• Journal of radiological science and technology
• /
• v.33 no.1
• /
• pp.1-10
• /
• 2010

Dental panoramic radiography is an imaging technique which shows the information of teeth, jaws and superficial structures on a single image. In this study, we propose the clinical dose reference for dental panoramic radiography. Dental panoramic radiography is an application which can increase the radiation does of oral cavity. It is very important to study the real condition of management for these panoramic X-ray equipments. Since there was no researches on dental panoramic equipments in domestic and foreign study groups, we measured and analyzed the dose such as effective dose, DAP and DWP of panoramic radiography.

• The Journal of the Korean dental association
• /
• v.44 no.3 s.442
• /
• pp.185-188
• /
• 2006

• Journal of the korean academy of Pediatric Dentistry
• /
• v.39 no.3
• /
• pp.273-279
• /
• 2012

Purpose : This study was aimed to calculate effective dose from cone beam CT and compare effective dose from periapical and panoramic radiography for mesiodens. Materials and Methods : Upper anteiror periapical, panoramic radiography and cone-beam CT were taken for diagnosis of mesiodens. The effective dose were calculated by using an anthropomorphic phantom loaded with thermoluminescent dosimeters at the 23 sites related to sensitive organs. Results : The highest absorbed doses were received by the mandibular body, parotid gland and cheek from periapical, panoramic and cone-beam CT, respectively. The effective doses for periapical, panoramic radiography and cone-beam CT measured 2, 18 and 48 ${\mu}Sv$. Conclusion : Cone-beam CT, although providing additional diagnostic benefits, exposes patients to higher levels of radiation than conventional periapical and panoramic radiography.

• Journal of The Korean Radiological Technologist Association
• /
• v.28 no.1
• /
• pp.347-348
• /
• 2002

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.24 no.2
• /
• pp.317-326
• /
• 1994

Panoramic radiographs of a dry skull were used to evaluate the accuracy of four panoramic dental X-ray systems in determining tooth angulations in the buccal segments. The four machines evaluated were the Philips Oralix Pan DC, the GE panelipse, the SS White panorex 1, and the SS White Panorex 2. Panoramic radiographs were taken at six different patient positions for each machine to evaluate the effects of patient positioning on determining tooth angulations in the buccal segments. All of the machines studied showed a significant correlation between the mean radiographic estimates and the actual measurements regardless of positioning(p<0.05). With correct placement of the skull, the results were analyzed for an error tolerance of +/-3/sup 0/ between the actual measurements and the radiographic estimates for tooth angulation. The SS White Panorex 1 was accurate 74% of the time, the GE Panelipse was accurate 67% of the time, the Philips Oralix Pan DC and the SS White Panorex 2 were accurate 64% of the time. When an error tolerance of +/-5/sup 0/ was permitted, the accuracy was 89% for the SS White Panorex 1 and the GE Panelipse, 85% for the Philips Oralix Pan DC, and 81% for the SS White Panorex 2.

• Journal of the Korean Society of Radiology
• /
• v.7 no.4
• /
• pp.301-305
• /
• 2013

This thesis intends to analyze tooth distortion by mandibular arch form by reproducing existing panorama image and reconstructed panorama image of Cone Beam CT data with the three-dimensional computer program. The diameter of tooth measured in Cone Beam CT's cross-section image and reconstructed panorama was synchronized without any big change from incisors to posteriors. But, panorama showed serious distortion as going to posteriors after showing a little distortion in incisors. The panorama reconstructed for patients' individual arch showed reduced distortion than panoramas used generally. In addition, panorama showed serious distortion from incisors to posteriors and it means that distortion is reduced in reconstructed panorama.

