• Korean Journal of Computational Design and Engineering
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• v.7 no.1
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• pp.27-33
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• 2002

MDO(Multidisciplinary Design Optimization) methodology is a new technology to solve a complicate design problem with a large number of design variables and constraints. The design of a dental implant system is a typical complicate problem, and so it requires the MDO methodology. Actually, several analyses such as rigid body dynamic analysis and structural stress analysis etc. should be carried out in the MDO methodology application to the design of a dental implant system. In this paper, as a first step of MDO methodology application to the design of a dental implant system, the impact force which is applied on the tooth in masticating is calculated through the rigid body dynamic analysis of upper and lower jaw-bones. This analysis is done using ADAMS. The impact force calculated through the rigid body dynamic analysis can be used for the structural stress analysis of a dental implant system which is needed for the design of a dental implant system. In addition, the rigid body dynamic analysis results also show that the impact time decreases as the impact force increases, the largest impact force occurs on the front tooth, and the impact force is almost normal to the tooth surface with a slight tangential force.

• Journal of dental hygiene science
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• v.11 no.6
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• pp.553-562
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• 2011

This study was purposed to evaluate the level of occupational stress and the work-related factors of occupational stress in dental hygienists. The study was conducted during the period from May to October 2010 with study population consisted of 316 dental hygienists. The occupational stress was estimated with questionnaire of the Korean Occupational Stress Scale(KOSS) and the work-related factors were consisted with 9 work characteristics. Data analysis was performed with t-test, ANOVA and multiple regression analysis using SPSS(win ver 18.0) program. The level of occupational stress was $52.42{\pm}4.95$ in dental hygienists. The levels of sub-scales for occupational stress were $64.56{\pm}12.17$ in interpersonal conflict, $59.85{\pm}13.59$ in physical environment, $54.60{\pm}13.51$ in organizational system, $52.37{\pm}11.47$ in job demand, $51.71{\pm}10.58$ in lack of reward, $48.14{\pm}12.97$ in insufficient job control, $46.68{\pm}9.25$ in job insecurity, $41.46{\pm}15.98$ in occupational climate, respectively. According to multiple regression analysis, physical burden and daily repetitive working hour were work-related factors of occupational stress in dental hygienists. To conclude, the occupational stress in dental hygienists was higher than mean score of reference values of occupational stress in Korean workers and methods for reducing work load and work hours considering work characteristics of dental hygienist are needed to prevent occupational stress in dental hygienists.

• Journal of Korean society of Dental Hygiene
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• v.14 no.2
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• pp.213-221
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• 2014

Objectives : The purpose of this study is to examine the role function and personality characteristics of mentors on the role stress and organization effectiveness of newly-appointed dental hygienists. Methods : The data were analyzed by the frequency analysis, reliability analysis, validity analysis, and structured equation model(SEM) using AMOS 18.0. The subjects were 214 newly appointed dental hygienists in the hospitals and clinics in Daegu and Gyeongsangbuk-do Province from January to May, 2013. Results : The hypothesis model proved to be appropriate for high validity. A significant results were observed in sociopsychological function and role ambiguity, personality characteristics and role ambiguity, role ambiguity and role conflict, role ambiguity and job satisfaction, role ambiguity and organization commitment, role ambiguity and turnover intention, and career function and organization commitment. Conclusions : It is important to help manage the job-related role stress of newly appointed dental hygienist and increase organizational effectiveness by developing and applying the 'standardized role functions of mentor' which can increase the adaptability of newly appointed dental hygienists.

• Journal of Technologic Dentistry
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• v.31 no.3
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• pp.67-85
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• 2009

