• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.196-196
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• 2016

치과나 기공소로부터 높은 원가로 인한 재료선택에 어려움을 겪고 있어 귀금속 금합금의 물성을 가질 수 있도록 하면서 가격급등으로 인한 문제 해결하기 위한 비귀금속 합금으로 대체가 필요하기에 이에 따른 연구가 이루어져 국산 제품의 상품화를 위해 파라듐을 이용하여 적합한 새로운 합금을 개발하는 것이 필요하다. 치과용 골드합금은 미국치과의사 협회의 구정에 의하면 1형부터 4형까지 분류하고 있으며 3형에 해당하는 강도와 기계적인 특성을 갖도록 파라듐으로 대체하는 연구가 진행중이거나 시판되고 있다. 따라서 본 연구에서는 2형, 3형 및 4형을 대체가능하도록 팔라듐을 기반으로 한 새로운 합금을 설계하고 합금의 성분원 소인 Au(1~5), Pd(20~25), Ag(70~75), In(1.5) 및 Zn(2)등으로 조성을 변화시켜 측량 후 합금을 제조하기 위하여 아르곤 분위기하의 진공아크용해로를 이용하여 용해하였다. 정량된 금속을 진공아크 용해로에 장입하고 용해는 균질한 합금이 되도록 최소한 6회 이상 용융을 실시하며 합금성분의 손실이 발행하지 않도록 보정을 하였다. 합금의 미세조직 관찰을 위하여 샘플을 고속 다이아몬드 정밀 절단기(Acculom-5, STRUERS, Denmark)를 이용하여 절단한 후 2000 grit의 Sic 연마지에서 단계적으로 $0.3{\mu}m$ 알루미나 분말까지 연마한 후 초음파 세척을 하였다. 준비한 시편은 KCN과 $(NH_4)_2S_2O_8$을 1:1로 혼합한 부식액으로 에칭한 후 OM과 SEM을 이용하여 조직을 관찰하였으며 각 샘플의 성분변화는 EDS 분석을 통해 확인하고 결정구조는 XRD를 사용하여 분석하였다. 경도시험은 비커스경도시험기를 이용하여 5kg의 하중을 30초간 작동시켜 압흔을 연결된 micron으로 평균값을 측정하였다. 각 시편의 부식거동은 POTENTIOSTAT(Model PARSTAT 2273, EG&G, USA)을 이용하여 구강 내환경화 유사한 $36.5{\pm}1^{\circ}C$의 0.9% NaCl에서 실시하였다. 인가전위는 -1500mV에서 1000mV까지 1.67 mV/min의 주사속도로 인가하여 시험을 수행하였으며 분극곡선으로부터 부식전위와 부식전류밀도 및 부동태영역의 전류밀도로 금속의 용출거동을 조사하였으며 부식이 끝난 시편은 FE-SEM과 EDS를 사용하여 조사하였다. 기계적인 특성은 Pd-Ag에 3wt%의 Au를 첨가한 합금이 Pd-Ag에 1.5wt%합금을 첨가한 경우에 비하여 기계적인 특성이 증가하고 내식성이 크게 증가하였다. 이들 합금에 Cu를 11wt%를 첨가한 경우는 비커스경도가 200이상으로 높게 나타났지만 내식성이 크게 감소하였다.

• Journal of Oral Medicine and Pain
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• v.37 no.2
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• pp.93-105
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• 2012

Let me introduce a teaching method to improve practice capacity in dental laboratary work. I applied theories of layers of modeling and reflection constituting cognitive apprenticeship and peer tutoring to my class. At internet uploading a file showing a practice procedure a week before the class of a course, I let students preview it. During the class I demonstrated the practice procedure in front of students. A superior student and an inferior student paired according to the previous practice grade and a feedback between a peer tutor and a peer tutee was activated. Late in the class, a student self-evaluated his own practice result and had a check of a professor. Finally he compared his own practice result with that in the file uploaded at internet and reflected. This teaching method led to improvement in students' satisfaction and efficiency of learning.

