• Journal of Dental Rehabilitation and Applied Science
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• v.37 no.4
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• pp.268-273
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• 2021

Paramolar tubercle is a rare developmental dental anomaly defined as an additional cusp occurring on the buccal or lingual surfaces of the molar. Permanent molar fused with paramolar tubercles can be a cause of difficulty in root canal treatment. Therefore, proper understanding of these variations is important in order to ensure successful endodontic treatment. Cone beam computed tomography (CBCT) can be helpful to understand anatomy of complicated cases. This case report describes nonsurgical endodontic treatment of maxillary second premolar fused with paramolar tubercle.

• Journal of the Korean Society of Radiology
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• v.81 no.1
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• pp.81-100
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• 2020

Magnetic resonance neurography (MRN) has been increasingly used in recent years for the assessment of peripheral neuropathies. Fat suppression T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) have typically been used to provide high contrast MRN. Isotropic 3-dimensional (3D) sequences with fast spin echo, post-processing imaging techniques, and fast imaging methods, among others, allow good visualization of peripheral nerves that have a small diameter, complex anatomy, and oblique course within a reasonable scan time. However, there are still several issues when performing high contrast and high resolution MRN including standard sequence; fat saturation techniques; balance between resolution, field of view, and slice thickness; post-processing techniques; 2D vs. 3D image acquisition; different T2 contrasts between proximal and distal nerves; high T2 signal intensity of adjacent veins or joint fluid; geometric distortion; and appropriate p-values on DWI. The proper understanding of these issues will help novice radiologists evaluate peripheral neuropathies using MRN.

• Progress in Medical Physics
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• v.14 no.1
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• pp.34-42
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• 2003

In medical imaging, three-dimensional (3D) display using Virtual Reality Modeling Language (VRML) as a portable file format can give intuitive information more efficiently on the World Wide Web (WWW). The web-based 3D visualization of functional images combined with anatomical images has not studied much in systematic ways. The goal of this study was to achieve a simultaneous observation of 3D anatomic and functional models with planar images on the WWW, providing their locational information in 3D space with a measuring implement using VRML. MRI and ictal-interictal SPECT images were obtained from one epileptic patient. Subtraction ictal SPECT co-registered to MRI (SISCOM) was performed to improve identification of a seizure focus. SISCOM image volumes were held by thresholds above one standard deviation (1-SD) and two standard deviations (2-SD). SISCOM foci and boundaries of gray matter, white matter, and cerebrospinal fluid (CSF) in the MRI volume were segmented and rendered to VRML polygonal surfaces by marching cube algorithm. Line profiles of x and y-axis that represent real lengths on an image were acquired and their maximum lengths were the same as 211.67 mm. The real size vs. the rendered VRML surface size was approximately the ratio of 1 to 605.9. A VRML measuring tool was made and merged with previous VRML surfaces. User interface tools were embedded with Java Script routines to display MRI planar images as cross sections of 3D surface models and to set transparencies of 3D surface models. When transparencies of 3D surface models were properly controlled, a fused display of the brain geometry with 3D distributions of focal activated regions provided intuitively spatial correlations among three 3D surface models. The epileptic seizure focus was in the right temporal lobe of the brain. The real position of the seizure focus could be verified by the VRML measuring tool and the anatomy corresponding to the seizure focus could be confirmed by MRI planar images crossing 3D surface models. The VRML application developed in this study may have several advantages. Firstly, 3D fused display and control of anatomic and functional image were achieved on the m. Secondly, the vector analysis of a 3D surface model was defined by the VRML measuring tool based on the real size. Finally, the anatomy corresponding to the seizure focus was intuitively detected by correlations with MRI images. Our web based visualization of 3-D fusion image and its localization will be a help to online research and education in diagnostic radiology, therapeutic radiology, and surgery applications.

