• The korean journal of orthodontics
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• v.40 no.3
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• pp.145-155
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• 2010

Objective: Lateral cephalometric radiographs have been the main form of resource for assessing two dimensional anteroposterior airway changes. The purpose of this study was to evaluate the three dimensional volumetric change in the upper airway space in Class III malocclusion patients who underwent mandibular setback surgery. Methods: Three dimensional cone-beam computed tomographs (CBCT) and their three dimensional reconstruction images were analyzed. The samples consisted of 20 adult patients (12 males and 8 females) who were diagnosed as skeletal Class III and underwent mandibular setback surgery. CBCTs were taken at 3 stages - Baseline (1.8 weeks before surgery), T1 (2.3 months after surgery), and T2 (1 year after surgery). Pharyngeal airway was separated according to the reference planes and reconstructed into the nasopharynx, the oropharynx and the hypopharynx. Measurements at Baseline, T1, and T2 were compared between groups. Results: The result showed the volume of the pharyngeal airway decreased significantly 2.3 months after surgery (p < 0.001) and the diminished airway did not recover after 1 year post-surgery. The oropharynx was the most decreased area. Conclusions: These findings suggest that mandibular setback surgery causes both short-term and long-term decrease in the upper airway space.

• The korean journal of orthodontics
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• v.38 no.4
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• pp.252-264
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• 2008

Objective: To aid the development of a frontal image simulating program, we evaluated the soft tissue frontal changes in relationship to movement of hard tissue with orthognathic surgery of facial asymmetry patients. Methods: Preoperative and postoperative frontal cephalograms and frontal view photographs of 45 mandibular surgery patients with facial asymmetry were obtained in a standardized manner. Vertical and horizontal changes of hard tissue and soft tissue were measured from cephalograms and photographs, respectively. Soft tissue change in result to hard tissue change was then analyzed. Results: Both vertical and horizontal correlation analysis showed a weak relationship between the changes. Hard tissue points that were picked for 1 : 1 mean ratio with soft tissue points did not show any significant relevance. For each soft tissue change, regressive equation was formulated by stepwise multiple regression analysis, and the equation for soft tissue Menton was most reliable in predicting changes. Both vertical and horizontal hard tissue changes were used together in prediction of vertical or horizontal soft tissue change. Conclusions: The results suggest that computerized image simulation using regression analysis may be of help for prediction of soft tissue change, while 1:1 mean ratio method is not useful.

• Journal of dental hygiene science
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• v.4 no.3
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• pp.111-115
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• 2004

This study was aimed to establish the self-concept as the dental profession and dedicate to the development of dental hygienist role by understanding the relation between the self-concept of dental hygienist and practice performance as dental hygienist. Following the thorough investigation of this correlation, the importance of self-concept as the dental profession was confirmed, and the understanding about the practice performance as dental hygienist was renewed. Dental hygienist working in dental clinic located in Jeonju city, Jeollabuk-Do were selected as the subjects of this study, and the materials were collected from Mar. 11 to Mar. 25, 2002 for 15 days. SPSS was used for analysis of data to deal with ANOVA and verification of Pearson correlation. The results of this research can be summarized as follows; 1. In comparison of the degree of professional self-concept according to the general characteristics of the subjects, there were significant differences in religion(p<.05) and educational background(p<.01). 2. In comparison of the degree of practice performance according to the general characteristics of the subjects, the results showed the significant difference in religion(p<.05). 3. There were highly significant correlation between the professional self-concept and practice performance as dental hygienist(F=.663, p<.001).

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.2
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• pp.160-167
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• 2021

The purpose of this study was to investigate the prevalence and characteristics of pre-eruptive intracoronal radiolucencies (PEIR) from panoramic radiographs in Korean children and adolescents. This study examined panoramic radiographs of 3,000 patients aged between 5 and 14 years old who visited ten dental hospitals in Korea. The age and gender of the patients, the tooth type, the number of intracoronal radiolucent lesions, and the location and size of the lesions were recorded. The overall prevalence of patients with PEIR was 2.5%. The difference in the presence of PEIR between both genders was not significant. Within each tooth type, the mandibular first molar showed highest prevalence of PEIR (29.6%). The central part of the crown was the most frequently observed location of PEIR (56.8%). The size of the PEIR lesions was mostly limited to less than one-third of the thickness of coronal dentin.

• Journal of Korean society of Dental Hygiene
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• v.19 no.5
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• pp.651-664
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• 2019

Objectives: This study surveyed the application of Comprehensive Dental Hygiene Care (CDHC), based on non-surgical periodontal therapy within the educational curricula of Korean universities and examined whether they recognized the need for CDHC. Methods: This study analyzed data from professors of dental hygiene practicum related subjects in 75 Korean universities. The collected data were analyzed using a Chi-square test, a Mann-Whitney U-test, and a Kruskal Wallis test via SPSS (Ver. 21.0). Results: First, the application scope of CDHC was higher in four-year universities than three-year ones with the scope of several characteristics increasing along with enrollment quota. The application scope of dental hygiene plans and actions increased with the number of patient practices in terms of periodontal evaluations. Second, the needs of the dental hygiene courses were more than 4 points in all characteristics. Although four-year universities exhibited higher points than three-year ones, there was no significant difference found except other test. Finally, all universities based their dental hygiene courses on case histories, oral and maxillofacial information, hard tissue modules, periodontal issues, and other tests, with needs also being high. Meanwhile, the application scope of the dental hygiene course evaluations was lowest in all characteristics. Conclusions: There were no significant differences in dental hygiene curricula among the universities. However, highly qualified and standardized educational courses and lectures should be developed by the Korean evaluation center for dental hygiene curricula using various studies as the basis of theory and practical classes, the total number of terms, number of case studies used, number of students per class, ratio of students to professor, and so on.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.4
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• pp.330-337
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• 2018