• Sleep Medicine and Psychophysiology
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• v.12 no.1
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• pp.64-67
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• 2005

Obstructive sleep apnea syndrome(OSAS) is a common disease in the field of otorhinolaryngology and is characterized by repeated upper airway occlusions occurring during sleep. OSAS can occur due to various etiologies of the nasal, oral, pharyngeal and laryngeal airway in adults. Nasal obstruction can be caused by septal deviation, nasal polyps, concha bullosa, choanal atresia, neoplasms, foreign body, postoperative/post-traumatic synechiae, various rhinitis and so on. There are various kinds of surgical treatment of OSAS including nasal surgery, LAUP, UPPP, surgery of tongue base, tracheostomy and so on, but the effect of nasal surgery on snoring and OSAS is controversial. The authors report the case of a patient who had experienced nasal obstruction, moderate snoring and OSAS and who improved after septoplasty and turbinoplasty.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.5
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• pp.401-407
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• 2009

Purpose : This study was designed to evaluate the clinical aspect of cysts which arised in the oral and maxillofacial region. Patients and Methods : We reviewed clinical record, radiograph, histopathologic and operative report of 155 patients who had been diagnosed as cysts and treated at the department of oral and maxillofacial surgery in Chonnam National University Hospital from January 2003 to December 2008. Gender, age, classifiaction, anatomic distribution, clinical sign and symptoms, treatment, complications and recurrence rate were studied. Results : 1. Among 155 patients, the male patients(64.5%) were more than the female(35.5%). 2. The average age ofthe patients was 37.2 years(ranging from 5 to 79 years). 3. In pathologic classification, radicular cyst and dentigerous cyst were most common cysts, irrespective of 73 cases(48.3%) and 35 cases(23.2%). 4. The frequently involved cystic regions were followed as mandibular molars(38.1%), and maxillary incisors(30.2%). 5. The frequent sequence of clinical symptoms was edema(29.9%), no symptom(18.9%), tenderness(13.9%), pain(11.5%) and abscess(9.4%). 6. The most prevalent treatment was the combination operation, such as cyst enucleation with extraction or endodontic treatment of the causative tooth(76.8%) 7. Among 155 cases, 2 cases that were treated using enucleation method were recurred(1.3%).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.1
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• pp.5-13
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• 2003

The purpose of this study is to determine the value of serum concentration of C-reactive protein(CRP) in comparison with ESR and leukocyte as the tools for diagnosis and follow-up study of infection. For this study, thirty-one patients with head and neck infection and thirty-two patients performed the orthognathic surgery were selected for experimental and control groups each other. we analyzed the blood sample daily to measure CRP, ESR and leukocytosis. The results of this study are as the following : 1. Serum C-Reactive Protein levels in the experimental group were higher than control group and the pattern of CRP changes continued to decline in both groups(P<0.001). 2. ESR changes in both groups were scattered without any special pattern. 3. Correlation between CRP and Leukocyte was higher than others(r=0.664, P<0.01). 4. In the Receiver Operating Characteristic(ROC) Curve of experimental group, rapid increase of CRP curve and Area under the curve(AUC) value, 0.774, indicate the high accuracy of estimation. 5. In experimental group, sensitivity of CRP, ESR, and Leukocytosis on recovery day were 83%, 17% and 71%. Based on the results of this study, we could conclude that determination of CRP is more useful method to diagnosis and follow-up study of infection than other commonly used variables in oral and maxillofacial region.

• 재활복지
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• v.22 no.1
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• pp.169-194
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• 2018

The aim of this study is to examine changes in swallowing function and quality of life with therapeutic singing-based music therapy for patients with dysphagia. The music therapy program was based on the previous study (Kim, 2010), and designed to improve breathing, phonation, and swallowing functions focusing on laryngeal elevation. Three patients with dysphagia participated in this study and each participant received a total of 11 or 12 individual music therapy sessions and each session was conducted for 30 minutes. In this study, three kinds of measurements were used. First, the measures of maximum phonation time (MPT), fundamental frequency, average intensity, jitter, shimmer, noise to harmonics ratio (NHR) by Praat test, second, laryngeal-diadochokinesis (L-DDK) to investigate laryngeal elevation, and last, the Swallowing-Quality of Life (SWAL-QOL) was measured. These cases have shown improved breathing, phonation, swallowing function, and the scores of SWAL-QOL in all of the patients. It suggests that this music therapy intervention was effective on laryngeal elevation, and the music intervention with therapeutic singing can be effectively implemented in further research for patients with dysphagia.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.4
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• pp.324-330
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• 2018

In order to produce a stable denture for severe alveolar bone loss area, it is not only important that .0a suitable occlusion is established but also to consider compatibility with the surrounding muscle to form a suitable polished surfaces. Neutral zone is defined as a potential area where the neuromuscular system of the tongue, cheeks and lips is balanced can be determined through the neutral zone impression technique. And if artificial teeth are aligned within the neutral zone and the polished surface follows the anatomical form of the dynamic muscle, higher stability and retention of the denture may be obtained through coordination with the surrounding muscle tissue. This case is being reported since the concept of the neutral zone was applied to a patient with severely atrophic residual alveolar ridge and the result was clinically satisfactory in both function and aesthetics.

