correlation between the students' and authorities' ratings for faculty evaluation in Shahid Beheshti School of Dentistry

The most complex type of evaluation is teacher assessment since its measures have low validity and accuracy. To solve the mentioned problem, using a multidimensional approach is suggested. In Shahid Beheshti School of Dentistry, faculty evaluation is performed through 5 sources: undergraduate students, postgraduate students, department chair, education vice chancellor and dean of the school. The present study has been launched to determine the correlation between the students' and managers' ratings for faculty evaluation in academic year of 2010-2011. In this cross sectional study, the questionnaires for faculty evaluation were delivered to the above mentioned 5 groups. Scores of each faculty member were calculated and Pearson coefficient of correlation was used to assess the correlation between the scores of five groups. In order to determine the effect of each group on the final score of teacher assessment, variance component ratio was calculated. Data were analyzed through SPSS software 11.5. The scores allocated to the faculty members by dean of the school showed a significant positive correlation with the education vice chancellor scores [r=0.612]. Correlations between the other groups were not statistically significant. Variance component ratio analysis showed that given the score weights were similar in all groups, postgraduate students had the maximum effect [50.89%] and education vice chancellor had the minimum effect [1.11%] on the variance of faculty evaluation scores. The results of this study showed that among the five evaluating groups, just the opinions of education vice chancellor and dean of the school about faculty members have a significant positive correlation

reliability of post graduate students' ratings for faculty evaluation in Shahid Beheshti dental school in academic year of 2009-2010

Evaluating of academic members on students assessment is a common kind of educational evaluation in most countries such as Iran. Since recognition of the strengths and weaknesses of this evaluation method has an important role in educational promotion, the present study was designed to assess the reliability of post graduate students' in faculty evaluation. This is a descriptive study which is performed on 70 post-graduate students. The faculty evaluation questionnaire, which is routinely used in dental school, consisted of 10 questions with point Likert scale was completed twice by students with one week interval. For intraobserver reliability determination, Weighted kappa and to determine interobserver reliability, generalized Weighted kappa were used. The reliability of total students in all fields was assessed using intra class coefficient. The data were analyzed through SPSS 11.5. Reliability of students in different departments showed no significant statistical difference [p=0.569]. The mean intraobserver reliability was 0.414 and the mean interobserver reliability was 0.297. The results showed that intraobserver reliability in cases were the initial score was best or worst was significantly higher than the cases were the initial score was good or moderate [p=0.034]. The highest intraobserver reliability was in the field of "creating motivation for further study and research" and the lowest reliability belonged to the field of [tolerance to critics and suggestions]. The results of this study showed that the reliability of post graduate students' ratings for faculty evaluation was not high

[ effect ofpost type on stress distribution in endodontically treated maxillary central incisors: a finiie element study]

Following endodontic therapy, teeth need to be protected from fracture. The likelihood of fracture depends on the type of restoration. This simulated study was designed to compare the effect of two different restorations on stress transmission to dental tissue. Four 3-dimentional models of maxillary central incisor were created as following by finite element analysis: [I] Restored with prefabricated stainless steel post, composite core and full ceramic crown [IPS lmpress2], [2] restored with prefabricated Fiber glass post, composite core and full ceramic crown [IFS lmpress2], [3] restored with Accessory Fiber glass post, composite core and full ceramic crown [[PS Impress 2] and [4] without restoration. Each of the models received 100 loads to incisal edge at an angle of 45 degrees to tooth long axis Von Mises Stress analysis was performed for each model, comparing maximum stress intensity observed. In all groups the greatest stress was observed in the cervical region. The stress increased steadily from apex to C.E.J and decreased from C.E.J to incisal edge. The Von Misses Stress in CEJ was highest in Accessory pin group to compared the other groups. Prefabricated stainless steel post, Fiber Glass post and vital tooth groups showed slight differences in CEJ stress. In all groups the greatest stress was observed in the cervical region. It seems the use of Fiber glass posts in weakened anterior teeth acts better than accessory fiber glass post

[Evaluation of microleakage in combined amalgam-composite resin restorations]

Combining the durability of amalgam and the esthetic appearance of composites can improve the quality and longevity of dental restorations. The aim of this study was to evaluate the effect of amalgam etching on microleakage at the cervical margins and the junction between amalgam and composite. In this experimental study 20 extracted sound maxillary premolars were used. Two class II cavities were prepared on the mesial [group A] and distal [group B] surfaces of each tooth. Group A cavities were restored with amalgam on the floor of the cavity and after etching the enamel walls, a self-cure bonding agent was applied followed by composite insertion. The same protocol was followed for group B cavities except that the etchant was placed on both amalgam and enamel walls. The teeth in each group were either stored for 1 week or 6 months in normal saline, then thermocycled for 1000 cycles [2 +/- 4°C and 54 +/- 4°C] and finally immersed in 2% fushin for 1 week. Marginal leakage was assessed by the degree of dye penetration on sections of the restored teeth, under a stereomicroscope [x 10]. Data were analyzed using Mann Whitney U-test [p<0.05]. None of the specimens showed microleakage in the amalgam-composite interface. No statistically significant difference was observed in microleakage between the two groups after 1 week and after 6 months. The study groups did not show a significant difference regarding storage time. Amalgam ethching had no significant effect on the microleakage of combined amalgam-composite restorations