In edentulous patients, implant - supported fixed prosthesis treatment has been proved to be useful, but involves complex treatment process. On the other hand, in the modern dentistry, digital technology has been developed day by day and it has expanded its range to the implant restoration of edentulous patients. In this case, a digital system was used for all stages of diagnosis, surgery, design and fabrication of provisional implants fixed prosthesis restoration in 66-year-old mandibular edentulous patients. In the preoperative diagnosis stage, a provisional restoration was designed based on the mucosal scan using the intraoral scanner and the stable occlusion of prefabricated complete denture of the patient. After flapless implant surgery using the surgical guide, the prefabricated interim restoration was connected to the implant and used as immediate provisional restoration. The final restoration was designed and fabricated by transferring the vertical dimension and the centric relation of the provisional restoration with stable occlusion using digital technology. We report a simple protocol of implant treatment in edentulous patients by using digital techniques to preserve the patient's vertical dimension and occlusion.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.4
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• pp.269-277
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• 2017

Purpose: The aim of this study is to compare the performance of two piezoelectric engine systems by surveying satisfaction from dental clinicians. Materials and Methods: Two piezoelectric systems were evaluated: TRAUS XUS10 (Saeshin), PIEZOSURGERY touch (Mectron). For this study, 20 dentists responded to the 11 questionnaires in which 5 point Likert-type scale was used. The two devices were operated for 10 seconds and measured 5 times to compare the maximum noise values. In heat emission test, the handpiece was operated for 3 minutes and heat was measured at three positions each. Results: TRAUS XUS10 had higher satisfaction level on motor noise (P < 0.05). About function key and handpiece heat generation, PIEZOSURGERY touch showed higher satisfaction (P < 0.05) than TRAUS XUS10. The maximum noise level for each of the devices was confirmed to be 56.6 dB for the TRAUS XUS10 and 56.0 dB for PIEZOSURGERY touch. The two piezoelectric engines satisfied the safety standards with an operation temperature below $41^{\circ}C$ after having been operated for 3 minutes. Conclusion: Except for the function key and handpiece heat emission, TRAUS XUS10 has comparable performance with PIEZOSURGERY touch.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.1
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• pp.92-101
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• 2003

Under this thesis, 235 patients with dental problems treated under general anesthesia at the Pediatric Dentistry Clinic of Yonsei Dental College were surveyed and their age distribution, reasons for taking general anesthesia, duration of anesthesia, duration of dental procedure, dental treatment peformed and complications were analyzed. A questionnaire survey was also conducted to analyze degrees of anxiety and satisfaction among their parents according to the parents' age, educational background and experience of general anesthesia, as well as the patients' age and past dental history. Following are the results. 1. When the patients were treated under general anesthesia, the degree of anxiety of their mothers was higher than that of their fathers. It appeared that the higher the parents' educational background was, the less their anxiety. 2. The higher the parents' educational level was, the higher the degree of satisfaction after treatment under general anesthesia. 95 cases (87.2%) responded that they would accept such treatment again, if needed. From the result, dental treatment under general anesthesia causes anxiety for parent but the parent's satisfaction level was high. And that was the way gives good quality of dental service to unmanagable patients.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.4
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• pp.265-277
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• 2014

Purpose: The purpose of this study was to investigate the differences of displacement pattern depending on type of sliding jig and application method during maxillary molar distalization with temporary anchorage devices (TADs). Materials and Methods: Maxilla with normal tooth size and arch shape was selected to create a 3-dimensional finite element model, which included the bracket, orthodontic main archwire, removable sliding jig (R-jig). The orthodontic mini-implant anchorage was set 8 mm superiorly from main archwire, buccally between the second premolar and first molar. The base experimental design was Condition 1, which was composed $0.019{\times}0.025$ inch stainless steel (SS) of wire size of R-jig, 200 gm force, un-tied state. And the other designs varied to wire size of R-jig, magnitude of force. The results are as follows. Results: As the wire size of R-jig was increased, the deformation of R-jig was decreased. However, the displacement of second molar wasn't different each other. As the force to second molar was increased, the more displacement of second molar was observed, and the more distal tipping movement, vetical displacement was observed. Conclusion: R-jig can get distal teeth movement in orthodontic treatment without side effects.

• Korean Journal of Microbiology
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• v.49 no.4
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• pp.301-308
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• 2013

Programmed Death-1 (PD-1) is one of the important immune-inhibitory molecules which was expressed in T cells, B cells, NKT cells, and macrophages activated by various immune activating factors. Lipopolysaccharide (LPS), the major component of the outer membrane of Gram-negative bacteria, is one of the crucial immunogens for PD-1 expression. However, there are only a few reports on the expression mechanisms of PD-1 in innate immune cells. In this study, we investigate the expression mechanisms of PD-1 in LPS-stimulated Raw264.7 cell lines by RT-PCR, Western Blot, flow cytometry as well as ChIP assay and co-immunoprecipitation. When Raw264.7 cells were stimulated with LPS, PD-1 expression was greatly up-regulated via PI3K and p38 signaling. Primary macrophages isolated from LPS-injected mice were also shown the increased expression of PD-1. In promoter assay, NF-${\kappa}B$ and IRF-1 binding regions in mouse PD-1 promoter are important for PD-1 expression. We also found that the co-activation of NF-${\kappa}B$ and IRF-1 is indispensable for the maximum PD-1 expression. These results indicate that the modulation of PD-1 expressed in innate immune cells could be a crucial for the disease therapy such as LPS-induced mouse sepsis model.