• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.3
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• pp.530-534
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• 2001

Many dental practitioners are bonding amalgam to tooth structure. The potential advantage of this procedure, suggested by in vitro test results, are reduced microleakage, which could lead to a reduced incidence of postoperative sensitivity ; increased strength of the prepared tooth ; and retention of restoration in less retentive preparations, with the potential fer conserving tooth structure. Although in vitro studies support this procedure, its efficacy has not been adequately confirmed in the clinical environment. The authors placed traditional Class I and Class II, bonded and unbonded amalgam restorations in 76 teeth. Fuji I Glass Ionomer luting cement was the bonding agent selected. Marginal adaptation were evaluated after two years. the authors found no significant difference in marginal adaptation between bonded and unbonded restorations.

• Journal of Korean society of Dental Hygiene
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• v.18 no.5
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• pp.853-862
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• 2018

Objectives: This study involved a non-equivalent control group, pre-test/post-test measurement experiment to evaluate the efficacy of distributing plaque disclosing agents to healthy adults living in South Korea and promoting its self-application. Methods: O'Leary index, PHP index, oral health behavior intention, and oral care satisfaction were used as research tools. A notice was posted on the bulletin board from September 12 to October 15, 2016, to recruit adults aged 20-50 years. Data were analyzed using SPSS Version 22.0, and frequency analysis, Pearson's chi-squared, one-way analysis of variance (ANOVA), Kruskal-Wallis, and repeated measures ANOVA were performed. Results: The O'Leary index was significantly reduced in the group (p<0.01), and time (p<0.01) after education and width of the decrease had the highest score in the group that received education on plaque disclosing only. They were followed by the group that received education on plaque disclosing and the rolling method, the group that received education on the rolling method alone, and the control group. The PHP index significantly decreased in the group(p<0.01) and time (p<0.01), and the group time (p=0.039) after education, and width of the decrease had the highest score in the group that received education on plaque disclosing and rolling method. They were followed by the group that received education on plaque disclosing alone, the group that received education on the rolling method alone, and the control group. Conclusions: Based on the aforementioned findings, the direct use of plaque disclosing had a marked effect on self-oral care. These results suggest that the self-application of plaque disclosing could be an effective self-care method for improving the oral environment.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.72-72
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• 2018

A dynamic fatigue characteristic of dental implant system has been evaluated with applying single axial compressive shear loading based on the ISO 14801 standard. For the advanced dynamic fatigue test, multi-directional force and motion needed to be accompanied for more information of mechanical properties as based on mastication in oral environment. In this study, we have prepared loading and motion protocol for the multi-directional fatigue test of dental implant system with single (Apical/Occlusal; AO), and additional mastication motion (Lingual/Facial; LF, Mesial/Distal; MD). As following the prepared protocol (with modification of ISO 14801), fatigue test was conducted to verify the worst case results for the development of highly stabilized dental implant system. Mechanical testing was performed using an universal testing machine (MTS Bionix 858, MN, USA) for static compression and single directional loading fatigue, while the multi-directional loading was performed with joint simulator (ADL-Force 5, MA, USA) under load control. Basically, all mechanical test was performed according to the ISO 14801:2016 standard. Static compression test was performed to identify the maximum fracture force with loading speed of 1.0 mm/min. A dynamic fatigue test was performed with 40 % value of maximum fracture force and 5 Hz loading frequency. A single directional fatigue test was performed with only apical/occlusal (AO) force application, while multi directional fatigue tests were applied $2^{\circ}$ of facial/lingual (FL) or mesial/distal (MD) movement. Fatigue failure cycles were entirely different between applying single-directional loading and multi-directional loading. As a comparison of these loading factor, the failure cycle was around 5 times lower than single-directional loading while applied multi-directional loading. Also, the displacement change with accumulated multi-directional fatigue cycles was higher than that of single directional cycles.

• Journal of the korean academy of Pediatric Dentistry
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• v.1 no.1
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• pp.57-61
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• 1974

The Study reported here was designed to analyze the prevalence of Dental Caries in the primary teeth of monozygote twins, and to ascertain and compare the intrapair differences with the intrapair differences in control pairs. The prevalence of dental caries in the primary teeth of 40 pairs of presumably monozygote twins, based on phenotypic analysis, was studied. The age range was from 3 to12 years. The control group consisted of pairs that included a twin chosen at random and an unrelated child of the same sex and age, so that for each pair of twins there was a corresponding control pair. The clinical examination was carried out by an operator using an oral mirror and sharp explorers, and with good lighting. 40 pairs of twins were examined with a total of 4,950 primary tooth surfaces (990 primary teeth) and 40 control pairs with a total of 4,935 primary tooth surfaces (987 primary teeth). Five surfaces were considered for each tooth. After the def individual index was determined, the ratio between this index and the number of examined surfaces was established in each case, the cer (Caries experience rate) index. The def and cer averages were determined for the subjects and the controls. All intrapair differences in twin and control groups were compared following the paired sampling method. The following conclusions were made: 1. Intrapair differences in the control group were significantly greater than in twins, when defs, ds, es, fs, and cer were compared. 2. The genotype appeared to be a determining factor in dental caries susceptibility or resistance, although the environment played an important role as well. 3. Intrapair differences in American children were significantly greater than in Korean when defs, es, fs, and cer were compared, but ds was equal.

