• 치과방사선
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• 제20권2호
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• pp.265-276
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• 1990

가격 5마리의 하악에 치근단부위 병소 60례와 해면골내 병소 60례를 다양한 크기의 bur로 형성한 후 관전압을 변화시켜 촬영한 방사선 사진을 육안적으로 판독하고 농도계로 분석하여 다음과 같은 결론을 얻었다. 1 흑화도가 일정한 경우 65-85kVp범위내의 관전압 변화는 크기가 같은 골내병소의 판독에 영향을 미치지 않았다(P>0.05). 2 병소가 2번 bur이하의 작은 크기일 때 1번 bur병소에 대한 2번 bur병소의 판독은 치근단 병소는 80kVp 이상의 관전압에서 판독이 용이하였으며 (P<0.05), 해면골내 병소는 75kVp이하의 관전압에서 판독이 용이하였다.(p<0.05) 3. 해면골내 한정된 병소는 치밀골을 포함한 병소와 육안적 판독의 차이가 있었으나(p<0.05). 해면골과 치밀골간의 경계부를 포함한 병소와는 육안적 판독의 차이가 없었다. (p>0.05). 4. 농도계로 분석한 결과 육안적 판독점수가 같았던 경우에도 농도계 계측치는 차이가 있었으며, 0.15-1.66㎜정도의 aluminum등 가치차이가 있어야 육안적으로 병소판독이 가능하였다.

• 치과방사선
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• 제22권1호
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• pp.97-108
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• 1992

The author obtained 120 oblique-lateral transcranial radiograms by two projection methods from 30 subjects with clinically normal TMJ. The relative position of the condyle within the articular fossa and the quality of the radiographic images were compared in the standardized and individualized radiographic groups. The results were as follows: 1. The condylar position in the individualized radiographic group was more posterior than that in the standardized radiographic group (P<0.001). 2. The horizontal angle between the long axis of condyle and intermeatal line in the individualized group ranged from 0° to 31° (14.38°±7.55°), and the highest prevalence was found between 15 and 19° 3. The individualized group showed prominent radiopaque shadow of the anterior condylar border; the image detail was superior in the standardized group to that of the individualized group (P<0.05).

• Imaging Science in Dentistry
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• 제46권4호
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• pp.239-244
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• 2016

Purpose: The aim of this study was to investigate the use and acceptance of digital radiographic examinations by Brazilian dental practitioners in daily practice and to evaluate the advances that have occurred over the past 5 years. Materials and Methods: Dental practitioners enrolled in extension courses at the Piracicaba Dental School, University of Campinas, Brazil, responded to a self­administered questionnaire in the years 2011 and 2015. They were asked about sociodemographic factors and their knowledge and use of digital radiographic examinations. Descriptive analysis was performed, as well as the chi-square and Fisher exact tests, with a significance level of 5% (${\alpha}=0.05$). results: A total of 181 participants responded to the questionnaire in the years 2011 and 2015. Most of the respondents worked in private practice, had graduated within the last 5 years, and were between 20 and 30 years old. In 2011, 55.6% of respondents reported having ever used digital radiographic examinations, while in 2015 this number increased significantly to 85.4% (p<.0001), out of which 71.4% preferred it to conventional images. Moreover, 21.4% of respondents reported having used digital radiographic examinations for more than 3 years. A significant increase in use of intraoral digital radiography (p = 0.0316) was observed in 2015. In both years, image quality and high cost were indicated, respectively, as the main advantage and disadvantage of digital radiographic examinations. conclusion: This study showed that digital radiology has become more common in Brazil over the past 5 years. Most of the Brazilian dental practitioners evaluated in 2015 used digital radiographic examinations.

