• 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.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08b
• /
• pp.1239-1241
• /
• 2007

In this paper, we present a tiled display system for tangible meeting. We built our system as a distributed system and use GPU based warping and image blending technique for real-time processing. For efficiency, we update specific area only, where the remote user exist, in real-time and blended it with static panoramic image of remote site.

• Imaging Science in Dentistry
• /
• v.44 no.2
• /
• pp.103-113
• /
• 2014

Purpose: In this study, we aimed to develop dental charts for Turkish children and young adults of both genders within the age group of 4.5-22.5 years according to tooth mineralization and eruption in a format similar to that proposed by AlQahtani et al. Materials and Methods: In total, 753 digital panoramic radiographs from 350 males and 403 females were assessed. The permanent teeth were evaluated according to the classification system described by Demirjian et al. The eruption stage was assessed with Bengston's system, which was modified by AlQahtani et al at four points. Results: Teeth generally developed earlier in females than in males. This was particularly notable in the age group of 5-14 years. However, this difference was usually visible in only one stage, not in all teeth. It has been determined that the mixed dentition period ended with the shedding of the second deciduous molars in both genders. Conclusion: The dental charts presented here included information that could be beneficial to dental clinicians in making appropriate diagnosis and planning orthodontic and surgical procedures. These charts also provided datasets for preliminary dental age estimation in Turkish children and young adults.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.33 no.4 s.111
• /
• pp.11-21
• /
• 2005

The purpose of this study was to analyze and evaluate landscape characteristics by classification of landscapes in Chuncheon. A system was developed to convert images taken with a fish-eye lens to panoramic pictures. Landscape characteristics were analyzed by appearance rate and area distribution rate of landscape elements on panorama picture. Landscape characteristics were analyzed according to the number of times landscape elements appeared and the amount of area that each element occupied in the panoramic picture. Each panoramic picture was classified into five types based on these landscape element factors. Landscape evaluation was carried out using dynamic images converted from picture by fish-eye lens. The results of this study can be summarized as follows. The urban landscape can be characterized by four essential factors: interconnectedness, nature, urban centrality and landscape scale. Five types of landscapes were determined: detached residential building landscape (type 1), street landscape with various elements (type 2), street landscape in the center of a city (type 3), landscape of housing complex (type 4), and landscape of green space (type 5). Type 5 had the highest degree of landscape satisfaction and the landscape satisfaction increased with the number of appearances of natural elements. The amount of peen space had a high relation with a landscape satisfaction.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.40 no.6
• /
• pp.141-148
• /
• 2003

This paper proposes a new algorithm that generates the smooth and realistic transition views from one viewpoint to another on the multi-panorama based navigation system. The proposed algorithm is composed of two steps. One is prewarping that aligns the viewing directions of two panoramic images, and the other is the bidirectional disparity morphing(BDM) that generates the intermediate scene from the aligned panoramic images. For prewarping, we compute the phase correlation between two images in order to obtain the information, such as translation, rotation, and scaling. Then we align the viewing directions of two original images using these information. Afterprewarping, we compute the block based disparity vector(DV) and smooth them using two occluding patterns. As we apply these DVs to the BDM, we can generate the elaborate intermediate scene. We make an experiment on the proposed algorithm with some real panoramic images and obtain good quality intermediate scenes.

• Imaging Science in Dentistry
• /
• v.48 no.3
• /
• pp.201-212
• /
• 2018

Purpose: The aim of this study was to compare cone-beam computed tomography (CBCT) and digital panoramic radiography (DPR) for the detection of pulp stones. Materials and Methods: DPR and CBCT images of 202 patients were randomly selected from the database of our department. All teeth were evaluated in sagittal, axial, and coronal sections in CBCT images. The systemic condition of patients, the presence of pulp stones, the location of the tooth, the group of teeth, and the presence and depth of caries and restorations were recorded. The presence of pulp stones in molar teeth was compared between DPR and CBCT images. Results: Pulp stones were identified in 105 (52.0%) of the 202 subjects and in 434 (7.7%) of the 5,656 teeth examined. The prevalence of pulp stones was similar between the sexes and across various tooth locations and groups of teeth (P>.05). A positive correlation was observed between age and the number of pulp stones(${\rho}=0.277$, P<.01). Pulp stones were found significantly more often in restored or carious teeth (P<.001). CBCT and DPR showed a significant difference in the detection of pulp stones(P<.001), which were seen more often on DPR than on CBCT. Conclusion: DPR, as a 2D imaging system, has inherent limitations leading to the misinterpretation of pulp stones. Restored and carious teeth should be carefully examined for the presence of pulp stones. CBCT imaging is recommended for a definitive assessment in cases where there is a suspicion of a pulp stone on DPR.

• 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 Korea Multimedia Society
• /
• v.15 no.5
• /
• pp.569-576
• /
• 2012

This paper presents an x-ray medical image panorama system which can overcome the smallness of the images that exist on a source computer during remote medical processing. In the system, after the standard medical image format DICOM is converted to the PC standard image format, a MSR algorithm is used to enhance X-ray images of low quality. Then SURF and Multi-band blending are applied to generate a panoramic image. Also, this paper evaluates the proposed SURF based system through the average gray value error and image quality criterion with X-ray image data by comparing with a SIFT based system. The results show that the proposed system is superior to SIFT based system in image quality.

• Proceedings of the KSRS Conference
• /
• 2008.10a
• /
• pp.137-140
• /
• 2008

Recently many areas require wide field of view images. Such as surveillance, virtual reality, navigation and 3D scene reconstruction. Conventional camera systems have a limited filed of view and provide partial information about the scene. however, omni directional vision system can overcome these disadvantages. Acquiring 360 degree panorama images requires expensive omni camera lens. In this study, 360 degree panorama image was tested using a low cost optical reflector which captures 360 degree panoramic views with single shot. This 360 degree panorama image system can be used with detailed positional information from GPS/INS. Through this study result, we show 360 degree panorama image is very effective tool for mobile monitoring system.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.48 no.3
• /
• pp.255-268
• /
• 2021

The aim of this study was to investigate the relationships between the stages of calcification of various teeth and skeletal maturity stages among Korean subjects. The samples were derived from hand-wrist, panoramic radiographs, and lateral cephalograms of 743 subjects (359 males and 384 females) with ages ranging from 6 to 14 years. Calcification of seven permanent mandibular teeth on the left side were rated according to the system of Demirjian. To evaluate the stage of skeletal maturation, hand-wrist radiographs were analyzed by skeletal maturity indicators (SMI) system of Fishman and lateral cephalograms by cervical vertebral maturation (CVM) method of Baccetti. Statistically significant relationships were found between dental calcification and skeletal maturity stages according to Spearman rank-order correlation coefficients (r = 0.40-0.84, p < 0.001). The second molar showed the highest correlation and central incisor showed the lowest correlation for female and male subjects. For both sexes, canine stage G and second molar stage F were related to SMI 6 and CS 3. Because of the high correlation coefficients, this study suggests that tooth calcification stages from panoramic radiographs might be clinically useful as a maturity indicator of the pubertal growth period in Korean patients.