• Imaging Science in Dentistry
• /
• v.43 no.3
• /
• pp.179-184
• /
• 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.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.13 no.1
• /
• pp.97-105
• /
• 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.

• Imaging Science in Dentistry
• /
• v.40 no.4
• /
• pp.165-169
• /
• 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.

• Restorative Dentistry and Endodontics
• /
• v.42 no.3
• /
• pp.200-205
• /
• 2017

Objectives: The aim of this in vivo study was to assess the accuracy of 2 third-generation electronic apex locators (EALs), Propex II (Dentsply Maillefer) and Root ZX II (J. Morita), and radiographic technique for locating the major foramen (MF). Materials and Methods: Thirty-two premolars with single canals that required extraction were included. Following anesthesia, access, and initial canal preparation with size 10 and 15 K-flex files and SX and S1 rotary ProTaper files, the canals were irrigated with 2.5% sodium hypochlorite. The length of the root canal was verified 3 times for each tooth using the 2 apex locators and once using the radiographic technique. Teeth were extracted and the actual WL was determined using size 15 K-files under a ${\times}25$ magnification. The Biostat 4.0 program (AnalystSoft Inc.) was used for comparing the direct measurements with those obtained using radiographic technique and the apex locators. Pearson's correlation analysis and analysis of variance (ANOVA) were used for statistical analyses. Results: The measurements obtained using the visual method exhibited the strongest correlation with Root ZX II (r = 0.94), followed by Propex II (r = 0.90) and Ingle's technique (r = 0.81; p < 0.001). Descriptive statistics using ANOVA (Tukey's post hoc test) revealed significant differences between the radiographic measurements and both EALs measurements (p < 0.05). Conclusions: Both EALs presented similar accuracy that was higher than that of the radiographic measurements obtained with Ingle's technique. Our results suggest that the use of these EALs for MF location is more accurate than the use of radiographic measurements.

• Imaging Science in Dentistry
• /
• v.33 no.1
• /
• pp.15-20
• /
• 2003

Purpose : To investigate the reproducibility of the conventional and digital radiographs to determine the depth of approximal root cavities. Materials and Methods : A total of 80 artificial root cavities were prepared in the approximal surfaces of premolars, maxillary and mandibular molars. Standardized radiographs were taken at the baseline (0° horizontal and 0° vertical) and at a horizontal angulation of 10° in both mesial and distal directions. Radiographic cavity depths were measured by both conventional and digital radiographs. Results: At 0° horizontal angulation, no statistically significant differences could be determined between the results of conventionally and digitally determined radiographic depths with respect to the actual cavity depths in all premolar, maxillary, and mandibular molar groups. All conventional and digital radiographic depths at both 10° mesial and distal angulations showed statistically significant increases in depth compared to the actual cavity depths (p < 0.05), with the exception of digital radiographic depth at 10° mesial angulation for premolars. There were no statistically significant differences between conventional and digital radiographic depths for all groups. Conclusion: The present study suggests that both conventional and digital radiographs provide reproducible assessment of the depth of the approximal root cavity. But horizontal X-ray beam movements are likely to result in increase in radiographic cavity depth.

• Imaging Science in Dentistry
• /
• v.40 no.4
• /
• pp.155-158
• /
• 2010

Digital radiographic systems allow the implementation of a fully digital picture archiving and communication system (PACS), and provide the greater dynamic range of digital detectors with possible reduction of X-ray exposure to the patient. This article reviewed the basic physical principles of digital radiographic imaging system in dental clinics generally. Digital radiography can be divided into computed radiography (CR) and direct radiography (DR). CR systems acquire digital images using phosphor storage plates (PSP) with a separate image readout process. On the other hand, DR systems convert X-rays into electrical charges by means of a direct readout process. DR systems can be further divided into direct and indirect conversion systems depending on the type of X-ray conversion. While a direct conversion requires a photoconductor that converts X-ray photons into electrical charges directly, in an indirect conversion, lightsensitive sensors such as CCD or a flat-panel detector convert visible light, proportional to the incident X-ray energy by a scintillator, into electrical charges. Indirect conversion sensors using CCD or CMOS without lens-coupling are used in intraoral radiography. CR system using PSP is mainly used in extraoral radiographic system and a linear array CCD or CR sensors, in panoramic system. Currently, the digital radiographic system is an important subject in the dental field. Most studies reported that no significant difference in diagnostic performance was found between the digital and conventional systems. To accept advances in technology and utilize benefits provided by the systems, the continuous feedback between doctors and manufacturers is essential.