• Imaging Science in Dentistry
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• 제43권3호
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• pp.179-184
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• 2013

Purpose: X-ray exposure should be clinically justified and each exposure should be expected to give patients benefits. Since dental radiographic examination is one of the most frequent radiological procedures, radiation hazard becomes an important public health concern. The purpose of this study was to investigate the attitude of Korean dentists about radiation safety and use of criteria for selecting the frequency and type of radiographic examinations. Materials and Methods: The study included 267 Korean dentists. Five questions related to radiation safety were asked of each of them. These questions were about factors associated with radiation protection of patients and operators including the use of radiographic selection criteria for intraoral radiographic procedures. Results: The frequency of prescription of routine radiographic examination (an example is a panoramic radiograph for screening process for occult disease) was 34.1%, while that of selective radiography was 64.0%. Dentists' discussion of radiation risk and benefit with patients was infrequent. More than half of the operators held the image receptor by themselves during intraoral radiographic examinations. Lead apron/thyroid collars for patient protection were used by fewer than 22% of dental offices. Rectangular collimation was utilized by fewer than 15% of dental offices. Conclusion: The majority of Korean dentists in the study did not practice radiation protection procedures which would be required to minimize exposure to unnecessary radiation for patients and dental professionals. Mandatory continuing professional education in radiation safety and development of Korean radiographic selection criteria is recommended.

• Imaging Science in Dentistry
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• 제40권4호
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• pp.165-169
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• 2010

Purpose : To survey the radiographic examination protocol for lateral cephalometric radiographic examinations and to measure their patient doses in Korea and to compare the dose according to the size of hospital, the type of image receptor system, and the installation duration. Materials and Methods : The radiographic examination protocols (kVp, mA, and exposure time) for lateral cephalometric radiography were surveyed with 61 cephalometric radiographic equipments and their patient dose-area product (DAP) measured with a DAP meter (DIAMENTOR M4-KDK, PTW, Freiburg, Germany) for 51 cephalometric radiographic equipments. The radiographic examination protocols and patient doses were compared according to the size of hospital (university dental hospital, dental hospital, and dental clinic), the type of image receptor system (film-based, DR and CR type) and the installation duration, respectively. SPSS 12.0.1 for Windows (SPSS Inc., Chicago, USA) was used for independent t-test and ANOVA test. Results : The average protocols were 77.0 kVp, 12.7 mA, 6.2 second for cephalometric radiography. The average patient dose (DAP) was $128.0mGy\;cm^2$ and 3rd quartile dose (DAP) $161.1mGy\;cm^2$ for cephalometric radiography for adult male. There was no statistically significant difference at average patient DAP according to the size of hospital, the type of image receptor system, and the installation duration, repectively. Conclusion : The average patient dose was $128.0mGy\;cm^2$ and the third quartile patient dose $161.1mGy\;cm^2$ for lateral cephalometric radiography for adult male in Korea.

• 치과방사선
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• 제22권2호
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• pp.339-348
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• 1992

The purpose of this study was to evaluate the correlationship between histopathologic types of ameloblastoma and their radiographic appearances. The materials for this study consisted of 106 patients diagnosed as ameloblastoma both radiographically and histologically. The obtained results were as follows: 1. The incidence of ameloblastoma in male(60cases, 56.6%) was slightly higher than that in female (46 cases, 43.4%). The average age was estimated as 30.7 years with a range from 6 to 76 years. The second decade revealed the highest rate. 2. 106 ameloblstomas were histopathologically classified as 36 unicystic, 28 plexiform, 20 follicular, 14 acanthomatous, 7 granular cell, and 1 basal cell ameloblastoma. 3. Unilocular, soap-bubble appearance and scalloped margin were the radiographic appearances frequently seen in unicystic ameloblastoma. The predominant radiographic appearance of plexiform ameloblastoma showed unilocular radiolucency with scalloped margin. 4. 19.8%, 21 cases of ameloblastoma in this study showed containing tooth in their tumor mass by radiography. 5. Root resorption occured in 37 cases(34.9%) and tooth displacement in 7 cases(6.6%). Root resorption and tooth displacement occured in same patient were 24 cases(22.6%). 6. Recurrence occured in 21.7% and average year between initial treatment and recurrence were 2 years.

