• 치위생과학회지
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• 제11권3호
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• pp.155-161
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• 2011

본 연구는 치근단 필름 촬영에 있어서 촬영법에 따른 실책율을 살펴봄으로써 향후 효율적인 촬영기술 습득과 학생의 지도를 위한 기초 자료를 얻고자 시행되었다. 2009년 3월부터 2010년 12월까지 D 보건대학 및 S 보건대학 치위생과 학생들을 대상으로 촬영한 필름 14,402매를 분석하고, 등각촬영법과 평행촬영법의 촬영 실습수업을 이수한 학생 263명을 대상으로 현상과정에서 가장 어려웠던 점에 관한 설문조사를 실시하여 다음과 같은 결과를 얻었다. 1. 등각촬영법으로 촬영한 경우 상 하악 모두 대구치부에서 실책율이 가장 높았다. 2. 평행촬영법으로 촬영한 경우 상악에서는 소구치부, 하악에서는 대구치부에서 실책율이 가장 높았다. 3. 촬영기술상의 실책은 등각촬영법과 평행촬영법 모두 필름위치의 부정확이 가장 높게 나타났으며, 등각촬영법이 평행촬영법에 비해 실책율이 높게 나타났다. 4. 현상기술상의 실책은 등각촬영법과 평행촬영법 모두 어두운 상과 밝은 상이 가장 높게 나타났으며, 등각 촬영법이 평행촬영법에 비해 실책율이 높게 나타났다. 5. 학생들은 현상과정에서 현상의 정도를 파악하는 것을 가장 어려워하는 것으로 나타났다. 이상의 결과로 살펴볼 때, 치근단 촬영 시 실책율을 줄이기 위해서는 구강 내 형태학적, 해부학적 구조의 이해가 필요하며, 충분한 시간을 가지고 여러 번 반복 촬영하여 숙련도를 높이는 것이 중요하다고 생각된다.

• 치과방사선
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• 제28권2호
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• pp.471-489
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• 1998

For the successful endodontic treatment, root canal should be cleaned thoroughly by accurate mechanical and chemical canal preparation and sealed completely with canal filling material without damaging the periapical tissues. The accuracy of the root canal length measurement is a prerequisite for the success of the endodontic treatment, and the root canal length is often determined by the standard periapical radiographs and digital tactile sense. In this study, the accuracy and the clinical usefulness of Digora/sup (R)/, an intraoral digital imaging processor and the conventional standard radiographs were compared by measuring the length from the top of the file to the root apex. 30 single rooted premolars were invested in a uniformly sized blocks and No.25 K-file was inserted into and fixed in each canal. Each block was placed in equal distance and position to satisfy the principle of the bisecting angle and paralleling techniques and Digora/sup (R)/ system's image and standard periapical radiographs were taken. Each radiograph was examined by 3 different observers by measuring the length from top of the file to the root apex and each data was compared and analyzed. The results were as follows; 1. In the bisecting angle technique, the average difference between the Digora/sup (R)/ system and standard periapical radiograph was 0.002 mm and the standard deviation was 0.341 mm which showed no statistically significant difference between the two systems(p>0.05). Also, in the paralleling technique, the average difference between these two system was 0.007 mm and the standard deviation was 0.323 mm which showed no statistically significant difference between the two systems(p>0.05). 2. In Digora/sup (R)/ system, the average difference between the bisecting angle and paralleling technique was -0.336 mm and the standard deviation was 0.472 mm which showed a statistically significant difference between the two techniques(p<0.05). Also, in the standard periapical radiographs, the average difference between the bisecting angle and paralleling technique was 0.328 mm and the standard deviation was 0.517 mm which showed a statistically significant difference between these two techniques(p<0.05). 3. In Digora/sup (R)/ system and the standard periapical radiographs. there was a statistically significant difference between the measurement using the bisecting angle technique and the actual length(p<0.05), But there was no statistically significant difference between the measurement using the paralleling technique and the actuallength(p>0.05). In conclusion. the determination of the root canal length by using the Digora/sup (R)/ system can give us as good an image as the standard periapical radiograph and using the paralleling technique instead of the bisecting angle technique can give a measurement closer to the actual canal length. thereby contributing to a successful result. Also. considering the advantages of the digital imaging processor such as decreasing the amount of exposure to the patient. immediate use of the image. magnification of image size. control of the contrast and brightness and the ability of storing the image can give us good reason to replace the standard periapical radiographs.