• Imaging Science in Dentistry
• /
• v.49 no.4
• /
• pp.307-315
• /
• 2019

This report describes 3 cases of cleidocranial dysplasia (CCD) and presents relevant findings on long-term follow-up radiographic images of impacted permanent teeth with delayed eruption. Radiographic images of 3 CCD patients were reviewed retrospectively. These images were mainly composed of panoramic and skull radiographs, and the follow-up periods were 3, 13, and 13 years, respectively. The distinct features revealed by the images were described, and the eruption state of impacted permanent teeth was evaluated. The features common to the 3 cases were multiple supernumerary teeth, the presence of Wormian bone, underdevelopment of the maxilla and the maxillary sinus, and clavicular hypoplasia. The eruption of impacted permanent teeth was not observed without proper dental treatment in adult CCD cases, even after long time periods had elapsed. When proper orthodontic force was applied, tooth movement was observed in a manner not significantly different from the general population.

• Imaging Science in Dentistry
• /
• v.39 no.3
• /
• pp.169-173
• /
• 2009

The calcifying odontogenic cyst (COC) is a rare disorder of the jaws and shows various radiographic features. The purpose of this study is to describe the different radiographic appearances of 2 cases of COC. Case 1 was located in the posterior maxilla extending into maxillary sinus, showing unilocular radiolucency with a well-defined margin. Cortical bone expansion and thinning were prominent. Root resorption of adjacent teeth was apparent. Case 2 showed unilocular radiolucency with a calcified material. Calcification was supposed to be dystrophic dental hard structures, detected at the periphery of the lesion. Ghost cell and proliferation of ameloblastoma-like tissues were common features for these two lesions on histopathological findings. This reports presented common and atypical radiographic features of the COC.

• Imaging Science in Dentistry
• /
• v.53 no.1
• /
• pp.35-42
• /
• 2023

Purpose: This study investigated the current dental radiology reporting methods and the recording rate of 10 mandatory reporting items in Korea. Materials and Methods: An original online survey created using Google Forms was distributed to dental practitioners. The survey asked about the participants' age, experience, workplace, use of radiologic equipment, radiology reporting methods, and recording reporting items. Results: In total, 354 responses were analyzed. Radiologic reporting in dental charts was the most commonly used method for each modality. Four out of 10 mandatory items were recorded at a high rate, but the remaining 6 items had substantially lower recording rates, often below 50%. The participants who reported radiographic findings through other separate methods had higher item scores than those who wrote findings in dental charts(P<0.05). Conclusion: Radiologic societies and dental associations should encourage the use of separate reports for radiographic examinations. Education regarding radiology reports and the justification for reporting items should be reinforced in dental schools, training courses on radiology, and the continuing education curriculum.

• The Journal of the Korean dental association
• /
• v.54 no.9
• /
• pp.712-728
• /
• 2016

These days, the clinical course of dental imaging sector has done a lot of implant-related imaging courses, including cone beam CT. In contrast, the general image reading course is not given a lot of opportunities to learn. Therefore, it is imperative that we talk about the general image interpretation that can be read easily applied in a dental clinic. When we see a strange radiographic finding of our patient in the dental clinic, we should first check whether the radiographic finding is a normal finding or a morbidity. If the finding is diagnosed as a morbidity, you should make plans for the appropriate therapy. The most important step is classification between normal state and morbidity. Some lesions may occur without any clinical symptoms. Therefore, we should read all the parts of radiographs, even the patient does not have clinical symptoms.