• Korea Journal of Hospital Management
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• v.22 no.4
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• pp.1-15
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• 2017

This study was designed to analyze the effect of servicescape and human service quality on patients' internal response and their behavioral intention in dental care organizations. Self-administered survey questionnaires with structured instruments were developed, and a total of 226 responses were used for statistical analyses using SPSS Windows version 18.0 program and AMOS 18.0 program. Major findings of the study are as follows. First, among other servicescape components, air condition environment was found to have a positive effect on patients' cognitive and physiological responses, while signals and symbols had a positive effect on cognitive and emotional responses. Second, the competence, among other factors of the human service quality, had positive influence on cognitive and emotional responses, while customer understanding affected positively on emotional response. Third, none of the servicescape components showed a direct effect on patients' behavioral intention, but their influence was mediated by internal responses. However, customer understanding, among other human service quality factors, had a direct effect on patients' behavioral intention. Fourth, emotional response, among other internal response factors, proved to have positive influence on behavioral intention. Results from this study suggest that dental care service providers can increase their competitiveness and customer satisfaction by understanding and improving the most important areas of servicescape and human service quality.

• Anatomy and Cell Biology
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• v.51 no.4
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• pp.236-242
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• 2018

The dog frontal sinus may represent an alternative model dental implant research; its topographical resemblance to the maxillary sinus renders it a potentially favorable experimental environment. The aim of this study was thus to elucidate the anatomical configuration of the canine frontal sinus and histological characteristics, and to determine whether it could be a new canine experimental model for dental implant research. Twenty-four sides of canine frontal bones were harvested. The distance from the nasion to the emerging point of the lateral aspect of the canine frontal sinus was measured with the aid of Lucion software. The thicknesses of the canine frontal sinus wall were measured, and the two specimens stained with hematoxylin and eosin. The mean distance from the nasion to the emerging point of the lateral aspect of the canine frontal sinus was 16.0 mm. The mean thicknesses of the canine frontal bone at 3, 6, 9, 12, and 15 mm lateral to the midsagittal plane were 2.3, 2.7, 3.2, 3.8, and 3.7 mm, respectively. The canine frontal sinus was lined with pseudostratified ciliated columnar epithelium. These data suggest that the canine frontal sinus is a suitable alternative to the canine maxillary sinus as a model for studying various sinus augmentation protocols.

• Journal of dental hygiene science
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• v.21 no.1
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• pp.45-51
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• 2021

Background: Periodontal disease, also known as gum disease, is a major dental inflammatory disease with a very high prevalence; it is the main cause of tooth loss. Therefore, diagnostic biomarkers that can monitor gum inflammation are important for oral healthcare. Since the gingival crevicular fluid (GCF) adequately reflects changes in the periodontal environment, they have become a target for the development of effective diagnostic biomarkers for periodontitis. In the present study, the level of the target molecules suggested as diagnostic biomarkers for periodontitis were analyzed in GCF samples collected from healthy individuals and periodontitis patients. In addition, useful targets for the diagnosis of periodontitis were evaluated. Methods: GCF samples were collected from healthy individuals and periodontitis patients using absorbent paper points. SDS-PAGE and Coomassie staining were performed for protein analysis. The protein concentrations of GCF specimens were determined using the Bradford method. The levels of the target molecules appropriate for diagnosing periodontal disease were measured by ELISA, according to the manufacturer's protocol. Results: The protein concentration of GCF collected from periodontitis patients was 3.72 fold higher than that in an equal volume of GCF collected from healthy individuals. ELISA analysis showed that the level of interukin-6 (IL-6), IL-8, metalloproteinases 2 (MMP-2), MMP-9, tumor necrosis factor-alpha (TNF-α), azurocidin, and odontogenic ameloblast-associated protein (ODAM) were higher in the GCF samples from the periodontitis patients than in those from the healthy individuals. However, the level of IL-6 and TNF-α were relatively low (> 5 pg/ml). The prostaglandin E2 (PGE2) levels were not significantly different between the two GCF samples. Conclusion: These results indicate that IL-8, MMP-2, MMP-9, azurocidin, and ODAM are potentially useful diagnostic biomarkers for periodontitis; combining multiple biomarkers will improve the diagnostic accuracy of periodontitis.