• 치위생과학회지
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• 제4권3호
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• pp.97-102
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• 2004

구내표준방사선사진의 촬영에 있어서 촬영법에 따라 어떤 실책을 얼마나 범하는지를 파악하여 앞으로의 학생지도에 필요한 자료를 얻고자 D보건대학 치위생과 학생들을 대상으로 수업한 결과 필름 3251매를 분석하고, 등각촬영법과 평행촬영법의 촬영실습수업을 이수한 학생 120명을 대상으로 설문조사를 하여 아래와 같은 결과를 얻었다. 1. 등각촬영법으로 촬영한 경우에는 상 하악 모두 견치부에서 실책률이 가장 높았다. 2. 평행촬영법으로 촬영한 경우에는 상 하악 모두 소구치부에서 실책률이 가장 높았다. 3. 촬영기술상의 실책은 상의 연장이 가장 빈도가 높았다. 4. 실책률과 왜곡량 모두 평행촬영법에 비해 등각촬영법에서 높게 나타났다. 5. 필름처리과정에서의 실책은 저현상이 가장 빈도가 높았다. 6. 학생들은 등각촬영법에서는 중심방사선의 수직각 조절을, 평행촬영법에서는 필름고정기구를 구강내에 고정시키는 것을 가장 어렵게 느끼고 있었다. 7. 학생들은 현상과정에서는 현상정도 파악을 가장 어려워하는 것으로 나타났다. 이상의 결과를 종합해 볼 때 구내표준촬영법을 익힘에 있어서 학생들은 수직각조절 미숙으로 인한 실책을 가장 많이 범하며, 현상과정에서 현상정도 파악을 가장 어려워하는 것으로 나타났다. 따라서 학생들이 실책을 줄이고 수면 효율을 높이기 위해서는 해부학적 구조를 충분히 이해하고 공간적인 개념을 가지고 접근할 수 있도록 하는 지도와 함께 각자의 기준을 설정할 수 있도록 개인의 선행 학습 수준에 맞는 1:1 지도가 요구된다. 이를 위해서는 충분한 시간과 보조인력의 확충이 필요하다.

• 치과방사선
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• 제20권2호
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• pp.315-333
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• 1990

This study was performed to measure the skin absorbed doses from full mouth standard intraoral radiography (l4 exposures) in bisecting angle and paralleling techniques. Thermoluminescent dosimeters were used in a phantom. Circular tube collimator(60㎜ in diameter, 20㎝ in length) and rectangular collimator(35㎜ × 44㎜, 40㎝ in length) were set for bisecting angle and paralleling techniques respectively. All measurement sites were classified into 8 groups according to distance from each point of central rays. The results were as follows: 1. The skin absorbed doses from the paralleling technique were significantly decreased than those from the bisecting technique in both points at central ray and points away from central ray. The percentage rates of decrease were greater at points away from central ray than those at central ray. 2. The skin absorbed doses at the lens of eye, parotid gland, submandibular gland and thyroid region were significantly decreased in paralleling techniuqe, but those of the midline of palate remained similar in both techniques. 3. The highest doses were measured at the site 20mm above the point of central ray for the mandibular premolars in bisecting angle technique and at the point of central ray for the mandibular premolars in paralleling techniques. The lowest doses were measured at the thyroid region in both techniques.

