• 한국치위생학회지
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• 제16권2호
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• pp.215-224
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• 2016

Objectives: The purpose of the study was to investigate the related factors of performance of radiation safety management in dental hygienists. Methods: A self-reported questionnaire was completed by 183 dental hygienists using dental radiography in 110 dental clinics in G area by convenience sampling methods. The questionnaire consisted of general characteristics of the subjects, radiation-related characteristics, and performance and management of radiation safety. Results: Performance score of radiation safety management was $35.71{\pm}12.49$ in dental hygienists. The performance score of radiation safety management were associated with sex, numbers of dental hygienists, the average numbers of admitted patients per day, the total clinical experience, existence of manual for radiation safety management and perceived need for education of radiation safety management. Conclusions: The performance score was relatively low. The performance score was associated with radiation safety manual and safety equipment. The preparation of radiation protective environment and equipment will improve the performance of radiation safety management in dental hygienists.

• Imaging Science in Dentistry
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• 제34권1호
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• pp.25-30
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• 2004

Purpose: Several panoramic indices have been suggested to assess bone quality from the morphology and width of mandibular cortex on panoramic radiography. The purpose of this study was to compare dental implant failure group with control group in panoramic mandibular index (PMI), mandibular cortical index (MCI), and gonion index (GI) and to determine the effect of these panoramic indices on dental implant failure. Materials and Methods: A case-control study was designed. Test group (n=42) consisted of the patients who had their implants extracted because of peri-implantitis. Control group (n=139) consisted of the patients who retained their implants over one year without any pathologic changes and had been followed up periodically. They had dental implants installed in their mandibles without bone augmentation surgery from 1991 to 2001. The following measures were collected for each patients: 1) PMI, MCI, and GI were measured twice at one-week interval on preoperative panoramic views; and 2) age, sex, implant length, implant type, installed location, occluding dentition state, and complication were investigated from the chart record. Results: The PMI showed moderate level of repeatability. The intra-observer agreement of MCI and GI were good. There was statistically significant difference in PMI between two groups. There were significant different patterns of distribution of MCI and GI between two groups. Among the panoramic indices, PMI and MCI showed significant correlation with dental implant failure. Conclusion: Panoramic indices can be used as reference data in estimating bone quality of edentulous patients who are to have implants installed in their mandibles.

• Imaging Science in Dentistry
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• 제42권3호
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• pp.183-190
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• 2012

Purpose: The purpose of this study was to investigate the level of clinical image quality of panoramic radiographs and to analyze the parameters that influence the overall image quality. Materials and Methods: Korean dental clinics were asked to provide three randomly selected panoramic radiographs. An oral and maxillofacial radiology specialist evaluated those images using our self-developed Clinical Image Quality Evaluation Chart. Three evaluators classified the overall image quality of the panoramic radiographs and evaluated the causes of imaging errors. Results: A total of 297 panoramic radiographs were collected from 99 dental hospitals and clinics. The mean of the scores according to the Clinical Image Quality Evaluation Chart was 79.9. In the classification of the overall image quality, 17 images were deemed 'optimal for obtaining diagnostic information,' 153 were 'adequate for diagnosis,' 109 were 'poor but diagnosable,' and nine were 'unrecognizable and too poor for diagnosis'. The results of the analysis of the causes of the errors in all the images are as follows: 139 errors in the positioning, 135 in the processing, 50 from the radiographic unit, and 13 due to anatomic abnormality. Conclusion: Panoramic radiographs taken at local dental clinics generally have a normal or higher-level image quality. Principal factors affecting image quality were positioning of the patient and image density, sharpness, and contrast. Therefore, when images are taken, the patient position should be adjusted with great care. Also, standardizing objective criteria of image density, sharpness, and contrast is required to evaluate image quality effectively.

• Imaging Science in Dentistry
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• 제53권3호
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• pp.247-256
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• 2023

The aim of this report is to present a case of chondroblastic osteosarcoma located in the right maxillary premolar region of a 17-year-old female patient. The initial clinical presentation and 2-dimensional (2D) radiographic methods proved inadequate for a definitive diagnosis. However, a cone-beam computed tomography scan revealed a hyperdense, heterogeneous lesion in the right maxillary premolar region, exhibiting a characteristic "sun-ray" appearance. To assess soft tissue involvement, a medical computed tomography scan was subsequently conducted. A positron emission tomography scan detected no metastasis or indications of secondary tumors. T1- and T2-weighted magnetic resonance imaging showed signal heterogeneity within the lesion, including areas of low signal intensity at the periphery. Histological examination conducted after an incisional biopsy confirmed the diagnosis of highgrade chondroblastic osteosarcoma. The patient was then referred to an oncology department for chemotherapy before surgery. In conclusion, these findings suggest that early diagnosis using 3-dimensional imaging can detect chondroblastic osteosarcoma in its early stages, such as before metastasis occurs, thereby improving the patient's prognosis.

