• 대한치과보철학회지
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• 제50권3호
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• pp.184-190
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• 2012

연구 목적: 이 연구는 상악 전치부와 하악 구치부 치근단 방사선촬영시 이동형 구내방사선촬영기와 벽걸이 구내방사선촬영기로 촬영한 경우에서 환자의 방사선량을 알아보고자 하였다. 연구 재료 및 방법: 방사선량 측정은 선량 측정용 두경부 마네킨의 23부위에 열형광선량계 소자를 위치시키고 해당 치근단 방사선촬영을 하였다. 열형광선량계 판독기로 흡수선량을 구하였고 방사선 조사된 조직의 비율을 곱하여 방사선 가중선량을 구하였다. 국제방사선방호위원회에서 2007년에 공지한 조직 가중계수를 이용하여 각 방사선촬영의 유효선량을 구하였다. 결과: 환자의 흡수선량은 이동형 구내방사선촬영기로 촬영한 상악 전치부와 이동형 및 벽걸이 구내방사선촬영기로 촬영한 하악 구치부 치근단방사선촬영의 경우 하악체에서 가장 높았다. 유효선량은 상악 전치부 치근단 방사선촬영에서는 이동형 촬영기로 촬영한 경우 $4{\mu}Sv$, 벽걸이 촬영기로 촬영한 경우 $2{\mu}Sv$였고 우측 하악 구치부 치근단 방사선촬영에서는 각각 $6{\mu}Sv$, $2{\mu}Sv$였다. 결론: 벽걸이 구내방사선촬영기보다 이동형 구내방사선촬영기로 촬영한 치근단 방사선촬영에서의 유효선량이 더 많기 때문에 술자는 구내방사선촬영기에 따른 방사선 노출 정도를 충분히 인지하고 이를 사용하여야 한다.

• Restorative Dentistry and Endodontics
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• 제37권3호
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• pp.160-164
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• 2012

Objectives: This study was aimed to investigate the methods to reduce operator's radiation dose when taking intraoral radiographs with portable dental X-ray machines. Materials and Methods: Two kinds of portable dental X-ray machines (DX3000, Dexcowin and Rextar, Posdion) were used. Operator's radiation dose was measured with an 1,800 cc ionization chamber (RadCal Corp.) at the hand level of X-ray tubehead and at the operator's chest and waist levels with and without the backscatter shield. The operator's radiation dose at the hand level was measured with and without lead gloves and with long and short cones. Results: The backscatter shield reduced operator's radiation dose at the hand level of X-ray tubehead to 23 - 32%, the lead gloves to 26 - 31%, and long cone to 48 - 52%. And the backscatter shield reduced operator's radiation dose at the operator's chest and waist levels to 0.1 - 37%. Conclusions: When portable dental X-ray systems are used, it is recommended to select X-ray machine attached with a backscatter shield and a long cone and to wear the lead gloves.

• 치위생과학회지
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• 제15권3호
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• pp.254-258
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• 2015

치과병의원에서 사용하고 있는 이동형 치과 X선 발생장치를 이용하여 두경부 마네킹에 X선을 조사할 때 주변의 공간선량을 측정하고, 동일한 방법으로 고정형 X선 발생장치에 적용하여 측정된 공간선량을 상호 비교하며, 더불어 기기 및 위치별 공간선량을 비교 분석한 결과는 다음과 같다. 이동형 X선 발생장치의 평균 공간선량은 $37.51{\mu}Sv$로 고정형 X선 발생장치의 $10.77{\mu}Sv$보다 매우 높았다(p<0.001). 이동형 X선 발생장치의 기기별 공간선량은 $17.77{\mu}Sv$부터 $68.90{\mu}Sv$까지 큰 차이를 나타냈다(p<0.05). 위치별로는 직전 위치가 $54.14{\mu}Sv$로 가장 높았고, 직우 위치가 $13.60{\mu}Sv$로 가장 낮았으며, 직좌와 직후 위치는 $42.12{\mu}Sv$, $40.18{\mu}Sv$로 유사하였다(p<0.01). 이상의 결과를 통해 이동용 치과 X선 발생장치는 이동 불가능한 환자만을 대상으로 제한적으로 시행하여야 하며, 반드시 환자와 술자 모두 납 방어복을 착용하여 방사선 피폭을 최소화해야 할 것이다.