• 한국치위생학회지
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• 제12권5호
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• pp.987-997
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• 2012

Objectives : This study was carried out in order to obtain basic data for students' efficient acquirement and instruction of radiography technology in the future by surveying dental hygiene students' recognition of periapical radiography. Methods : This study carried out a questionnaire survey targeting dental hygiene students from December 2009 to December 2010, and obtained the following results. Results : 1. As a result of examining recognition on periapical radiography, the bisecting angle technique was indicated to be averagely $3.84{\pm}0.566$ points. The paralleling technique was indicated to be $2.66{\pm}0.701$ points. 2. As a result of examining about problems given the bisecting angle technique, what had been most difficult given the bisecting angle technique was indicated to be the highest in cone positioning with 34.2%. The most difficulty given deciding on the X-ray vertical-angel irradiation direction was indicated to be the highest with 66.9% in adjusting the cone direction on the virtual bisector. 3. As a result of examining about problems given the paralleling technique, what had been most difficult in the process of the paralleling technique was indicated to be the highest with 56.7% in fixing the film immobilization device inside the mouth. Conclusions : Examining the above results, it is considered that there is a need of understanding morphological and anatomical structure inside the mouth in order to reduce the mistake rate given the periapical radiography, and that it is important to increase skill level by repetitively shooting several times with having enough time.

• 치과방사선
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• 제16권1호
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• pp.103-112
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• 1986

75명의 치과대학 4학년생들이 촬영한 300예의 구내전악표준방사선사진들을 촬영법과 필름의 유지법에 다라 필름을 피촬영자의 엄지나 검지로 유지하고 등각법으로 촬용한 경우 (Ⅰ군), 필름을 Rinn Sanp-A-Ray 기구로 유지하고 등각법으로 촬영한 경우 (Ⅱ군), 필름을 Rinn XCP기구로 유지하고 Short cone에서 평행법으로 촬영한 경우(Ⅲ군), 필름을 Rinn XCP기구로 유지하고 Long cone에서 평행법으로 촬영한 경우(Ⅳ군)으로 분류하여 75예의 구내전악표준방사선사진으로 구성된 각 군의 재촬영을 조사하여 각 군에서 가장 많이 나타난 실책의 종류와 부위, 그리고 구내전악표준방사선사진 1회당 평균재촬영매수에 대해 아래의 결과를 얻었다. Ⅰ군 : Incorrect film placement(47.8%)와 상악 견치부(26.9%)였으며 0.89매였다. Ⅱ군 : Incorrect film placement(44.0%)와 상악 대구치부(28.6%)였으며 1.12매였다. Ⅲ군 : Incorrect film placement(79.1%)와 상악 대구치부(32.0%)였으며 2.05매였다. Ⅳrns : Incorrect film placement(67.7%)와 상악 대구치부(30.7%)였으며 1.69매였다. 평균재촬영매수에서는 같은 촬영법인 Ⅰ군과 Ⅱ군간에서와, Ⅲ군과 Ⅳ군간에서는 유의한 차가 나타나지 않았으나 (P>0.05), 등각촬영법의 군 (Ⅰ＋Ⅱ)보다 평행촬영법의 군(Ⅲ＋Ⅳ)에서 0.86매 많았다 (P<0.01)

• 한국치위생학회지
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• 제6권3호
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• pp.203-218
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• 2006

The purpose of this study was to measure dental hygienists' perception of the usefulness of clinical practice training. A total of 195 dental hygienists participated in the study. The findings of the study were analyzed according to age, the type of hospitals where respondents were working, experience in clinical practices and educational level as follows: 1. There were statistically significant differences in perception of the usefulness of the practice of amalgam filling preparation performed for dental operation among subjects at different ages (p<.01). 2. There were statistically significant differences in perception of the usefulness of the practice of paralleling technique(p<.001), the practice of amalgam filling preparation(p<.01) and the practice of trauma treatment preparation(p<.05) among subjects working at different clinics 3. Significant differences were observed in perception of the usefulness of the practice of sterilization(p<.05), the practice of suction(p<.05), the practice of history taking preparation (p<.01) and the practice of halitosis patient management preparation(p<.05) among subjects with different years of experience in clinical practices. 4. Significant differences were found in perception of the usefulness of the practice of paralleling technique among subjects with different education levels. The findings of the study suggest the need for strengthening education programs for clinical training content and practices which subjects considered important for their job. At the same time, the study emphasizes the need for developing training programs designed to produce dental hygiene preceptor who can provide dental hygienists with practical clinical training in cooperation with college and dental clinics.

