The relationship between dental graduate students' MBTI types and academic achievement in problem-based learning / 한국의학교육

PURPOSE: The study aimed to determine the personality types of the graduate students in Seoul National University School of Dentistry (SNU SD) and analyze the specific personal types that were linked to their performance in problem-based learning (PBL). METHODS: A total of 263 graduate students in SNU SD from 2011 to 2013, participated in PBL and completed the Myers-Briggs Type Indicator (MBTI) GS form, which was analyzed statistically to determine whether their MBTI personality types were independent of their PBL performance. In particular, MBTI types were regressed on evaluation subcategories, including tutor evaluation and oral test. RESULTS: ESTJ (20.9%) and ISTJ (18.6%) were the most common MBTI personality types in dental graduate students. Compared with males, female students performed significantly better on the PBL. Judging was the most notable type in PBL performance, with its J-P index being statistically significant. CONCLUSION: PBL is implemented, based on the perspective of student-centered education. Accordingly, the types of personality that usually matriculate in dental school should be monitored, and a student-centered approach to dental education should be adopted.

Change of taste preference and taste bud after unilateral lingual nerve transection in rat

PURPOSE OF STUDY: Lingual nerve damage can be caused by surgery or trauma such as physical irriatation, radiation, chemotherapy, infection and viral infection. Once nerve damage occurred, patients sometimes complain taste change and loss of taste along with serious disturbance of tongue. The purpose of this study was to evaluate the effects of unilateral lingual nerve transection on taste as well as on the maintenance of taste buds. MATERIALS AND METHODS: Male Sprague-Dawley rats weighing 220-250g received unilateral transection of lingual nerve, subjected to the preference test for various taste solutions (0.1M NaCl, 0.1M sucrose, 0.01M QHCl, or 0.01M HCl) with two bottle test paradigm at 2, 4, 6, or 8 weeks after the operation. Tongue was fixed with 8% paraformaldehyde. After fixation, they were observed with scanning electron microscope(JSM-840A(R), JEOL, JAPAN) and counted the number of the dorsal surface of the fungiform papilla for changes of fungiform papilla. And, Fungiform papilla were obtained from coronal sections of the anterior tongue(cryosection). After cryosection, immunostaining with Galpha gust(I-20)(Santa Cruz Biotechnology, USA), PLCbeta2(Q-15)(Santa Cruz Biotechnology, USA), and T1R1(Alpha Diagnostic International, USA) were done. Immunofluorescence of labeled taste bud cells was examined by confocal microscopy(F92-300., Olympus, JAPAN). RESULTS: The preference score for salty and sweet tended to be higher in the operated rats with statistical significance, compared to the sham rats. Fungiform papilla counting were decreased after lingual nerve transaction. In 2 weeks, maximum differences occurred. Gustducin and T1R1 expressions of taste receptor in 2 and 4 weeks were decreased. PLCbeta2 were not expressed in both experimental and control group. CONCLUSION: This study demonstrated that the taste recognition for sweet and salty taste changed by week 2 and 4 after unilateral lingual nerve transection. However, regeneration related taste was occurred in the presence of preserving mesoneurial tissue and the time was 6 weeks. Our results demonstrated that unilateral lingual nerve damage caused morphological and numerical change of fungiform papilla. It should be noted in our study that lingual nerve transection resulted in not only morphological and numerical change but also functional change of fungiform papillae.

Development of microporous calcium phosphate coated nerve conduit for peripheral nerve repair

This study was performed to develop a useful nerve conduit which provides favorable environment for Schwann cell viability and proliferation. Milipore membrane of 0.45um pore size was selected because it permits nutritional inflow from the outside of the conduit and prevents from invading the fibrotic tissue into the conduit. The membrane was rolled and sealed to form a conduit of 2mm diameter and 20mm length. To improve the axonal regeneration and to render better environment for endogenous and exogenous Schwann cell behaviour, the microgeometry and surface of conduit was modified by coating with thin film of calcium phosphate. Cellular viability within the conduit and attachment to its wall were assessed with MTT assay and SEM study. Milipore filter conduit showed significantly higher rate of Schwann cell attachment and viability than the culture dish. However, the reverse was true in case of fibroblast. Coating with thin film of low crystalline calcium phosphate made more favorable environment for both cells with minimal change of pore size. These findings means the porous calcium phosphate coated milipore nerve conduit can provide much favorable environment for endogenous Schwann cell proliferation and exogenous ones, which are filled within the conduit for the more advanced strategy of peripheral nerve regeneration, with potential of reducing fibrotic tissue production.