the validity and reliability of checklist were assessed by CVI and test-retest method, respectively. All students (n=66) were assessed in 2 groups, one with developed checklist and another with global rating. At the end of the session, the satisfaction’s level of staff and students were analysized using Wilcoxon and Mann-Whitney test and the mean scores of students were analysized using Paired T test.

Results: Content validity index (CV I) of checklist was 0.88. Reliability of checklist confirmed with high correlation coefficient (0.9). Staffs’ satisfaction had no significant difference between the two methods
(Wilcoxon P=0.06). The mean score of students who assessed by checklist was higher than global rating with no significant differences (P=0.06).

Conclusion: Regarding the higher students’ satisfaction from checklist and more attention to component of assessment and more objectivity of this method and also higher score in checklist, it seems that the use of a checklist is more proper method for assessing the students’ clinical skills.

Background and Aims: In 1978 WHO (World health organization) formulated a histopathological definition for diagnosis of OLP (oral lichen planus). Previous studies showed that diagnosis of OLP with these criteria are not reproducible. In 2003 Van der Meij et al. represented new clinical and histopathologic definition for diagnosis of OLP known as modified WHO criteria. The purpose of this study was to evaluate the interobserver and intraobserver variability in the histopathological assessment of OLP based on the modified WHO criteria.
Materials and Methods: Fifty five microscopic slides which OLP and OLL (Oral Lichenoid Lesion) were recognized in their clinical differential diagnosis were given to 6 pathologists in two phases with 3 months interval. Each reviewing pathologist was asked to apply the modified WHO definition of OLP and to categorize each case as either OLP, or compatible with OLP. Then, the interobserver and intraobserver variability were assessed by calculation of repeatability coefficient and Kappa statistics.
Results: The results of this study demonstrated that interobserver variability based on modified WHO criteria was 0.77 (strong), while the intraobserver variability varied from 0.58 (moderate) to 0.82 (strong).
Conclusion: In the present study, the interobserver and intraobserver variability in the histopathologic assessment of OLP based on modified WHO criteria was stronger than previous studies which assessed WHO criteria. However, in order to propose the replacement of WHO criteria with modified WHO criteria, further studies with more cases and comparing the two methods is required.

Background and Aims: Nasal obstruction is a common condition among children, in which delaying treatment can stabilize its negative effects on dentoalveolar structures during adulthood. In this study we aimed to investigate the effect of total nasal obstruction on the craniofacial structures of rabbits.
Materials and Methods: In this animal study, total numbers of 44 rabbits with high genetic proximity were selected. Several metal implants were inserted in the anatomic landmarks of their skulls and then underwent three different types of x-ray exposure (lateral, posterior-anterior and occlusal views). Half of them underwent surgically assisted total nasal obstruction, and the other half were considered as control group. All rabbits were kept in the same environment up to maturation period. Then, they underwent the same x-ray exposures. The primary and final radiographs were traced and various linear and angular were compared between them.
Results: The anterior facial height (P=0.01), maxillary depth (P=0.005), articular angle (P=0.005), maxillary and mandibular plan angle were significantly more in the rabbits with total nasal obstruction. However, the interdental width (P=0.005), maxillary perimeter (P=0.005), nasopharyngeal width (P=0.01) and maxillary and mandibular width were significantly less in them. The skull base length (P=0.30), gonial angle (P=0.40), and maxillary length (P=0.10) were not significantly different between the two groups.
Conclusion: Total nasal obstruction had various impacts on the craniofacial structures.

Background and Aims: Due to the very high importance of assessing the clinical performance of students, choosing the best assessment tool and method is one of the most important goals and tasks in medical education. The objective of this study was the development of a checklist for the assessment of dental students’ clinical skills of Tehran University of Medical Sciences, in the clinical complete denture course. The second aim was to determine the validity and reliability of the checklist, and The third aim was the evaluation of raters’ and students’ satisfaction.
Materials and Methods: The checklist was developed in expert panel sessions, and the validity and reliability of the checklist were assessed with CVI (content validity index) test-retest and inter-rater reliability methods, respectively. Students (n=15) were evaluated with a developed checklist. At the end of the session, the satisfaction level of staff and students were assessed. The obtained information was reported descriptively with the expression of mean and standard deviation and in the form of relative and absolute frequencies.
Results: The content validity index (CVI) of the checklist was 0.96. The reliability of the checklist confirmed with a high Intraclass Correlation Coefficient (>0.8) (between 0.82-0.97) (P<0.05). The coefficient of agreement in inter-rater reliability was 0.99 (between 0.991-0.998). Raters’ and students’ satisfaction earned a high percentage of satisfaction.
Conclusion: The designed checklist has the optimal features of a good students’ clinical performance assessment tool; it seems that using this checklist can be an excellent alternative method to a global rating scale to assess the clinical skills of dental students in the complete denture courses.

