M. Eslami , N. Eshghyar , F. Tirgari , G. Rezvani ,
Volume 17, Issue 1 (7 2004)
Abstract
Statement of Problem: Differentiation of dentigerous cyst from unicystic ameloblastoma, discovering any initial ameloblastic changes in lining epithelium of dentigerous cyst at early stage, and differentiation between hyperplastic odontogenic epithelium in fibrous capsule of dentigerous cyst from ameloblastic proliferation, need to an accurate and reliable technique.
Purpose: The aim of this study was to determine and compare Ki-67 immunoreactivity in various locations of the epithelium of Dentigerous cyst and Unicystic Ameloblastoma.
Materials and Methods: In this historical Cohort study, 15 cases of dentigerous cyst and 9 cases of unicystic ameloblastoma were selected. Immunohistochemistry staining was performed by M1B-1 (murine monoclonal antibody against Ki-67). The stained nucleous were counted in basal and suprabasal layer of lining epithelium of both lesions in 3000 epithelial cells. Finally, the percentage of positive cells (presented as labeling index) was calculated, t- student test was used to analyze the related data.
Results: Ki-67 (LI) in basal layer of Dentigerous cyst (2.59±1.66) and Unicystic Ameloblastoma (3.76±79) had no significant differences, but Ki-67 (LI) in suprabasal layer of unicystic ameloblastoma (2.15±0.69) was significantly higher than dentigerous cyst (0.77±0.55) P=0.003).
The difference between the average numbers of positive cells for Ki-67 (LI) in these two lesions was statistically significant (P<0.05) and it was higher in Unicystic Ameloblastoma than Dentigerous cyst.
Conclusion: Based on the findings of this study, it is suggested that Ki-67 (LI) in suprabasal layer or throughout the epithelium can be considered as a useful marker for differential diagnosis between dentigerous cyst and unicystic ameloblastoma.
Shirazian Shiva , Arash Mansourian, Mehdi Vatanpour, Fatemeh Tirgar,
Volume 28, Issue 3 (10-2015)
Abstract
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.
