• 대한치과의사협회지
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• 제54권11호
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• pp.850-864
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• 2016

The Generalized Estimating Equations (GEE) approach is a widely used statistical method for analyzing longitudinal data and clustered data in clinical studies. In dentistry, due to multiple outcomes obtained from one patient, the outcomes produced from an individual patient are correlated with one another. This study focused on the basic ideas of GEE and introduced the types of covariance matrix and working correlation matrix. The quasi-likelihood information criterion (QIC) and quasi-likelihood information criterion approximation ($QIC_u$) were used to select the best working correlation matrix and the best fitting model for the correlated outcomes. The purpose of this study is to show a detailed process for the GEE analysis using SPSS software along with an orthodontic miniscrew example, and to help understand how to use GEE analysis in dental research.

• 대한치과기공학회지
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• 제15권1호
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• pp.63-72
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• 1993

The following results were come out after the careful study on the rational application of dental surveyor in the clinic 1. The adequate path of placement satisfying guiding plane, retention non-interference and esthetics. 2. The location of clasp arm and the accurate under cut position and amount of clasp tip can be judged. 3. In case that the model needs to be mounted to the surveyor, the exactly same location can be attained by the means of the tripoding. 4. The unnecessary undercut areas in the path of placement and removal car be corrected. 5. The surveyor is essential in manufacturing dental prosthesis and it can also carry out all sorts of prospective designs In terms of the diagnosis and treatment.

• 한국광과학회:학술대회논문집
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• 한국광과학회 2005년도 제12회 학술대회 논문초록
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• pp.126-126
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• 2005

• 대한소아치과학회지
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• 제51권1호
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• pp.1-10
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• 2024

Deep learning algorithms are becoming more prevalent in dental research because they are utilized in everyday activities. However, dental researchers and clinicians find it challenging to interpret deep learning studies. This review aimed to provide an overview of the general concept of deep learning and current deep learning research in dental radiographic image analysis. In addition, the process of implementing deep learning research is described. Deep-learning-based algorithmic models perform well in classification, object detection, and segmentation tasks, making it possible to automatically diagnose oral lesions and anatomical structures. The deep learning model can enhance the decision-making process for researchers and clinicians. This review may be useful to dental researchers who are currently evaluating and assessing deep learning studies in the field of dentistry.

• The Journal of Advanced Prosthodontics
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• 제13권6호
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• pp.396-407
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• 2021

PURPOSE. Zirconia has exceptional biocompatibility and good mechanical properties in clinical situations. However, finite element analysis (FEA) studies on the biomechanical stability of two-piece zirconia implant systems are limited. Therefore, the aim of this study was to compare the biomechanical properties of the two-piece zirconia and titanium implants using FEA. MATERIALS AND METHODS. Two groups of finite element (FE) models, the zirconia (Zircon) and titanium (Titan) models, were generated for the exam. Oblique (175 N) and vertical (175 N) loads were applied to the FE model generated for FEA simulation, and the stress levels and distributions were investigated. RESULTS. In oblique loading, von Mises stress values were the highest in the abutment of the Zircon model. The von Mises stress values of the Titan model for the abutment screw and implant fixture were slightly higher than those of the Zircon model. Minimum principal stress in the cortical bone was higher in the Titan model than Zircon model under oblique and vertical loading. Under both vertical and oblique loads, stress concentrations in the implant components and bone occurred in the same area. Because the material itself has high stiffness and elastic modulus, the Zircon model exhibited a higher von Mises stress value in the abutments than the Titan model, but at a level lower than the fracture strength of the material. CONCLUSION. Owing to the good esthetics and stress controllability of the Zircon model, it can be considered for clinical use.

• 한국치위생학회지
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• 제20권1호
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• pp.11-18
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• 2020

Objectives: We analyzed the correlation between physique and size of the dental arch of college students with normal occlusion. Methods: Ninety-nine college students filled out the prepared questionnaire. The length and width of the dental arch of the students was measured using a plaster model after taking an impression. The data were analyzed using the t-test and correlational analysis. Results: The maxilla arch length was 3.70 mm longer and the inter-molar width of the maxilla was 3.06 mm longer in men (both p<0.01) than in women. Additionally, the mandible was 3.66 mm longer in men as compared to those in the women (p<0.01). As height increased, there was increase in the body weight (α=0.683, p<0.01), maxilla arch length (α=0.373, p<0.01), molar width of the maxilla (α=0.214, p<0.05), and the mandible (α=0.280, p<0.01). The greater the weight increase, the greater the maxillary arch length increase (α=0.392, p<0.01), and the greater the molar width of the maxilla (α=0.336, p<0.01) and mandible (α=0.502, p<0.01) increase. Conclusions: As physical size (both height and weight) increased, the maxillary length and molar width also increased. Based on the results of this study, the cause of malocclusion, form and size of the dental arch, and stable occlusion can be used as basic data.