This study aims to provide the research for dental technician's stress prevention and management with basic materials by understanding dental technician's psychosocial stress level and examining relevant factors. The subject of this study is 255 dental technologists who work mainly in Seoul Gyeonggi district for a month of April of 2009 and I conducted cross-sectional study through self administered survey. The contents of survey include general feature, occupational feature, health behavior feature. I used Karasek's Job Content Questionnaire, JCQ and Psychosocial well-being index, PWI-SF as means of measurement. To compare the level of dental technician's psychosocial stress, I conducted t-test and ANOVA and I measured the factors that are related with psychosocial stress symptom with step by step multiple regressive analysis. According to the result of Cronbach's a value which is yielded to verify the reliability of means of measurement, the reliability of concept is sufficient. The detailed result of this study is as follows. 1. According to the result of analyzing the stress symptom in accordance with general feature and occupational feature, those dental technologists who are older and not married, graduate from junior college, have lower position, work at university hospital or general hospital show lower stress(p<0.05). There is no difference in the level of psychosocial stress with regard to duty related feature, period of service, daily average working hours, monthly average pay. 2. With regard to health behavior feature, those dental technologists who control weight better and have meal more regularly show lower stress(p<0.05). Those dental technicians who smoke, drink liquid and take a suitable sleep show low stress but the difference does not have significance statistically. 3. With regard to the factors of stress in the workplace, those dental technicians who have lower duty related requirement, have higher duty related control ability, have higher social support, have less instability of employment and have less workload and physical burden show lower stress(p<0.05). 4. According to the result of analyzing the factors that influence dental technologist's stress symptom, social support has the most enormous influence on stress symptom. Unstable employment, regular exercise, regular eating, daily average sleeping hours and technological capacity are also important in this order. According to the result of this study, those dental technicians who have higher social support, less instability of employment, do exercise more regularly, take enough sleep more soundly and have higher technological capacity show lower psychosocial stress symptom. Therefore, to adjust appropriately the dental technician's stress and properly maintain and improve the dental technician's mental health, effective management plan that enables dental technicians to maintain smooth human relationships for dental technicians should be sought. In addition, heath education and health management for dental technicians should be given more thoroughly so that they can establish desirable health behavior in daily life.

• Journal of Korean society of Dental Hygiene
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• v.17 no.1
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• pp.39-47
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• 2017

Objectives: Identifying influencing factors of stress in clinical practice of dental hygiene students through controlling the amount of stress in clinical practice. Methods: A self-reported questionnaire was filled out by 226 dental hygiene students in Daejeon, Cheongju and Jeolla province from March 2 to 30, 2016. The contents of the questionnaire included general characteristics (6 items), clinical practice characteristics (4 items), clinical practice stress (16 items), quality of life (24 items), health promotion behavior (20 items), OHIP (14 items), and critical thinking disposition (15 items). Data was analyzed using SPSS 19.0. for one way ANOVA, scheffe' posthoc test, Pearson correlation coefficients, and multiple regression analysis. Cronbach's alpha of clinical practice stress, quality of life, health promotion behavior, OHIP, and critical thinking disposition were 0.827, 0.913, 0.896, 0.921 and 0.778, respectively. Results: Clinical practice stress was 3.38 points, quality of life was 3.40 points, health promotion behavior was 3.21 points, OHIP was 4.21 points and critical thinking disposition was 3.17 points. Conclusions: Factors that had impact on clinical practice stress include sleeping state, satisfaction of clinical practice, practice number, and the quality of life, and they appeared statistically significant (p<0.05). This exercise showed the necessary manuals and system implementations in clinical practice, which can reduce the amount of stress in dental hygiene students.

• Journal of Korean society of Dental Hygiene
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• v.23 no.6
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• pp.411-421
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• 2023

Objectives: This study aimed to analyze research literature, created over the past 10 years, on occupational stress among domestic dental hygienists and identify the major factors affecting occupational stress. Methods: Of the 192 articles found through literature searches, 26 were selected for the analysis after reviewing titles, abstracts, and full texts. General characteristics of each study, measurement tools employed, and data related to pertinent factors were systematically analyzed. Results: Seven instruments were utilized to measure job stress. Among the variables exhibiting positive correlation with occupational stress, turnover intention was the most prevalent, while variables showing negative correlation were predominantly associated with job satisfaction. Factors influencing occupational stress included emotional labor, workload, organizational social capital, and experiencing verbal abuse. Conclusions: With regard to the most influential factors, "emotional labor" and "turnover intention" had the greatest impacts on job stress and occupational stress, respectively. Based on the findings of this study, follow-up research needs to be conducted to suggest ways to prevent, manage, and reduce occupational stress among dental hygienists

• Journal of Technologic Dentistry
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• v.40 no.4
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• pp.249-259
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• 2018

Purpose: This study aimed to investigate the relationship between dental technology students' life stress and smartphone addiction in order to detect smartphone over-users early, prevent them from getting addicted, and obtain basic data for creating a positive environment for academic achievement by using smartphone in a right way. Methods: The subjects of this study were university students at D University and G University in Daejeon Metropolitan City and Gangwon-do. A questionnaire survey was conducted to the subjects who understood the purpose of this study and participated in it from March 1 to June 10, 2018, and 243 were finally analyzed except 24 questionnaires without sufficient answers. Results: As a result of multiple regression analysis with variables, which were significant in univariate analysis, as independent variables, there were gender and smartphone dependency as general characteristics affecting the degree of smartphone addiction, and family relations and future problems among stress sub-factors were selected as significant variables. Conclusion : In the case of college students, they choose the smartphone as the easiest way to relieve stress because they lack the time and space to actually release stress. Therefore, club activities or on-campus and extra-curricular activities are recommended, and it needs to seek a way to get rid of stress by solving the cause of stress through counseling.

