• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.05a
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• pp.255-258
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• 2002

Dental chewing masticator, which is an essential device for evaluating the wear of dental resin and the interfacial failure between the filling resin and enamel of tooth used in conservative dentistry, was developed. This dental chewing masticator mimics the chewing motion and loading by adapting DC motor and rotary cam system. Chewing loading of 49N was imposed by computer-displacement control, loadcell, LM guide, and spring system. Extracted tooth was fixed into a holding jig, and this jig was mounted with rubber pad on the $15^{\circ}$inclined surface to consider the lateral movement of periodontal ligament. A water bath was installed for providing the environment of inside mouth and for circulating the $5^{\circ}C-55^{\circ}C$ water to evaluate the effect of hydrothermal cycling on the damage of resin filled teeth during long-term chewing activity.

• International Journal of Oral Biology
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• v.41 no.2
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• pp.75-81
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• 2016

Human mouth environment is known to include a variety bacteria, including Streptococcus spp., Staphylococcus spp., Actinomyces spp., Lactobacillus spp., Candida spp., Enterobacteriaceae, et al. Human oral microorganisms can cause dental caries, gingivitis, periodontitis, respiratory tract infection, and cardiovascular disease. Thus, right denture cleaning is essential to oral and general human health. The aim of this study was to evaluate the bactericidal effect of a sodium dichloroisocyanurate-based effervescent tablet (Aos Denti Germ, Aos Company, Chungbuk, Korea) against oral microorganisms. A total of 5 species Streptococcus spp. (Streptococcus anginosus, Streptococcus mitis, Streptococcus mutans, Streptococcus oralis, and Streptococcus sobrinus), Actinomyces oris, Candida albicans, and Escherichia coli were used in this study. All strains were exposed to the distilled water prepared with effervescent tablet. After the exposure, the mixture of strains and effervescent tablet was inoculated onto blood agar or MacConkey agar plate and cultured at $36^{\circ}C$. All strains were killed immediately on exposure to effervescent tablet. The results suggested that effervescent tablet could be used as an effective denture cleanser for dental hygiene.

• Journal of Korean society of Dental Hygiene
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• v.16 no.1
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• pp.53-59
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• 2016

Objectives: The purposes of this study is to examine the relationship between emotional labor and burnout among dental hygienists. Methods: A self-reported questionnaire was completed by 247 dental hygienists from September 4 to October 9, 2014. The questionnaire consisted of emotional labor, job burnout, and job stress. Emotional labor included frequency of emotional expression, compliance with emotional regulation, emotional diversity, and emotional dissonance by the instrument pf Morris and Feldman. Job burnout was adopted from Maslach burnout inventory(MBI). Job stress was adpoted from instrument of Chang. Except 13 incomplete answers, 234 data were analyzed by AMOS 18.0 and SPSS 18.0 program. Results: The emotional labor has a significant positive relation to the job burnout. There was a statistical significance between emotional labor and job stress. Job stress had a positive relation to job burnout. Job stress had a mediating effect between emotional labor and job burnout. Emotional labor had a direct effect on the job burnout. Job stress also had a mediating effect on job burnout. Conclusions: It is necessary to improve working environment that can enhance emotional balance and to develop job stress management program.

• Journal of dental hygiene science
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• v.10 no.5
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• pp.335-340
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• 2010

This study was performed to evaluate the fracture strength of the dental zirconia veneering ceramics for zirconia ceramic core. Six commercial zirconia veneering ceramics were used in this study, namely E-Max(Ivoclar vivadent, Inc, Liechtenstein), Creation ZI(KLEMA Dental produckte GmbH, Austria), Cercon ceram kiss(Degudent, GmbH, Hanau-Wolfgang, Germany), Triceram(Dentaurum, Ispringen, Germany), Zirkonzahn(Zirkonzahn GmbH, Italy), Zirmax(Alpadent, korea). All samples were prepared according to the relevant instructions of manufacture. Disc specimens were prepared to the final dimensions of 17 mm in diameter and 1.5 mm in thickness. The biaxial flexure strength test was conducted using a ball-on-three-ball method. All specimens were tested in a moisture-free environment. Average flexural strengths were analyzed with Weibull analysis and one-way analysis of variance(ANOVA). Significant differences were founded between the mean flexural strength values of five commercials zirconia veneering ceramics and the other. The flexural strengths and Weibull modulus were similar to those of five groups E-Max(EM), Creation ZI(CR), Cercon ceram kiss(CE), Triceram(TR), Zirkonzahn(ZI) with the exception of Zirmax(ZM). The biaxial flexural strength from Cercon ceram kiss(CE) was higher than those of other groups. Fracture analysis showed similar results for these five groups.

