• Journal of Technologic Dentistry
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• v.42 no.3
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• pp.228-233
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• 2020

Purpose: This study aimed to assess and compare the marginal fit of ceramic-based hybrid resin restoration (HYB) and zirconia restoration (ZIR) for dental computer-aided design/computer-aided manufacturing systems. Methods: A stainless steel master model was produced. The impression was first made with silicone, and then stone working models were produced. A total of twenty restorations were fabricated with two different materials: ZIR and HYB. The silicone film thickness of the marginal gap was measured using a digital microscope; digital photos were taken at a magnification of ×160, and then analyzed using a measurement software. The values of the result were evaluated with the independent-sample t-test (α=0.05). All statistical analyses were performed with a statistical software. Results: The mean values for the marginal gap was 37.14±2.96 ㎛ for HYB, compared with 40.37±5.26 ㎛ for ZIR. No significant difference was found between ZIR and HYB (p=0.107). Conclusion: As a result, the marginal fit of the restoration fabricated using the hybrid resin was better than that of the restoration fabricated using zirconia. Also, the marginal fit of all groups was below the clinical acceptable range of 120 ㎛. Thus, HYB for dental CAD/CAM system in this study is expected to be suitable for clinical use in dentistry.

• Journal of Technologic Dentistry
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• v.16 no.1
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• pp.43-56
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• 1994

The object of this study is, after the dental technology department is developed into the three-year curriculum and so new curriculum is needed, to compare, analyze, and appreciate the two-year model curriculum that has been practiced in our country, to analyze the curriculum and national quality system practiced in the developed country like U. S. canada, Germany and Japan, and, on the basis of the result from the upper part and inquiry result in the dental technology faculty commity of the nationwide junior college, to establish the new curriculum that is suitable the condition of our dental technology department in the junior college. 1) Since the width of the education is broader after the dental technology department is developed into three-year curriculum from the two-year curriculum, the course of study connected with the dental technology is added. 2) The fundamental course is propounded and the practical course which is needed on the spot is assigned. 3) Since the importance of the practical education is understood time and unit of the experimental practice is extended. 4) The time control in the curriculum commected with the national examination is adjected. 5) On the basis of the actual experience, the actual course is propound and time and unit are added widely to uplift the adjustment of the current environment of the dental technology.

• The Korean Journal of Health Service Management
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• v.6 no.4
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• pp.1-12
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• 2012

The objective of this study was to identify the current status of use and respective work scopes of dental hygienists and nursing assistants as perceived by dentists, thereby obtaining a model for how to efficiently use oral health assistance personnel. This study was based on a self-reported survey administered to a total of 126 dentists. The following findings were observed. Where competition among neighborhood clinics was relatively high, nursing assistants tended to be used as a resource to assist dental hygienists, whereas where it was relatively low, they were more likely to be considered to work as full substitutes for regular dental hygienists. Looking at the scopes of practice, dental hygienists were allowed to deal with matters of preventive care, oral health education, and health insurance claims. On the other hand, nursing assistants were allowed to be in charge of taking X-ray pictures from the outside and inside of mouth and keeping medical devices clean and safe. This study is expected to contribute to establishing more reasonable oral heath personnel structure design decisions.

• 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.24 no.4
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• pp.321-331
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• 2024

Objectives: This study aimed to investigate the digital literacy and major satisfaction levels of dental hygiene students and identify the interrelationships between them as well as the factors related to major satisfaction. Methods: An online survey was using a structured questionnaire was conducted with 223 dental hygiene students. Digital literacy and major satisfaction were measured using a 5-point Likert scale, and correlation and multiple regression analyses were performed. Results: The participants' digital literacy averaged 3.87 points, and their major satisfaction averaged 3.82 points. The digital literacy factor related to major satisfaction was critical thinking skills (β=0.747, p<0.001). This indicates that the higher the critical thinking skills, the higher the major satisfaction. The explanatory power of the model was 63.7%. Conclusions: Critical thinking skills as a factor of digital literacy were found to influence dental hygiene students' major satisfaction, suggesting that a curriculum that can increase critical thinking can improve major satisfaction.

• Journal of dental hygiene science
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• v.15 no.4
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• pp.430-436
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• 2015

This study examined the correlation of educational experience with practical behavior in infection control. Subjects were 152 dental hygienists in Gwangju from September 15 to October 5, 2015. The ratio of dental hygienists educated on infection control was higher in those worked in dental care with 2~4 dentist for 2~5 years and lower in those worked in dental cared with 1 dentist for 2~5 years (p<0.05, p<0.001). The dental hygienists with or without educational experience in infection control exhibited the highest activity rate in hand wash and the lowest in face protection. Barrier in health belief, was lower with the need for education in infection control among the factors affecting on the activity in infection control. The activity was higher with susceptibility and cue to action (p<0.05). Based on the results, education program on infection control should be developed, and applied periodically and obligatorily for dentist and all staffs of dental care to remove susceptibility and barrier, and to enhance cue to action. This will result the effective control of infection by elevating the health belief.