• Imaging Science in Dentistry
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• 제37권2호
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• pp.65-68
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• 2007

Purpose: To compare the leakage and scattered radiation from hand-held dental X-ray unit with radiation from fixed dental X-ray unit. Materials and Methods: For evaluation we used one hand-held dental X-ray unit and Oramatic 558 (Trophy Radiologie, France), a fixed dental X-ray unit. Doses were measured with Unfors Multi-O-Meter 512L at the right and left hand levels of X-ray tube head part for the scattered and leakage radiation when human skull DXTTR III was exposed to both dental X-ray units. And for the leakage radiation only, doses were measured at the immediately right, left, superior and posterior side of the tube head part when air was exposed. Exposure parameters of handheld dental X-ray unit were 70 kVp, 3 mA, 0.1 second, and of fixed X-ray unit 70 kVp, 8 mA, 0.45 second. Results: The mean dose at the hand level when human skull DXTTR III was exposed with portable X-ray unit $6.39{\mu}Gy$, and the mean dose with fixed X-ray unit $3.03{\mu}Gy$ (p<0.001). The mean dose at the immediate side of the tube head part when air was exposed with portable X-ray unit was $2.97{\mu}Gy$ and with fixed X-ray unit the mean dose was $0.68{\mu}Gy$ (p<0.01). Conclusions: The leakage and scattered radiation from hand-held dental radiography was greater than from fixed dental radiography.

• 한국치위생학회지
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• 제17권6호
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• pp.1053-1065
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• 2017

Objectives: The purpose of this study is to evaluate radiation safety education, knowledge and practice of dental hygienists in using handheld portable intraoral X-ray equipment and to suggest the need for radiation safety education in using handheld portable intraoral X-ray equipment. Methods: We surveyed 223 dental hygienists from July, 2017 to August in the dental clinics of Daejeon, Seoul and Gyeonggi area. Results: Radiation safety educational experience was higher in a year's career (72.9%), than 3 years experience (32.5%) (p<0.05). 82.7% of dental clinic workers took university education for radiation safety education while 55.6% of dental hospital workers took company training (p<0.05). More than 70% of the subjects did not have experience of radiation safety education about using portable intraoral X-ray. Radiation safety knowledge was highest in a year's career (p<0.05). The cumulative dose, radiation sensitivity, and lead defense knowledge were high in all subjects, but knowledge related to scattering radiation and scattering radiation sources was low. Practice of portable intraoral X-ray safety was significantly lower than knowledge. Conclusions: Knowledge of portable intraoral radiography safety is available, but performance is poor. Even with the small amount of radiation exposure, the risk is perceivable. There is a need to actively utilize the provided radiation protection products. In order to do this, efforts should be made to improve knowledge and performance of radiation safety through not only college education but also postemployment training.

• 대한치과의사협회지
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• 제50권7호
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• pp.420-430
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• 2012

Purpose: The purpose of this study was to measure the absorbed dose and to calculate the effective dose for full-mouth periapical radiography using the portable dental x-ray machine and panoramic radiography Material and Method: Thermoluminescent chips were placed at 25sites throughout the layers of the head and neck of a tissue-equivalent human skull phantom. The man phantom was exposed with the portable dental x-ray machine and panoramic unit. During full-mouth periapical radiography the exposure setting was 60 kVp, 2 mA and 0.15 ~ 0.25 seconds, while during panoramic radiography the selected exposure setting was 72 kVp, 8 mA and 18 seconds. Absorbed dose measurements were obtained and equivalent doses to individual organs were summed using ICRP 103 to calculate of effective dose. Result: In the full-mouth periapical radiography, the highest absorbed dose was recorded at the mandible body follow with submandibular glands and cheek. Using panoramic unit, the highest absorbed dose was parotid glands and the following was back of neck and submandibular glands. The effective dose in full-mouth periapical radiography using portable dental x-ray machine was 46 ${\mu}Sv$. In panoramic radiography, the effective dose was 38 ${\mu}pSv$. Conclusion: It was recommended to panoramic radiography for general check in the head and neck area because that the effect dose in the panoramic radiography was lower than the dose in the full-mouth periapical radiography using portable dental x-ray machine.

• Imaging Science in Dentistry
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• 제37권3호
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• pp.149-156
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• 2007

Purpose: The purpose of this study was to measure the absorbed dose and to calculate the effective dose for periapical radiography done by portable intraoral x-ray machines. Materials and Methods: 14 full mouth, upper posterior and lower posterior periapical radiographs were taken by wall-type 1 and portable type 3 intraoral x-ray machines. Thermoluminescent dosemeters were placed at 23 sites at the layers of the tissue-equivalent ART woman phantom for dosimetry. Average tissue absorbed dose and radiation weighted dose were calculated for each major anatomical site. Effective dose was calculated using 2005 ICRP tissue weighted factors. Results: On 14 full mouth periapical radiographs, the effective dose for wall-type x-ray machine was 30 Sv; for portable x-ray machines were 30 Sv, 22 Sv, 36 Sv. On upper posterior radiograph, the effective dose for wall-type x-ray machine was 4 Sv; for portable x-ray machines doses were 4 Sv, 3 Sv, 5 Sv. On lower posterior radiograph, the effective dose for wall type x-ray machine was 5 Sv; for portable x-ray machines doses were 4 Sv, 4 Sv, 5 Sv. Conclusion: Effective doses for periapical radiographs performed by portable intraoral x-ray machines were similar to doses for periapical radiographs taken by wall type intraoral x-ray machines.