• 치과방사선
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• 제25권2호
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• pp.297-308
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• 1995

This study was designed to measure the absorbed dose to organs of special interest from full mouth with intraoral film(l4 films) and to compare the five periapical techniques. Thermoluminescent crystals(TLD-100 chip) were located in brain, orbit, bone marrow of mandibular ramus, bone marrow of mandibular body, bone marrow of 4th cervical spine, parotid gland, submandibular gland and thyroid gland. X -ray machine was operated at 70kVp and round collimating film holding device(XCP) and rectangular collimating film holding device(Precision Instrument) were used. The distance from the X-ray focus to the open end of the collimator was 8 inch, 12 inch and 16 inch. The results were as follows : 1. The absorbed dose was the highest in bone marrow of mandibular body(5.656mGy) and the lowest in brain (0.050mGy). 2. Generally, the lowest absorbed dose was measured from 16 inch cylinder, rectangular collimating film holding device with paralleling technique. But, in bone marrow of mandibular body and the floor of mouth, the highest absorbed dose was measured from 12 inch cylinder, rectangular collimating film holding device with paralleling techniques. 3. Comparing of five intraoral radiographic techniques, it was appeared statistically significant reduction of the absorbed doses measured with rectangular collimating film holding device compared to XCP film holding device (P<0.05). 4. No statistically significant reduction in the absorbed dose was found as cylinder length was changed(P>0.05).

• 한국치위생학회지
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• 제11권5호
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• pp.783-790
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• 2011

Objectives : The purpose of this study was to examine students' difficulties in the process of oral radiography practice, to raise awareness of the importance and necessity of oral radiography and decipher, and to provide some information on effective ways of oral radiography practice. Methods : The subjects in this study were 285 dental hygiene students at K college, who included 153 sophomores and 132 graduates-to-be from June to November, 2010. Results : 1. The parts of the anatomy structure that they found it most difficult to decipher were maxillary molar(25.3%) and lower molar(22.1%). 2. They made during oral radiography was an improper film positioning(35.1%). 3. The part of bisecting technique was adjusting vertical and horizontal angles(53.0%). 4. The part of paralleling technique was positioning XCP in the oral cavity(44.2%). 5. The part of bite-wing technique was adjusting vertical and horizontal angles(38.2%). 6. The part of occlusion technique was positioning film and tube head(36.5%). 7. The part of panorama technique was finding out program setting(42.5%). Conclusions : The findings of the study indicated that in terms of anatomy structure decipher, it's especially difficult to decipher maxillary molar and lower molar, and that film positioning was difficult to do in the process of oral radiography. What difficulties they faced in applying each kind of oral radiography techniques and which part of the oral cavity they found it hard to radiograph were analyzed as well in this study. Given the findings of the study, more intensive practice is required to help students to acquire accurate oral radiography techniques to ensure their successful job performance in the future.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1015-1017
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• 2002

This is the study on static excitation system of synchronous generator of large capacity in new model, which was developed by KEPRI using triple redundant digital method, associate three bridges of thyristor phase controlled rectifier. This paper will discuss the design conception and the application results of system which includes the power control devices(thyristors, GTO) and power excitation potential transformer. The multi-paralleling thyristor bridge converters of N+1 method have firing circuit. The initial product manufactured by proposed design in the study is in commercial operation, completing installation and commissioning in 400MW Thermal Power Plant. The performance test is done in practical technique.