• 대한통합의학회지
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• 제8권3호
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• pp.53-62
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• 2020

Purpose :Periodontal ligament stem cells maintain tissue homeostasis in periodontal ligament. The purpose of this study was to determine the characteristics of periodontal ligament stem cells isolated from premolar teeth and observe protective effects against oxidative damage caused by Triethylene glycol dimethacrylate (TEGDMA) following treatment with N-acetylsysteine amide (NACA) drug known as enzymatic antioxidants. Methods : Primary periodontal ligament stem cell (PDSC) culture was performed from simply extracted human premolar of orthodontic patients. The characteristics of the primary cultured PDSCs was analyzed using the FACS system. PDSCs was incubated with TEGDMA and NACA. The cell proliferation and survival was determined using WST-1 assay. Collected data were analyzed using SPSS Window 20. Results : Primary cultured PDSCs grow on the floor and develop rapidly in a cluster form from up to 14 days. The morphology of PDSCs showed the spindle-shaped cells and grew directionally. FACS analysis, In addition, positive expression of visible cells were observed in mesenchymal stem cell biomarkers. PDLSCs cell viability was significantly decreased at high concentration in both 3 and 6 hours after TEGDMA treatment. We observed a decrease in the number of cells as well as a morphological change of PDLSCs. Antioxidative effect was notable since the death of PDLSC death was significantly inhibited compared to the control group at 24 and 48 hours after NACA treatment. Conclusion : Therefore, based on the results of this study, further research should be encouraged considering the development of clinical treatment methods using various antioxidants as well as regenerative engineering techniques utilizing periodontal ligament stem cells.

• Journal of Magnetics
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• 제22권2호
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• pp.220-226
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• 2017

SNR (signal to ratio) is a criterion for providing objective information for evaluating the performance of a magnetic resonance imaging device, and is an important measurement standard for evaluating the quality of MR (Magnetic Resonance) image. The purpose of our study is to evaluate the correct SNR measurement for multi-channel coil and parallel imaging. As a result of research, we found that both T1 and T2 weighted images show the narrowest confidence interval of the method recommended by NEMA (The National Electrical manufacturers Association) 1 having a single measurement method, whereas the ACR (American College of Radiology) measurement method using a multi-channel coil and a parallel imaging technique shows the widest confidence interval. There is a significance in that we quantitatively verified the inaccurate problems of a signal to noise ratio using a ACR measurement method when using a multi-channel coil and a parallel imaging technique of which method does not satisfy the preconditions that researchers could overlook.

• 웰빙융합연구
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• 제4권4호
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• pp.1-14
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• 2021

Purpose: This study aims to measure the level of satisfaction with the overall education of current students, who are major consumers of education by department at the Health Care Convergence University, and to establish development strategies such as improving education quality and satisfaction by deriving problems and improvements. Research design, data and methodology: This study drew conclusions through secondary data analysis based on data surveyed by the Educational Performance Management Center of a university in the academic year of 2020. The target of the education consumer satisfaction survey was 470 students of the College in the academic year 2020. Frequency analysis and correlation analysis were applied to the data using the statistical package program SPSS 25 version. Results: In the major curriculum satisfaction survey, the department with the highest score was optics and optics, 4.11, and the department with the lowest score was medical IT, 3.29. Conclusions: The department with the highest correlation in the correlation analysis result of the demand survey by department was the Department of Medical Management and the Department of Medical IT, with a correlation coefficient r=0.984, and the lowest correlation in the correlation analysis result of the demand survey by department was the Department of Medical IT and Dental Hygiene, with a correlation coefficient r= -0.085.

• 대한치과교정학회지
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• 제51권6호
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• pp.397-406
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• 2021