• Journal of Korean society of Dental Hygiene
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• v.13 no.5
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• pp.749-757
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• 2013

Objectives : The aim of the study is to investigate the relationship between salivary flow, palate recognition threshold, DMFT index and oral health influence point (OHIP-14) of the adults over 40 years old. Methods : Salivary flow and taste recognition threshold were measured in 220 adults over 40 years old from three dental clinics in Daegu from January 3 to February 4, 2012. A total of 208 questionnaires were analyzed. Results : The adults recognized the sour taste in low concentration level when the salivary flow was faster. DMFT index was low in those who recognized sweet and sour taste that affected OHIP-14. Conclusions : Tooth decaying food must be restricted because of its high acidity in the past despite the individuals' taste recognition threshold was neglected. Before the diet control, it is necessary to measure the taste threshold of the individuals. Training for improving salivary flow is very important to prevent dental caries and to preserve good taste.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.11
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• pp.52-56
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• 1996

The elevation of present medical service using advanced science contributes to offer medical examination and treatment of good quality under the subject of patient satisfaction as well as patient impression. The dental service field charging some part of public health promotion and public welfare promotion also intends to improve the dental examination and treatment quality utilizing advanced science. The object of this research is the development of dental patient education system (DPES) using multimedia of new technology. DPES can be employed for these object, harmonious operation of dental examination and treatment, treatment quality improvement, disease notice to patient under the subject of patient satisfaction and patient impression, explanation of some selective treatment course, the verification of treatment necessities and treatment validation, and the improvement of treatment effect through the oral cavity sanitation education in the sense of prevention. This research also serves the development environment, the step to collect educational document, visual information and to structure those, and the examination of DPES efficiency in clinic.

• Journal of Korean society of Dental Hygiene
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• v.22 no.6
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• pp.531-539
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• 2022

Objectives: This study aimed to design a CRA questionnaire specifically for Korean children and adolescents based on the results of two Delphi survey completed by dental professionals. Methods: Based on the CAMBRA^® CRA tool, updated in 2019, we constructed a questionnaire on the oral environment and behavior of children and adolescents. Then, the CVR and I-CVI were evaluated using the results of the first and second Delphi surveys involving 20 professionals. Results: After the first Delphi survey, six items were considered invalid because their CVR and I-CVI were below the recommended values of 0.42 and 0.78, respectively. After receiving feedback from the professional panels, nine items were removed. In the second Delphi survey, the questionnaire contained a total of 21 items, all of which showed good CVR and I-CVI. After modifications based on the opinions of professional panels, the questionnaire was finalized to have 21 questions. Conclusions: The finalized questionnaire with 21 items, based on the opinions of professional panels, showed excellent CVR and I-CVI for all the items. Structured programs with updated guidelines must be developed for Korean children and adolescents in further studies.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.26 no.2
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• pp.130-142
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• 2017

There are frequent cases of retreatment due to lack of communication between dentists and dental technicians during general prosthetic treatment. The success of large-scale therapy begins with small treatments. This report reminds you of the importance of communication through a simple example. To reproduce better colors and shapes, the dentist must provide specific and accurate information and feedback to the dental technician, and the dental technician must have the skills to accurately analyze and express it. In this process, we need to create an environment where we can exchange mutual opinion and produce better prostheses.

• Journal of The Korean Dental Society of Anesthesiology
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• v.14 no.4
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• pp.233-236
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• 2014

In order to reduce jaw fracture accompanied by basal skull or nasal fracture, submental intubation could be generally performed. Albeit submental intubation has been widely accepted, it could develop complications such as nerve injury, glandular duct injury, and orocutaneous fistula. Here, we suggest oral intubation for overcoming complications and providing more stable surgical environment in emergency case. Under oral intubation maintaining in retromolar triangle and buccal corridor space, intermaxillary fixation was successfully underwent in 38-years-old female patient with Le Fort I fracture accompanied by pneumocephalus.

• Journal of Drive and Control
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• v.20 no.1
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• pp.27-33
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• 2023

From the perspective of dental chair manufacturers, it is important to of localizing hydraulic system in order to secure market competitiveness. This study aims to develop the analysis model of a dental chair which overseas companies secure core technologies. The study follows the steps below. First, the component parts of the solenoid valve unit of a foreign leading company are analyzed and implemented in virtual environment. Second, dynamic behavior scenario is established based on solenoid valve signal chart provided by a foreign leading company. The analysis model is verified and its performance is analyzed using dynamic behavior according to each scenario. Third, a simulation is carried out to determine whether the cylinder velocity of designed hydraulic system surpasses 1cm/s as required by the design.