• Korean Journal of Plant Taxonomy
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• v.39 no.2
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• pp.63-73
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• 2009

$Iso{\ddot{e}}tes$ L. ($Iso{\ddot{e}}taceae$) is difficult to identify among the infrageneric taxa because of morphological simplicity. Since two species (I. japonica and I. coreana) had been reported, I. jejuensis and I. hallasanensis were described as two new species from Jeju Island, South Korea. The habitats of all species were confirmed by current studies except for I. japonica. We compared the morphological and anatomical characters of seven species, three domestic species and four species in adjacent regions (I. taiwanensis, I. sinensis, I. japonica, and I. asiatica). I. asiatica differs from other species in the lobe number of corm, spreading sporophylls, lack of stomata and degree of velum development. All of the seven species were identified by the characteristics of their mega- and microspores. Especially, it was possible to identify the four species in South Korea by the types of ornamentation on their megaspores. Each species has a specific type of megaspore ornamentation: I. coreana - cristate, I. jejuensis - rugulate, I. hallasanensis - echinate, and I. japonica - reticulate. We also discussed the phylogeny of the genus in East Asia in relation to recent studies based on the second intron of LEAFY sequence and amplified fragment length polymorphism (AFLP) analysis. We suggest strategies for the conservation of the endangered $Iso{\ddot{e}}tes$ species in South Korea.

• Korean Journal of Ichthyology
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• v.21 no.2
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• pp.81-86
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• 2009

The spermiogenesis and mature spermatozoa of Pseudobagrus fulvidraco were described by means of scanning and transmission electron microscopy. Spermiogenesis is characterized by lateral development of the flagellum, nuclear rotation, deep nuclear fossa formation and compaction into thick granules. The spermatozoa exhibit a round head containing a nucleus that lacks an acrosome, and having a midpiece and a flagellum. The midpiece is small and has a short cytoplasm including several mitochondria separated from the tail by the cytoplasmic canal. The flagellum contains the 9+2 classical axoneme structure and has two axonemal fins. The presence of axonemal fins in the flagellum is a common character in Bagridae. The interrelationships among the Bagridae as well as other teleosts are herein discussed.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.2
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• pp.243-255
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• 2017

Cardiopulmonary resuscitation (CPR) is an emergency treatment that stimulates blood circulation and breathing when the function of the heart stops or stops breathing. CPR can be divided by basic life support (BLS) and advanced life support (ALS). BLS involves the use of chest compression to force the blood flow to the main organs, rescue breathing to improve the breathing to the respiratory failure patient and the use automated external defibrillator (AED). The categories of advanced life support include advanced cardiovascular life support (ACLS) for adult and pediatric advanced life support (PALS) for children. In the treatment of dental care for children, which is extremely difficult to deal with, and for a variety of reasons, the use of sedation is considered to treat the children who are unlikely to cooperate with dentistry. This is why there is an increasing possibility of an emergency situation involving cardiac arrest. PALS includes the BLS, and it presents a systematic algorithm to treat respiratory failure, shock and cardiogenic cardiac arrest. In order to manage emergency situations in the pediatric dental clinic, respiratory support is most important. Therefore, mastering professional PALS, which includes respiratory care and core cases, particularly upper airway obstruction and respiratory depression caused by a respiratory control problem, would be highly desirable for a physician who treats pediatric dental patients. Regular training and renewal training every two years is necessary to be able to immediately implement professional skills in emergency situations.

• Journal of Oral Medicine and Pain
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• v.26 no.3
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• pp.277-290
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• 2001