Objective: The purpose of this study was to evaluate the effects of self-ligating brackets (SBs) and other factors that influence orthodontic treatment outcomes. Methods: This two-armed cohort study included consecutively treated patients in a private practice. The patients were asked to choose between SBs and conventional brackets (CBs); if any patient did not have a preference, he or she was randomly allocated to the CB or SB group. All patients were treated using an identical archwire sequence. Evaluated parameters were as follows: treatment duration, number of bracket failures, poor oral hygiene, poor elastic wear, extraction, use of orthodontic mini-implants (OMI), OMI failure, American Board of Orthodontics (ABO) Discrepancy Index (DI), arch length discrepancy, and ABO Cast-Radiograph Evaluation (CRE) score. Stepwise regression analysis was performed to generate the equation for prediction of the CRE. Results: The final sample comprised 134 patients with an average age of 22.73 years. The average DI, CRE, and treatment duration were 21.81, 14.25, and 28.63 months, respectively. Analysis of covariance showed a significant difference in CRE between the CB and SB groups after adjusting for the effects of confounding variables. Stepwise regression analysis using four variables, namely extraction, SB use, poor elastic wear, and additional appliance use, could explain only 25.2% of the variance in the CRE. Conclusions: Although the CRE was significantly better for CBs than for SBs, the clinical significance of this result seems to be limited. Extraction, SB use, poor elastic wear, and additional appliance use may have significant effects on treatment outcomes.

• 한국응급구조학회지
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• 제25권1호
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• pp.177-191
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• 2021

Objectives: This study aimed to combine the satisfaction survey results and suggestion for continuing education of the emergency medical technicians through a systematic review of continuing education of the emergency medical technicians. Methods: This review focused on previous studies published until 2020 that were associated with the continuing education of emergency medical technicians. We followed the guidelines set for each phase of the study and selected the 26 studies that met the selection criteria for the analysis. Results: The level of satisfaction with continuing education for emergency medical technicians was low. The most frequently suggested method for continuing education was patient case presentation. The answers to the desired training subjects of the continuing education program varied. Finally, studies on continuing education have not been published continuously. Conclusion: To enhance the satisfaction and competence of continuing education, we need to provide various programs that reflect the needs of emergency medical technicians attending maintenance training. In addition, various methods should be considered to improve the attendance rate for continuing education, and further investigations and research should be actively conducted on continuing education in the future.

• 한국전자통신학회논문지
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• 제17권6호
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• pp.1213-1220
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• 2022

지난 Covid-19 시기의 비대면 수업을 겪었던 대학생 130명을 대상으로 효율적인 수업만족도 향상을 위한 교육방법의 도출방안에 대해 파악하고자 본 연구를 실시하였다. 수업시간의 적절성, 학습효과 향상, 비대면수업의 계속성, 교육매체의 이용을 수업만족도에 해당되는 항목으로 설정하고 변인간의 차이와 관계성에 대해 파악하여 효율적인 수업만족도 향상을 위한 교육방법의 도출하기 위해 연구를 시도하였다.

• 대한소아치과학회지
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• 제31권1호
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• pp.98-107
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• 2004

적절한 마무리와 연마는 치아 수복물의 심미성과 내구성 향상을 위해 필수적인 과정이다. 본 연구에서는 복합레진의 마무리/연마 과정 시행에 있어서 시기적 차이를 두어 마무리/연마 시기가 복합레진의 표면 거칠기와 경도에 미치는 영향을 비교하고자 하였다. 네 종류의 복합레진(Filtek A110, Silux Plus, Revolution formular2, Palfique Estelite)을 이용하여 시편을 제작하고 마무리/연마 과정을 거치지 않은 대조군과 중합 직후 마무리/연마를 시행한 경우와 1주 후 마무리/연마를 시행한 두 가지 실험군으로 구분하였다. 이 시편들의 표면 거칠기$(R_a\;value,\;{\mu}m)$와 경도(VHN)를 측정하고, 주사전자현미경으로 관찰하여 다음과 같은 결과를 얻었다. 1 네 가지 재료 모두 대조군에서 가장 활택한 표면을 얻었고 마무리/연마 과정을 거친 후 표면 거칠기가 증가하였으나, 마무리/연마시기에 따른 유의한 차이는 보이지 않았다. 2. 표면 거칠기는 중합 직후 마무리/연마를 시행한 경우 Silux Plus와 Revolution formular 2가 차이를 보였고, 1 주 후 시행한 경우 Silux Plus와 Palfique Estelite가 차이를 나타내었다(p<0.05). 3. 경도는 재료에 따라 Palfique Estelite > Filtek A110 > Silux Plus > Revolution formular 2 순으로 감소하였으나, 마무리/연마시기에 따른 차이는 보이지 않았다. 4. 마무리 연마시기가 표면 거칠기와 경도에 미치는 영향은 재료에 따라 차이를 보였다.