• 한국전문물리치료학회지
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• 제20권2호
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• pp.46-51
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• 2013

The purpose of this study was to investigate the reliability and validity of goniometer measurements of the hallux valgus angle (HVA) compared to radiographic measurements, which are the current standard. Twenty subjects (10 female, 10 male) were recruited for this study (40 feet). The HVA of the subjects was measured using goniometer and radiographic measurement. In three trials, measurements were taken of each subject by two examiners using goniometer and radiographic measurements using radiography in a standing position. The reliability of the measurements was investigated using intraclass correlation coefficients (ICC(3,1)), and the validity was tested using the Pearson product-moment correlation coefficient and an independent t-test. The intra-rater reliability of left and right HVAs were poor (ICC=.409 and .341, respectively). The inter-rater reliability of left and right HVAs were poor and moderate (ICC=.303 and .501, respectively). Left and right HVAs measured using goniometer and radiographic measurements were also poor and moderate (Pearson r=.246 and .544, respectively). These results suggest that goniometer measurements of the HVA are inaccurate and have unacceptable validity compared to radiographic measurements.

• 치과방사선
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• 제17권1호
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• pp.233-248
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• 1987

The author studied the effect of periapical bone loss on radiographic interpretation by using a dry adult human mandible. Artificial bony lesions were created at the apices of two mandibular second molars and four mandibular bicuspids. The jaw was stabilized and various artificial lesions were radiographed under ideal circumstances. Radiographic pictures were recorded and compared with the size of the actual lesions. The obtained results were as follows: 1. The size of actual lesions were always larger than their radiographic pictures. 2. The size of actual lesion had a greater discrepancy in the molar area where the cortical plates were havier, but the lesions in the bicuspid areas were only slightely larger than their radiographic pictures, and in these areas the cortical plates were quite thin. 3 Periapical lesions located in cancellous bone did not appear on a radiograph, regardless of the size of the created lesion, but when the junctional bone was involved or the cortical plate was perforated, the definite bone destructive change was observed on the roentenogram. 4. Removal of the entire buccal or lingual plate did not affect the trabecular pattern of bone on the roentgenogram. 5. When the cancellous bone and junctional bone were removed simultaneously, altered trabecular patterns were observed on the roentgenogram.

• 치과방사선
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• 제13권1호
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• pp.97-105
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• 1983

For the assessment of changes in the bone architecture of the maxilla and mandible in renal osteodystrophy, 31 chronic renal failure patients who were undergoing hemodialysis therapy were selected. They were evaluated through clinical oral examination, radiographic and biochemical examination. The results were as follows: 1. In 17 cases (54.8%), there were evidences of bony change in jawbone. 2. The most common dental radiographic finding was decreased bone density (14 cases, 45.2%). 3. The second most common dental radiographic finding was total or partial loss of lamina alveolar dura (11 cases, 35.5%). 4. The third most common dental radiographic finding was total or partial loss of inferior canal wall (8 cases, 25.8%). 5 cases showed evidences of bony change only in jawbone, and 5 cases only in hand, and 12 cases in both. 6. Serum creatinine, urea nitrogen and alkaline phosphatase values in hemodialysis group were much higher than in control group. 7. There were statistically significant correlation between bone density and lamina dura, and inferior alveolar canal wall.

• 치과방사선
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• 제19권1호
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• pp.151-159
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• 1989

The author has studied radiographic bony cnages of mandibular condyle head in temporomandibular disorder patients using Oblique lateral transcranial projection, Orthopantomography, and Tomography. The bony change types and the frequencies of occurrence and the incidences of bony changes in three different radiographic techniques were examined. The coincidences of bony change types between the Oblique lateral transcranial projection and the lateral part of Tomogram, the Orthopantomogram and the medial part of Tomogram were also examined. The results were as follows: 1. The mean age of patients was 31.7 years and under 40 years were 24 patients, women werw 27 patients, men were 4patients. 2. The observable case of bony changes in all three radiographic techniques were 19 cases (50%) of 38 cases and the observable cases of bony changes in only Tomography were 5 cases(13.2%) 3. The most frequent radiographic bony change type was osteophyte and next orders were flattening, erosion, concavity. 4. The positional incidences of bony change in Tomogram were 31 cases in lateral part and 27 cases in central part. 5. The coincidence of bony change types between the Oblique lateral transcranial projection and the lateral part of Tomogram was 80%, and the coincidence between the Orthopantomogram and the medial part or Tomogram was 76.0%.