• The Journal of Advanced Prosthodontics
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• v.12 no.6
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• pp.351-360
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• 2020

PURPOSE. The aim of the present study was to compare the stress distributions on the dental implants, abutments, and bone caused by different overdenture attachment types under functional chewing forces. MATERIALS AND METHODS. The 3D finite element models of the mandible, dental implants, attachment types, and prostheses were prepared. In accordance with a conventional dental implant supported overdenture design, the dental implants were positioned at the bone level in the canine teeth region bilaterally. A total of eight models using eight different attachment systems were used in this study. All the models were loaded to simulate chewing forces generated during the centric relationship (450 N), lateral movement (400 N), protrusive movement (400 N), and also in the presence of a food mass unilaterally (200 N). Stress outputs were obtained as the maximum principal stress and the equivalent von-Mises stress. RESULTS. In all attachment types, higher stress values were observed in the abutments, dental implants, and bone in the magnet attachments in different loading conditions. The highest stress values were observed among the magnet systems in the components of the Titanmagnetics model in all loading conditions (stresses were 15.4, 17.7, and 33.1 MPa on abutment, dental implant, and bone, respectively). The lowest stress value was observed in the models of Zest and O-Ring attachments. CONCLUSION. The results of the present study implied that attachment types permitting rotation and tolerating various angles created lower stresses on the bone, dental implants, and abutments.

• Journal of Korean society of Dental Hygiene
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• v.14 no.3
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• pp.381-390
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• 2014

Objectives : The purpose of the study is to investigate the relationship between job-stress and temporomandibular joint(TMJ) disorder in dental hygienists. This study will provide the basic data to improve the working condition and the quality of life. Methods : The subjects were 229 dental hygienists at general hospitals in Seoul, Korea. A self-reported questionnaire was filled out from May 20 to June 20, 2013. The questionnaire consisted of 4 questions of demographic features, 11 questions for TMJ symptoms and 5 questions for job stress. The data were analyzed by frequency analysis, chi-square test, Mann-Whitney U test and multiple job-stress logistic regression analysis using SPSS version 21.0. Results : During the last six months, 53.3%(122 persons) of the dental hygienists had TMJ disorder symptoms including joint noise(40.6%, 93 persons), TMJ pain(31.4%, 71 persons) and limitation of TMJ(21.8%, 50 persons). Job-stress is divided into two ranges including high stress group(4.3-5.0 points) and low stress group(0.0-3.6 points) in TMJ pain and joint noise(p<0.05). TMJ pain was closely related to low back pain, pelvis pain and tension headache arising from the uncomfortable working posture. Conclusions : It is necessary to prevent the job stress in the dental hygienists by the improvement of working condition, emotional stability, and frequent postural change.

• Journal of dental hygiene science
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• v.20 no.3
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• pp.126-135
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• 2020

Background: The purpose of this study is to investigate the effects of entrance exam stress on oral health behaviors and subjective oral health status in female high school students. Methods: A self-reported questionnaire was administered to 216 female high school students in the Gwangju area. We performed an independent t-test, one-way analysis of variance (ANOVA), Pearson's correlation coefficient, and multiple regression analysis using the SPSS/WIN 21.0 program. Results: The average of the entrance exam stress was 2.73, and among the sub-areas, the tension for exam/poor stress was the highest with 3.21. As a result of analysis of general characteristics and subjective oral health status, oral mucosal disease was lower in family income level (p<0.05), bad breath was significantly higher with lower academic performance (p<0.001) and family income level (p<0.05). As a result of oral health behavior and subjective oral health status analysis, dental caries has more than 4 times of caries snacks (per week) (p<0.05), bad breath was found to be more perceived when the average number of daily brushing was 2 or less (p<0.01). Factors affecting subjective oral health status were that dental caries was a patients pressure stress (β=0.202); temporomandibular disorder (β=0.227), xerostomia (β=0.342), and oral mucosal disease (β=0.190) were insufficient spare time; bad breath was academic performance (lower) (β=0.231) and insufficient spare time (β=0.184). There was a statistically significant positive correlation between the subjective oral health status and the subarea of entrance exam stress, excluding future uncertainty stress. Conclusion: It is considered that oral health education should be conducted to prevent oral diseases for students with high parental pressure and insufficient spare time stress as well as finding practical ways to reduce entrance stress.