• Journal of Periodontal and Implant Science
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• 제42권4호
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• pp.145-145
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• 2012

• 대한치주과학회:학술대회논문집
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• 대한치주과학회 2000년도 제40회 종합학술대회 연제초록
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• pp.136-137
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• 2000

• 구강회복응용과학지
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• 제29권3호
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• pp.249-258
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• 2013

이 연구의 목적은 환자의 머리 위치에 따른 파노라마방사선사진의 수평 및 수직 확대율을 비교 평가하는 것이었다. 직경 4 mm인 금속구를 건조 두개골의 하악 전치부와 우측 대구치부의 치조골 상방에 위치시켰다. 수평 및 수직적 위치의 변화를 재현하기 위해 수직, 수평 이동량을 조절할 수 있는 두개골 고정장치를 이용하여, 전방, 후방, 좌측 및 우측으로 이동시킨 후 파노라마방사선사진을 OP-100D를 이용하여 획득하였다. 촬영된 영상은 DICOM 형식으로 저장되었고, INFINITT PACS software를 이용하여 금속구의 폭과 높이의 평균값을 구하였다. 적절한 위치에서 촬영된 파노라마방사선사진에서 금속구의 수평 확대율은 1.224-1.439였고, 수직 확대율은 1.286-1.345였다. 건조 두개골의 위치 변화에 따른 수평 확대율은 0.798-6.297로 통계적으로 유의한 차이를 보인 반면(P<0.05), 수직 확대율은 1.245-1.418 정도로 수평 확대율에 비해 차이를 보이지 않았다.

• Imaging Science in Dentistry
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• 제50권1호
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• pp.45-52
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• 2020

Purpose: This study was conducted to develop an evidence-based clinical imaging diagnostic guideline for implant planning, taking into account efficacy, benefits, and risks. Materials and Methods: The guideline development process employed the adaptation methodology used for Korean clinical imaging guidelines(K-CIG). Core databases(Ovid-Medline, Ovid-Embase, National Guideline Clearinghouse, Guideline International Network) and domestic databases (KoreaMed, KMbase, and KoMGI) were searched for guidelines. The retrieved articles were analyzed by 2 reviewers, and articles were selected using well-established inclusion criteria. Results: The search identified 294 articles, of which 3 were selected as relevant guidelines. Based on those 3 guidelines, 3 recommendations for implant planning were derived. Conclusion: We recommend radiography or cone-beam computed tomography (CBCT) scanning for individual patients judged to require a cross-sectional image after reading of a panoramic X-ray image and a conventional intraoral radiological image. Various steps should be taken to raise awareness of these recommendations among clinicians and the public, and K-CIG should be regularly reviewed and revised.

• Imaging Science in Dentistry
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• 제34권2호
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• pp.63-67
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• 2004

Purpose: To make a focal trough (image layer) for an average maxillary dental arch of 6-year-old korean in panoramic radiography. Materials and Methods : Phantom for the maxillary dental arch was designed using intercanine width, intermolar width, tooth size, and interdental spacing to record the data of 6-year-old child. The characteristics of pre-corrected panoramic machine (for adult) was evaluated using the phantom, resolution test pattern for margin of the image layer, and metal ball for the center of the image layer. Panoramic image layer of the child was developed by means of decreasing the speed of film-cassette and positioning the phantom backwards, and then the characteristics of post-corrected panoramic machine (for child) were reevaluated. Results: At post-corrected panoramic image layer, beam projection angles at all interdental areas increased for about 2.6-3.8°, the position of the image layer was shifted toward the rotation center for about 2.5 mm at the deciduous central incisior area. The width of image layer decreased at all areas. Conclusion : Increased beam projection angle will reduce the disadvantage of tooth overlap, and the same form between the center of the image layer and dental arch will improve image resolution.

• Imaging Science in Dentistry
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• 제48권2호
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• pp.87-96
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• 2018

Purpose: The present study aimed to evaluate which of the following imaging methods best assessed misfit at the tooth-restoration interface: (1) bitewing radiographs, both conventional and digital, performed using a photostimulable phosphor plate (PSP) and a charge-coupled device (CCD) system; (2) panoramic radiographs, both conventional and digital; and (3) cone-beam computed tomography (CBCT). Materials and Methods: Forty healthy human molars with class I cavities were selected and divided into 4 groups according to the restoration that was applied: composite resin, composite resin with liner material to simulate misfit, dental amalgam, and dental amalgam with liner material to simulate misfit. Radiography and tomography were performed using the various imaging methods, and the resulting images were analyzed by 2 calibrated radiologists. The true presence or absence of misfit corresponding to an area of radiolucency in regions subjacent to the esthetic and metal restorations was validated with microscopy. The data were analyzed using a receiver operating characteristic (ROC) curve, and the scores were compared using the Cohen kappa coefficient. Results: For bitewing images, the digital systems (CCD and PSP) showed a higher area under the ROC curve (AUROC) for the evaluation of resin restorations, while the conventional images exhibited a larger AUROC for the evaluation of amalgam restorations. Conventional and digital panoramic radiographs did not yield good results for the evaluation of resin and amalgam restorations (P<.05). CBCT images exhibited good results for resin restorations(P>.05), but showed no discriminatory ability for amalgam restorations(P<.05). Conclusion: Bitewing radiographs (conventional or digital) should be the method of choice when assessing dental restoration misfit.