영상촬영술은 개방형 외과적 관절수술이나 관절경 검사법을 할 수 없는 상태에서 관절의 상태에 대한 시각적 정보를 확보할 수 있는 유일한 방법이다. 이것의 주된 목적은 진단과 치료계획과정을 도와주는 정보를 제공하는데 있다. 그중 방사선 촬영술은 턱관절의 구조적 질병을 진단하는데 기본적인 수단으로서 오래동안 사용되어 왔 다. 그러나 어떠한 방사선 소견이 개별 관절질환의 특징적 소견인지는 찾아내기가 어려운 실정이다. 그러나 통상적 턱관절 방사선 촬영술로서도 구조적 골변화를 찾아낼 수 있으며 특히 시상 단층촬영술은 턱관절에서 가장 유익한 정보를 보여준다고 한다. 또한 보고에 의하면 턱관절 장애는 다양한 해부학적 요인들과 관련이 있다고 한다. 따라서 본 연구에서는 통상적인 방사선 단층촬영술을 이용하여 턱관절 장애환자의 턱관절에서 나타나는 골변화를 찾아내고 이러한 골변화가 하악과두 수평각, 하악과두 형태, 과두위치 등과 같은 여러 요인들과 서로 관련이 있는 지 찾아보고저 하였다. 단국치대 구강내과 안면동통진료실에 내원한 256명의 환자 중, 턱관절장애를 편측으로만 호소하는 환자 73명을 대상으로 SCANORA를 이용하여 방사선 단층촬영을 시행하였다. 먼저 악하두정위 촬영을 통해 정중선에 대한 하악과두의 방향을 찾아내고 단층촬영 부위를 계산하였으며, 모든 촬영면은 4 mm 두께로 하고 턱관절 부위에만 국한되도록 조준하였다. 폐구 시 4개의 시상 촬영과 개구 시 한개의 시상 및 전두촬영상을 구한 후, 하악과두, 과두 형태 및 하악과두위치 등과 같은 요인들에 대한 골변화간의 관련성을 조사하고저 자료를 측정한 후 Contengency table analyses를 시행하였다. 본 연구의 결과에 따르면 결론적으로 하악과두의 형태, 하악과두의 수평각 및 하악과두의 위치 등은 턱관절의 골변화와 상호 관련이 있다는 가설을 확인할 수 있었다. 즉 하악과두상의 골변화는 과두가 후방위치되고 과두각이 25도 이상 크며, 특히 20대에서는 flat type, 40대에서는 angled type의 과두형태를 가지며 두 과두각의 차이가 9도에서 12도 정도로 큰 차이가 있는 남성환자에서 증가한다.

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.235-243
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• 2020

Lumbar Lordosis Angle (LLA) is an index that can be used to evaluate the curvature of the lumbar vertebrae. It can measure the structural stability of the lumbar spine and the stability of each segment of the vertebral column at the intervertebral disc angle (IDA). Especially, our data shows it is found to be a strong positive correlation between obesity and the angle of lordosis for lumbar vertebrae. Also, the reason for the large IDA in the case of obesity seems to be the result of the weakening of anatomical structure as well as the gravity effect. And, the obesity interferes with normal sagittal balance and fails to maintain a straight posture with minimal energy. Therefore, the obesity can be an important factor in causing back pain by changing the lumbar lordosis.

• Korean Journal of Animal Reproduction
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• v.23 no.1
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• pp.69-73
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• 1999

A calf with derodidymus was delivered from a 3-year old Korean-native cow with abortion last ime at Jangheong area in Chonnam Province. The anomaly with body weight of 35 kg was born t the normal time of parturition. During the parturition, however, the calf with twin head was onfirmed and the complete amputation between fore and hind limb was inevitably carried out or safety of the dam. The calf had normal skeleton and extremities but had two heads and cervical vertebrae divided from upper thoracic part. At necropsy, there were found totally 3 pairs of ore limbs including two pairs of hypoplastic ones hided in the thoracic limb and also found one air of sternum. One head had incomplete torsion or unilateral hypoplasia of mandible with artly hypoplastic skull. There were marked fusion and torsion from cervical to 3rd thoracic vertebra. No abnormality was found on all organs in the pleural and abdominal cavities except a rectal stricture formed at 5 cm away from the atresia ani.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.275-280
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• 2009

Radicular cyst is a true epithelium lined cyst formed when epithelium at the apex of a nonvital tooth is stimulated by inflammation. It is the most common type of cyst in the oral cavity, but its frequency is low in the primary dentition. Treatment of large-sized cyst aims at conservation of adjacent structure and allowance of proper eruption of the successive permanent teeth in the primary dentition. Considering these two aspects, marsupialization or enucleation following decompression is recommended as a treatment means for large-sized radicular cyst. In this case, 8-year old boy visited the pediatric dentistry department. Yonsei University Dental Hospital, with the chief complaint of pain on the lower right area. Clinical and radiographic examinations revealed periapical radiolucent lesion on #84, which had previous pulp treatment and restorated with the stainless steel crown. Dislocation of its successive tooth, #44, was also observed. #84 was extracted and sent for biopsy. Through histologic examination, it was diagnosed as radicular cyst. Following its extraction, removable space maintainer was delivered, which was also used as a decompressor. During periodic check-up for next 22 months, favorable healing of the lesion and eruption of the successive tooth were observed.