• 한국치위생학회지
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• 제12권3호
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• pp.439-451
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• 2012

Objectives : The goal of this study is to investigate how transformational leadership does affect empowerment, organizational commitment and service quality of dental clinics and hospitals and for their efficient human resources management in a rapidly changing business environment. Methods : For this, workers of a dental clinic and a hospital in Gyeongsangnam-do were selected and the survey was carried out during September 1 to 30 of 2011 and the total 203 questionnaires were analyzed. Results : The analysis of structural model shows that transformational leadership has no significant influence on empowerment but does affect organizational commitment and service quality. And the result also reveals that empowerment has significant effect on organizational commitment and service quality while organizational commitment influences service quality. Conclusion : For this, it is needed that the leader of organization promotes the spirit of his subordinates and helps them find their potential ability and achieve goals by developing various leadership skills to cope with rapidly changing environment of dental clinics and hospitals.

• 보건의료산업학회지
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• 제10권1호
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• pp.79-91
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• 2016

Objectives : The purpose of this study is to suggest an efficient human-resources direction for the management of dental hygienists, the study analyzes the influential relationship between superior's coaching leadership as perceived by dental hygienists and their on the job satisfaction, and proves the moderating effects of leader trust and of followership in the process. Methods : To test the empirical model, data were collected by survey using structural self-administered questionnaires that were distributed to 300 dental hygienists working at dental clinics in the Busan, Ulsan, Gyeongnam, and Gyeonggi areas, from 27 March to 10 April, 2015, 286 cases were used in final analysis. Results : Coaching leadership is found to have a significant influence on job satisfaction. Trust in a leader showed a significant main moderating effect on job satisfaction, on the other hand, followership showed a significant main effect, but no significant moderating effect, on job satisfaction. Conclusions : The results of this study imply that leadership factors such as coaching leadership and leader trust are crucial for improving the job satisfaction of dental hygienists, therefore, a program for enhancing the leadership skills of dental managers is needed in dental health organizations.

• 한국치위생학회지
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• 제10권5호
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• pp.797-805
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• 2010

Objectives : This study was application problem-based learning(PBL) of performance oral health manage in dental hygiene education. and evaluate on learning effect - learning attitude, student assessment(good or bed). Methods : For this study, we sampled 31 dental hygiene students composed of PBL group, Dept of Dental Hygiene, A college. The period of this study was 1 semester(from september, 2008 to December, 2008). To identify the effect of PBL on learning attitudes, student assessment, we used a t-test and compared pre & post effects of PBL using a paired t-test and General Linear Model(GLM), McNemar test. Results : The results of this study that problem based learning(PBL) for dental hygiene students education was more effective in learning process and effect of PBL rather than direct instruction. students assessment results that problem based learning improves their medicine knowledge and communication. Conclusions : This study suggest that PBL contribute to enhancing learning attitudes, learning effect and solve the real problems through self-directed learning.

• 대한치과기공학회지
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• 제42권3호
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• pp.290-297
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• 2020

Purpose: This study aimed at exploring the impacts of organizational conflict and job satisfaction on the turnover intention among dental technicians. Methods: This study utilized a descriptive research design. A structured questionnaire was administered to 159 dental technicians. Of the collected questionnaires, data from 127 valid questionnaires were analyzed using t-tests, analysis of variance, Pearson's correlation coefficient, and hierarchical multiple regression using the IBM SPSS 20.0 statistical package. Results: A positive correlation was identified between organizational conflict and turnover intention (r=0.46, p<0.001); however, a negative correlation was shown between job satisfaction and turnover intention (r=-0.50, p<0.001). A hierarchical multiple-regression model was employed to analyze working hours, unfair treatment from dentists and dental hygienists, organizational conflict, and job satisfaction, which contributed to providing an explanation to 39% of the turnover intention of dental technicians (F=14.16, p<0.001). Furthermore, organizational conflict (β=0.32, p<0.001), job satisfaction (β=-0.31, p=0.003), and working hours (β=0.21, p=0.010) were all shown to affect turnover intention. Conclusion: The impact of the negative consequences of organizational conflict and working hours on the turnover intention should be considered within core strategies for increasing the turnover periods for dental technicians.