• Imaging Science in Dentistry
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• 제48권3호
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• pp.167-176
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• 2018

Purpose: In the age of X-ray computed tomography (CT) and digital volume tomography (DVT), with their outstanding post-processing capabilities, indications for planar radiography for the study of the dentition of ancient Egyptian mummies may easily be overlooked. In this article, the advantages and limitations of different approaches and projections are discussed for planar oral and maxillofacial radiography using portable digital X-ray equipment during archaeological excavations. Furthermore, recommendations are provided regarding projections and sample positioning in this context. Materials and Methods: A total of 55 specimens, including 19 skeletonized mandibles, 14 skeletonized skulls, 18 separate mummified heads, and 4 partially preserved mummies were imaged using portable digital X-ray equipment in the course of archaeological excavations led by the University of Basel in the Valley of the Kings between 2009 and 2012. Images were evaluated by 2 authors with regard to the visibility of diagnostically relevant dental structures using a 4-point grading system(Likert scale). Results: Overall, the visibility of diagnostically relevant dental structures was rated highest by both authors on X-ray images acquired using a dental detector. The tube-shift technique in the lateral projections of mandibular dentition achieved the second-best rating, and lateral projections achieved the third-best rating. Conclusion: Conventional planar digital X-ray imaging, due to its ubiquity, remains an excellent method-and often the only practicable one-for examining the skulls and teeth of ancient Egyptian mummies under field conditions. Radiographic images of excellent diagnostic quality can be obtained, if an appropriate methodology regarding the selected projections and sample placement is followed.

• Imaging Science in Dentistry
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• 제42권1호
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• pp.1-4
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• 2012

Purpose : Hand-held dental x-ray system is a self contained x-ray machine designed to perform intraoral radiography with one or two hands. The issue about its usage as general dental radiography is still in dispute. The aim of the present study was to assess the relationship between the amount of battery charge and the tube voltage in different handheld dental x-ray systems. Materials and Methods : Seven hand-held dental x-ray units were used for the study. Tube voltage was measured with Unfors ThinX RAD (Unfors Instruments AB, Billdal, Sweden) for 3 consecutive exposures at the different amount of battery charge of each unit. The average and the deviation percentage of measured kV from indicated kV of each unit were calculated. Results : Tube voltage of only 1 unit was 70 kV (indicated by manufacturer) and those of the others were 60 kV. Tube voltage deviation percentage from the indicated kV at the fully charged battery was from 2.5% to -5.5% and from -0.8% to -10.0% at the lowest charged battery. Conclusion : Tube voltages of all units decreased as the residual amount of the battery charge decreased. It is suggested that the performance test for hand-held x-ray system should be performed for the minimum residual charged battery as well as the full charged one. Persistent battery charging is suggested to maintain the proper tube voltage of the hand-held portable x-ray system.

• 대한방사선기술학회지:방사선기술과학
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• 제39권4호
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• pp.651-660
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• 2016

최근 인구고령화로 인하여 치과진료 주요대상인 노인층의 검사가 꾸준히 증가하고 있다. 따라서 치과 진단용 엑스선장치 시장도 꾸준히 성장하고 있으며, 동시에 치과용엑스선장치의 허가 심사건수도 증가하고 있다. 의료기기 기술문서는 의료기기의 허가 심사 시 필수로 요구되는 자료이며, 해당 의료기기의 전반적인 항목을 기술해야 하는 만큼 작성자의 업무 이해도 및 전문성이 필요하다. 그러나 국내 의료기기 제조 수입 업체 대부분이 영세하여 의료기기 인 허가 관련 전문 인력의 확보가 쉽지 않아, 이로 인한 기술문서의 부정확한 작성이 증가하고 있다. 이에 따른 심사자의 민원 처리 지연과, 제품의 신속한 시장 진입의 어려움이 발생되고 있다. 특히 치과용구강외엑스선장치, 치과용구강내엑스선장치, 암형전산화단층엑스선촬영장치, 포터블엑스선 촬영장치(이하 치과용엑스선장치)는 식품의약품안전처 기준 규격이 최근에 제정되거나 부재한 품목으로, 의료기기 제조 수입업체에서 시험항목 설정 시 많은 어려움을 겪고 있기에, 개선된 규격이 반영된 치과용엑스선 장치 가이드라인(안)을 개발하여 관련 업체 및 심사자에게 도움을 주고자 한다. 본 연구를 위하여 첫째, 기술문서에 대한 개선된 제도 운영 조사 및 의료기기의 제도 적용에 따른 문서 작성 방법을 검토하였으며, 둘째, 품목별 시장현황을 조사하고, 국내 외 규격을 분석하였으며, 셋째, 기 허가된 제품의 기술문서를 분석하여 품목별 올바른 작성방법과 국제조화된 시험항목, 기준 및 방법을 도출하였다. 마지막으로, 산 연 관 전문가 협의체 회의를 통하여, 공정하고 전문성이 강화된 기술문서 작성 가이드라인(안)을 도출하였다.