• 대한소아치과학회지
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• 제35권4호
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• pp.642-651
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• 2008

본 연구는 2003년 1월부터 2007년 7월까지 전남대학교 병원 소아치과와 응급실에 치아 외상을 주소로 내원한 환자 570명(치아수: 1394개)을 대상으로 연령, 성별분포, 발생원인 및 장소, 손상 받은 치아의 위치 및 유형, 초진시 처치 등에 대한 조사를 통해 외상에 대한 적절한 진단과 치료에 도움이 되고자 시행하였다. 1. 성별에 따른 발생빈도는 1.9:1로 남자의 비율이 높았고, 나이에 따른 발생 빈도는 1세, $6{\sim}8$세, $17{\sim}18$세 때 높았다. 2. 외상의 원인은 유치열과 혼합치열에는 넘어진 경우가 가장 많았으며 영구치열에서는 교통사고와 싸움으로 인한 손상 빈도가 높았다. 외상을 입은 장소는 유치열은 집에서, 혼합치열, 영구치열에는 길에서 비율이 높았다. 3. 외상시 손상 받은 치아의 위치는 유치와 영구치 모두 상악 중절치의 비율이 높았다. 손상의 유형은 유치와 영구치 모두 치주조직의 손상이 많았는데, 유치는 아탈구, 진탕, 함입 순이었으며, 영구치는 아탈구, 진탕, 완전탈구 순이었다. 4. 초진시의 처치는 특별한 처치 없이 경과를 관찰하는 경우가 대부분이었으며, 유치는 33.1%, 영구치에서는 44.5%의 재 내원률을 보였다. 치주조직 손상 후 유치는 20.3%, 영구치는 26.6%의 치수 괴사율을 보였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8183-8189
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• 2014

Background: A comparative cross-sectional study involving oral cancer patients and healthy individuals was designed to investigate associations between retinol, ${\alpha}$-tocopherol and ${\beta}$-carotene with the risk of oral cancer. Materials and Methods: This study included a total of 240 matched cases and controls where subjects were selected from the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). Retinol, ${\alpha}$-tocopherol and ${\beta}$-carotene levels and intake were examined by high-performance liquid chromatography (HPLC) and food frequency questionnaire (FFQ) respectively. Results: It was found that results from the two methods applied did not correlate, so that further analysis was done using the HPLC method utilising blood serum. Serum levels of retinol and ${\alpha}$-tocopherol among cases ($0.177{\pm}0.081$, $1.649{\pm}1.670{\mu}g/ml$) were significantly lower than in controls ($0.264{\pm}0.137$, $3.225{\pm}2.054{\mu}g/ml$) (p<0.005). Although serum level of ${\beta}$-carotene among cases ($0.106{\pm}0.159{\mu}g/ml$) were lower compared to controls ($0.134{\pm}0.131{\mu}g/ml$), statistical significance was not observed. Logistic regression analysis showed that high serum level of retinol (OR=0.501, 95% CI=0.254-0.992, p<0.05) and ${\alpha}$-tocopherol (OR=0.184, 95% CI=0.091-0.370, p<0.05) was significantly related to lower risk of oral cancer, whereas no relationship was observed between ${\beta}$-carotene and oral cancer risk. Conclusions: High serum levels of retinol and ${\alpha}$-tocopherol confer protection against oral cancer risk.

• Journal of Periodontal and Implant Science
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• 제44권2호
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• pp.94-99
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• 2014

Purpose: Various surgical techniques target achieving adequate keratinized tissue around dental implants; however, these techniques are usually performed before implant placement or upon the exposure of submerged implants. The aim of this case report is to describe a simultaneous placement of an interpositional free gingival graft (iFGG) with that of nonsubmerged implants in a patient lacking keratinized tissue and to assess the longterm outcome of this grafted gingiva. Methods: A wedge-shaped free gingnival graft (FGG), including an epithelium-connective tissue (E-C) portion and a connective-tissue-only (CT) portion, was harvested from the palate. The CT portion was inserted under the buccal flap, and the E-C portion was secured tightly around the implants and to the lingual flap. Results: At the 8-year follow-up, the gingival graft remained firmly attached and was well maintained, with no conspicuous shrinkage or reported discomfort during oral hygiene procedures. The use of an iFGG at a nonsubmerged implant placement minimizes the required number of surgical steps and patient discomfort while providing adequate buccal keratinized tissue. Conclusions: Therefore, the technique could be considered an alternative method in increasing the keratinized tissue for cases that have a minimal amount of keratinized tissue.