Background and Aims: Dental caries is a common childhood disease with a considerable effect on quality of life. In visually imparted children oral health and dental treatments are more complicated. To prevent oral diseases, it is necessary to educate visually impaired children. The aim of this study was to evaluate the effects of oral hygiene training on oral health status in visually impaired children.
Materials and Methods: In this semi experimental study, 50 visually impaired children 8 to 12 years old were systematically recruited from visually impaired exceptional schools. Participants were randomly allocated into two control and study groups (25 each). Sillness and Loe plaque index was recorded in all 50 children at baseline and after intervention and follow up periods. The study group received oral hygiene instructions (rolling toothbrush technique) using Braille booklets and hand over hand education. The training repeated three times with two weeks’ intervals and at the end Plaque Index was measured in both groups ANOVA, T-test and Mann Whitney tests were employed to compare intra and inter groups statistical analyses. (α=0.05).
Results: At the baseline, the mean plaque index score in the study group was 2.03±0.52 which decreased to 1.23±0.34 at the end of the intervention (P<0.001). Initially, in control group, the Plaque Index score was 2.26±0.49 which was 2.19±0.44 at the end of the study. Changes in Plaque Index scores were statistically significant between two groups. (P<0.001).
Conclusion: It was concluded that oral hygiene instructions using visually impaired specific training methods improved Plaque Index in these children.

Background and Aims: Dentists faced the highest risk of infection during the COVID-19 pandemic. Educating competent students is the first task of the dental school to overcome the created problems and thus, it is necessary to recognize the created educational deficiencies. This study aimed to assess the students' perspectives from the Dental School at Tehran University of Medical Sciences during the academic year 2019-2020, concerning the competencies expected to be developed during the clinical phase of the general dentistry curriculum during the COVID-19 pandemic. The findings are intended to inform the formulation of educational strategies in the post-pandemic period to address identified gaps in training.
Materials and Methods: During the academic year 2019-2020, a cross-sectional descriptive study was conducted at the School of Dentistry, Tehran University of Medical Sciences, Iran. The study consisted of three phases: checklist design, psychometrics, and a survey of general dentistry students in their third to sixth year. The checklist design phase involved a team of four individuals, including educational officials from the faculty, academic staff members, and medical education experts. Experts confirmed the content validity of the checklist, while reliability was assessed using the Intraclass Correlation Coefficient (ICC), which indicated favorable validity and reliability. Subsequently, questionnaires formatted as Google Forms and a census approach were distributed to all students enrolled in the general dental course within the clinical section of the School of Dentistry at Tehran University of Medical Sciences. Ultimately, following the data collection process, statistical analysis was conducted utilizing descriptive statistics, including the mean and standard deviation, and the findings were communicated to the group managers.
Results: The assessment of content validity was established at a minimum of 71%, based on the evaluations provided by five experts. Additionally, reliability was measured using an intra-cluster correlation coefficient (ICC) exceeding 0.79, signifying a strong level of both validity and reliability. 122 students (53%) in the clinical stage completed the forms related to the pre-clinical/clinical units passed during the Covid era. Despite having enough training, basics Removable Partial Prosthodontics, Surgery 1, and Restorative 3 courses needed more training. In addition, Basics Removable Partial Prosthodontics, Surgery 1, and Surgery 4 needed the most practical training to acquire the necessary competencies.
Conclusion: The findings of this research indicated that the dental students expressed a desire for increased practice across various levels of pre-clinical and clinical courses. This would suggest that the challenges associated with patient interactions during the COVID-19 pandemic may not be the sole contributing factor. Consequently, alongside the need for educational planning to address the requirements of enrolled students, it appears essential to conduct similar studies in the post-pandemic context. Furthermore, this approach may also prove beneficial in evaluating educational needs for ongoing professional development courses.

Background and Aims: Temporomandibular disorders refer to a set of musculoskeletal problems that affect the temporomandibular joint, masticatory muscles, and surrounding anatomical structures. These disorders are associated with symptoms such as pain, click, asymmetry, or reduced maximum opening. The etiology of many temporomandibular disorders is complex, for this reason the initial treatments must be reversible and non-invasive. The use of occlusal splints is effective in reducing symptoms, and therefore, it is recommended in early and even long-term treatment of these disorders. These appliances play major role in developing conditions such as stabilizing joint position, creating favorable occlusal conditions that lead to normal muscle function, and protecting teeth and supporting structures against dental wear. The purpose of this article was to present a comprehensive review of occlusal splints in Persian language. Materials and Methods: A search on Pubmed and Google scholar databases was done and the keywords "occlusal splints" and "temporomandibular disorders" were used. The inclusion criterion was articles published in English in the field of the types of occlusal splint between 1980 and 2020. Conclusion:  In this review, the occlusal splints and their applications have been introduced.The success or failure of treatment with occlusal splints depends on various factors such as the correct selection of patients, the process of manufacturing, occlusal adjustment of splints, and the patients’ cooperation.