• Journal of Korean society of Dental Hygiene
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• v.22 no.5
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• pp.315-321
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• 2022

Objectives: Although the number of clinics offering temporomandibular joint (TMJ) physical therapy has been increasing to help with its treatment, the scope of dental physiotherapy reflected in the dental hygienist curriculum is very limited. This study aims to survey the status of dental physiotherapy work and the need for educating dental hygienists. Methods: An online community platform was used to survey 140 dental hygienists working in clinical dental hospitals. The survey included questions about general characteristics, the experience of dental physiotherapy work, the importance of physiotherapy work performance, and the need for physical therapy education for dental hygienists. Results: Half of the study participants had prior experience working in dental physiotherapy. Out of 140 participants, 88.6% agreed with the opinion that 'physical therapy work is important or that it will become important'. Furthermore, 84.3% agreed that 'physical therapy education is necessary for dental hygienists'. Even dental hygienists without physical therapy experience (50.7%) believed that related education would be necessary because of the importance of physical therapy work in dentistry. Conclusions: This study suggests the need for education in dental physiotherapy to help dental hygienists effectively perform clinical tasks.

• Journal of Oral Medicine and Pain
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• v.36 no.2
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• pp.131-137
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• 2011

Current Perception Threshold (CPT) using Neurometer($Neurometer^{(R)}$ CPT/C) is thought as one of easy and noninvasive QST(qunatitative sensory testing) tools for A${\beta}$, A${\delta}$ and C fibers within a relatively short time. However, conflicts about its reliability still exist. This study aimed to evaluate the reliability of CPTs evaluation and find a way to increase its reliability. Two examiners separately tested CPTs at each side of the mandibluar nerve areas for ten healthy male adults (average age of 22.4 years) three times with an intervals of a week during three weeks. Mean CPTs were compared between the right and left sides of the mandibular nerve area and between the three examinations on the each side. While CPTs at 2000 Hz(A${\beta}$ fiber) showed statistically significant side differences in all three examinations (p<0.05), significant side difference was found in only one examination at 250 Hz(A${\delta}$ fiber) and no difference at 5 Hz(C fiber). Comparing CPTs on the each side of the mandibular nerve area, all examinations at all sensory nerve fibers showed the least CPTs at the 1st examinations. CPTs at 250 Hz(A${\delta}$ fiber) and 5 Hz(C fiber) were significantly different between the first and the following examinations (p<0.05) and there was no significant difference between 2nd and 3rd examinations. The results of this study indicated that CPTs at 250 Hz(A${\delta}$ fiber) and 5 Hz(C fiber) are reliable but CPTs at 2000 Hz(A${\beta}$ fiber) is not appropriate for evaluation of side differences in the mandibular nerve area. In addition, it is suggested that repeated examination be helpful to increase reliability of the CPT evaluation.

• Journal of Korean Dental Hygiene Science
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• v.6 no.2
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• pp.13-23
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• 2023

Background: The purpose of this study was to examine the differences in the formation of dental hygienist images based on the pathways of obtaining occupational information and to establish a foundation for the correct perception and positive promotion of the dental hygienist profession. Methods: A survey was distributed to 305 college preparatory students in the metropolitan area. The questionnaire consisted of 34 items, including general characteristics(3 items), pathway-related questions(3 items), dental hygienist image-related question(2 1items), application-related questions(2 items), and admission-related questions(5 items). The images of dental hygienists based on general characteristics, perception pathways, and admission were analyzed using the Mann-Whitney U test and Kruskal-Wallis test. Results: The survey results from all participants showed that the overall image of dental hygienists was 3.75 points. Personal image scored the highest at 4.18 points, while social image was the lowest at 3.20 points(p<0.05). The overall image of dental hygienists was higher for the 'online' group (3.88) compared to the 'offline' group, and statistically significant differences were observed among groups in overall, personal, and professional images(p<0.05). The overall image of dental hygienists was higher for those who learned offline (3.87), and the only significant difference between groups was seen in the personal image. When it came to admission, the 'admitted' students gave a higher overall score (4.00) compared to 'non-admitted' students (3.64), with significance found in all areas except for social image (p<0.05). Conclusion: It is believed that effective utilization of online pathways can inform more people about the importance and expertise of dental hygienists, thereby contributing to promoting oral health and enhancing the perception of the profession. Properly valuing and educating about the role of dental hygienists through promotion and education can help improve the image of the profession.