• Journal of dental hygiene science
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• v.22 no.1
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• pp.30-36
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• 2022

Background: Nowadays, dental health problems in Indonesia are still quite high. It is one of which influenced by low public awareness of the importance of maintaining the health of teeth and mouth that can be measured by toothbrushing behavior. Based on the results of RISKESDAS 2018, only 2.8 percent of the population has a proper toothbrushing behavior. Behavior tends to form at age 6 to 12 years. At this age, children begin to develop habits that tend to settle until adulthood, including toothbrushing behavior. Social cognitive theory is a theory of behavioral change that explains that behavioral changes are influenced by the environment, personal, behavior where these three factors influence each other. This study aims to identify changes in the dental behavior of second grades students before and after the joint toothbrushing at school for 21 days. Methods: A pre-experimental study-design was conducted on elementary school by pre-post treatment method where there are 2 classes that get intervention and 2 other classes as control. A joint toothbrush is performed every morning before the school activities begin. Before and after the joint toothbrushing, all classes are given questionnaires to see if there are any changes in behavior seen through knowledge, attitudes, and practice. Results: Respondent group showed increasement on their knowledge, attitudes, and behaviors towards toothbrushing. In contrast, the control groups showed no significant differences in the 3 factors. Conclusion: In this study the education of toothbrushing through environmental changes is quite effective in elementary school children. Insights into the benefits of this program and refinements of optimally targeted intervention, including longitudinal studies are needed to improve the results.

• Journal of Animal Reproduction and Biotechnology
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• v.39 no.2
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• pp.95-104
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• 2024

Background: In healthy dentin conditions, odontoblasts have an important role such as protection from invasion of pathogens. In mammalian teeth, progenitors such as mesenchymal stem cells (MSCs) can migrate and differentiate into odontoblast-like cells, leading to the formation of reparative dentin. For differentiation using stem cells, it is crucial to provide conditions similar to the complex and intricate in vivo environment. The purpose of this study was to evaluate the potential of differentiation into odonto/osteoblasts, and compare co-culture with/without epithelial cells. Methods: MSCs and epithelial cells were successfully isolated from dental tissues. We investigated the influences of epithelial cells on the differentiation process of dental pulp stem cells into odonto/osteoblasts using co-culture systems. The differentiation potential with/without epithelial cells was analyzed for the expression of specific markers and calcium contents. Results: Differentiated odonto/osteoblast derived from dental pulp tissue-derived mesenchymal stem cells with/without epithelial cells were evaluated by qRT-PCR, immunostaining, calcium content, and ALP staining. The expression of odonto/osteoblast-specific markers, calcium content, and ALP staining intensity were significantly increased in differentiated cells. Moreover, the odonto/osteogenic differentiation capacity with epithelial cells co-culture was significantly higher than without epithelial cells co-culture. Conclusions: These results suggest that odonto/osteogenic differentiation co-cultured with epithelial cells has a more efficient application.

• Journal of dental hygiene science
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• v.16 no.2
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• pp.142-149
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• 2016

The number of male dental hygienists has been continuously increasing in dental services. The purpose of this study aimed to identify the relationship between job stress, job satisfaction, and turnover intention in male dental hygienists and to provide basic data to improve their job satisfaction. The study population was 110 Korean male dental hygienists working for dental clinics or hospitals. The data were collected from November 10 to December 7, 2015. After an explanation about the objective of the study, 110 questionnaires were distributed via email, and 97 responses were analyzed using SPSS. Overall averages of job stress, job satisfaction and turnover intention in male dental hygienists were 3.05, 2.92, and 3.47 out of 5, respectively. Some sub-factors of job stress, including interpersonal relationships at the workplace and future prospects of dental clinics, were proven to have statistically significant negative influence on job satisfaction (p<0.001). Regression analysis was performed with job stress and job satisfaction as independent variables and turnover intention as a dependent variable. Results showed that job stress had a positive effect on turnover intention (p<0.01) while job satisfaction had a negative effect on turnover intention (p<0.001). Job satisfaction was revealed to have statistically significant negative influence on turnover intention (p<0.001). Some of sub-factors of job stress, including work environment and future prospects of dental clinics and professional position, had a positive effect on turnover intention (p<0.05). The study showed that higher job stress led to higher turnover intention, and higher job satisfaction led to lower turnover intention. Accordingly, job stress and job satisfaction are critical factors for turnover intention in male dental hygienists.