• The korean journal of orthodontics
• /
• v.41 no.4
• /
• pp.255-267
• /
• 2011

Objective: The purpose of this study was to confirm the reliability of a cone beam computed tomography (CBCT)-generated panoramic view based on a CBCT 3D image and to find the most helpful 2D panoramic image compared with CBCT 3D image when examining the mesiodistal tooth axis. Methods: A test model was constructed according to cephalometric norms. The test model was repeatedly repositioned for CBCT and panoramic radiographic imaging. Panoramic radiographs were acquired at each of the following 3 occlusal plane positions: $-5^{\circ}$, $0^{\circ}$, and $+5^{\circ}$. Measurements of mesiodistal tooth axis in CBCT 3D image, CBCT-generated panoramic view, and panoramic radiographs were compared. Results: Compared with the CBCT-generated panoramic view, CBCT 3D image showed significant difference in the mesiodistal tooth axis in the premolars and no significant difference in the mesiodistal tooth axis in the incisors and canines. Mesiodistal tooth axis on the CBCT-generated panoramic view was significantly different from that on panoramic radiographs. Conclusions: CBCT-generated panoramic view can be a useful tool for evaluating mesiodistal tooth axis.

• Journal of the Korean Society of Radiology
• /
• v.7 no.1
• /
• pp.17-24
• /
• 2013

This study estimate radiation biological danger factor by measuring patient's exposed dose and propose the low way of patient's exposed dose in panoramic radiography. We seek correcting constant of OSL dosimeter for minimize the error of exposed dose's measurement and measure the Left, Right crystalline lens, thyroid, directly included upper, lower lips, the maxillary bone and the center of photographing that indirect included in panoramic radiography by using the human body model standard phantom advised in ICRP. In result, the center of photographing's level of radiation maximum value is $413.67{\pm}6.53{\mu}Gy$ and each upper, lower lips is $217.80{\pm}2.98{\mu}Gy$, $215.33{\pm}2.61{\mu}Gy$. Also in panoramic radiography, indirect included Left, Right crystalline lens's level of radiation are $30.73{\pm}2.34{\mu}Gy$, $31.87{\pm}2.50{\mu}Gy$, and thyroid's level of measured exposed dose can cause effect of radiation biological and we need justifiable analysis about radiation defense rule and substantiation advised international organization for the low way of patient's exposed dose in panoramic radiography of dental clinic and we judge need the additional study about radiation defense organization for protect the systematize protocol's finance and around internal organs for minimize until accepted by many people that is technological, economical and social fact by using panoramic measurement.

• Journal of the Korean Society of Radiology
• /
• v.9 no.7
• /
• pp.433-438
• /
• 2015

To evaluate the radiation exposure level based on radiation workers' locations in dental radiography, the radiation dose rate in the radiographic room, lead glass, and operation system was measured. To that end, various devices were used, such as a Standard(Max-GLS, Shinhung), a panorama (PCH-2500, Vatech), a cephalometric radiography (PCH-2500), and a cone beam CT (PHT-30LFO, Vatech), as well as a PM1405 equipment as a radiation meter. Radiography conditions were set the same as the factors used in the clinical setting. As the result, the cone beam CT turned out the highest with 98 uSv and the standard showed the lowest level with 0.4 uSv/h. The panorama was measured to be higher than the Cephalo due to its different focus mode. On the lead glass surface and in the operation stand, the oral radiography device, panoramic, and Cephalo all were measured below the recording level. However, the cone beam CT was measured to have the leakage dose. Thus, radiation involved workers should be equipped with appropriate protection tools and reduce radiography time as much as possible. In addition, the structure of the radiation chamber should be also designed efficiently. Dental radiography has continued to grow in recent years, so it is necessary take appropriate protection measures for patients and radiation workers.

• Journal of the Korean Society of Radiology
• /
• v.9 no.1
• /
• pp.17-21
• /
• 2015

Recently, As people's interest in the health of teeth is increased in the medical field changed into aging society, the number of times for the radiological diagnosis is increased. It can be said that the radiation exposure dose of Korean population is increased. It is also growing concern about radiation exposure. Therefore, the basic data for the dental panoramic X-ray system, its investigation and measuring the radiation dose is needed. In this study, we used ALOKA PDM-117 dosimeter and estimated a two-dimensional dose distribution of the dental panoramic X-ray system (VATEC Pax-400). Dose evaluation about the distribution is confirmed from the point of radiation exposure of a patient. Dose distribution of the dental panoramic X-ray system irradiated chin and the facial region to high dose as well as the parts of teeth. It was founded that the eye lens which are sensitive to radiation are exposed to unnecessary radiation, considering the effect of scattered radiation. The results of this study will be used more accurate dose assessment in a variety of object size and location of measuring dose.