• The Journal of Advanced Prosthodontics
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• v.9 no.4
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• pp.244-251
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• 2017

PURPOSE. The purpose of this study was to determine fracture resistance and failure modes of three-unit fixed dental prostheses (FDPs) made of lithium disilicate pressed on zirconia (LZ), monolithic lithium disilicate (ML), and monolithic zirconia (MZ). MATERIALS AND METHODS. Co-Cr alloy three-unit metal FDPs model with maxillary first premolar and first molar abutments was fabricated. Three different FDPs groups, LZ, ML, and MZ, were prepared (n = 5 per group). The three-unit FDPs designs were identical for all specimens and cemented with resin cement on the prepared metal model. The region of pontic in FDPs was given 50,000 times of cyclic preloading at 2 Hz via dental chewing simulator and received a static load until fracture with universal testing machine fixed at $10^{\circ}$. The fracture resistance and mode of failure were recorded. Statistical analyses were performed using the Kruskal-Wallis test and Mann-Whitney U test with Bonferroni's correction (${\alpha}=0.05/3=0.017$). RESULTS. A significant difference in fracture resistance was found between LZ ($4943.87{\pm}1243.70N$) and ML ($2872.61{\pm}658.78N$) groups, as well as between ML and MZ ($4948.02{\pm}974.51N$) groups (P<.05), but no significant difference was found between LZ and MZ groups (P>.05). With regard to fracture pattern, there were three cases of veneer chipping and two interfacial fractures in LZ group, and complete fracture was observed in all the specimens of ML and MZ groups. CONCLUSION. Compared to monolithic lithium disilicate FDPs, monolithic zirconia FDPs and lithium disilicate glass ceramics pressed on zirconia-based FDPs showed superior fracture resistance while they manifested comparable fracture resistances.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.227-235
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• 2021

The purpose of this study was to investigate the association factors of dental infection control by applying the health belief model in the dental hygienists. This study subject was 142 dental hygienists from 15 to July 5, 2020. Data were analyzed by chi-square test ANOVA, correlation analysis, and multiple regression analysis using SPSS version 23.0. The performance of dental infection control in accordance with the general characteristics of research subjects was high in case when they had educational experiences of infection control, and when they 'always' did medical examinations by interview about infectious diseases(p<0.01). The group of dental hygienists working for dental clinics with less than average 50 patients a day showed the highest rate of wearing a mask and latex gloves as personal protective gears(p<0.05),(p<0.01). When the wearing of protective goggles(face shield) and the frequency of exchanging masks after the outbreak of COVID-19 were more, the performance for infection control was increasing(p<0.05),(p<0.01),(p<0.001). In this study, it is difficult to generalize the results of the study because the research area and the subject are limited by selecting the subjects by convenience extraction, and focusing on the degree of awareness of infection control by dental hygienists, the actual status of infection control in dentistry is carefully illuminated. What you didn't do can be seen as a limitation. Considering the results of this study, the performance of infection control could be increased by removing obstacles and increasing the importance and perceived benefits of infection control of dental hygienists.

• The Journal of the Korean dental association
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• v.52 no.1
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• pp.17-26
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• 2014

Computerized 3D virtual dental models are currently available, and their use has started to improve treatment outcomes. The accuracy of digital models has been demonstrated by many studies and various intra-oral scanners are innovated for short scanning time and high precision. Recently, a digital model was combined with a high technology computer-driven system, which was developed for the application of a digital set-up and indirect bonding of lingual attachments. In this section, virtual treatment planning using a virtual set-up program is be introduced, and the clinical applications and accuracy of computer-generated indirect bonding are discussed.

• Journal of Technologic Dentistry
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• v.40 no.3
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• pp.183-190
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• 2018

Purpose: The purpose of this study was to evaluated the process of model analysis, design, and production for a full mouth prosthetic rehabilitation of function, esthetics, and pronunciation. Methods: This is a case report of class III malocclusion with a severe anterior incisor occlusion and a prosthetic treatment of patient with poor occlusion of posterior teeth. A provisional restoration based on the diagnostic wax-up was applied to the patient. And then functions, esthetics, and occlusal stability were observed during 4 week tracking period. Final restorations were delivered and evaluated based on a systematic analysis, diagnosis and treatment plan. Results: We confirms that this case study obtained the satisfactory results in terms of functions and esthetics. Conclusion : If we can give the patient the continuous evaluation and progress monitoring, we expect the dentist and the dental technician to design the prosthesis successfully.