• The Journal of the Korean dental association
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• v.16 no.1 s.104
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• pp.37-42
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• 1978

A study on the impacted teeth of the anterior segment was carried out. The data for this study were compiled form 1739 outpatients of the Department of Orthodontics, College of Dentistry, Seoul National University. The following conclusions were obtained; 1. The frequency of the impacted teeth of the anterior segment was 2.8% and the frequency of male was 4.0%, that of female was 2.1%., respectively. 2. The order of occurrence of the impacted teeth in the anterior segment was maxillary canine mesiodens, maxillary central incisor, maxillary lateral incisor, mandibular canine. 3. The etiologic factors of the impaction were the space deficiency for eruption, cleft palate, the prolonged retention of deciduous teeth, dentigerous cyst. 4. The favorable results of treatment and prognosis were obtained from the impacted teeth of the normal shape after surgical exposure and adhered the plastic attachment and inducted them into the dental arch.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.41 no.3
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• pp.149-155
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• 2015

Surgical approaches to the condylar fracture include intraoral, preauricular, submandibular, and retromandibular approaches. Each approach has its own advantages and disadvantages. When a patient needs esthetic results and an intraoral approach is not feasible, the transmasseteric antero-parotid facelift approach is considered. This approach permits direct exposure and allow the surgeon to fixate the fractured unit tangentially. Tangential fixation is critical to osteosynthesis. Disadvantages of the transmasseteric antero-parotid facelift approach include damage to the facial nerve and a longer operation time. However, after the initial learning curve, facial nerve damage can be avoided and operation time may decrease. We report three cases of subcondylar fractures that were treated with a transmasseteric antero-parotid facelift approach. Among these, two cases had trivial complications that were easily overcome. Instead of dissecting through the parotid gland parenchyma, the transmasseteric antero-parotid facelift approach uses transmasseteric dissection and reduces facial nerve damage more than the retromandibular transparotid approach. The esthetic result is superior to that of other approaches.

• Journal of Korean Neurosurgical Society
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• v.29 no.12
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• pp.1677-1681
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• 2000

Microsurgical transthoracic extrapleural approach for thoracic discectomy in three cases were modified and simplified in order to achieve better exposure of ventral extradural space than posterolateral extrapleural(lateral extracavitary) approach and less pulmonary complications than transthoracic transpleural approach. These approaches were optimized by microscope and video-assistance. Surgery was followed by clinical improvement in all patients. The results of treatment seem to support the use of these modified techniques as adequate surgical treatment of thoracic disc herniations without any complications.

• The korean journal of orthodontics
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• v.21 no.3
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• pp.711-722
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• 1991

The first patient of this case was 13 year and 8 month old girl who had the Angle's class I malocclusion with uneruption of upper left central incisor and left canine. The second patient was 12 year old boy who had the Angle's class I malocclusion with uneruption of right central incisor. After surgical exposure of impacted teeth of those patients and bonding of attachment on exposed crown, those teeth were orthodontically pulled with removable appliances. The results were obtained as follow. 1. The functionally proper occlusion was established by guidance of the impacted teeth into the normal position in the arch. 2. Establishment of esthetic and balanced arch form was achieved. 3. The possibility of restorative prosthetic treatment induced by extraction of impacted teeth was eliminated. 4. The psychologic relief of pubertal patient who was very sensitive to facial esthetics was gained.

• Journal of Korean Foot and Ankle Society
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• v.17 no.4
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• pp.257-263
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• 2013

Open reduction and internal fixation is currently considered as a gold standard of treatment in most of the intra-articular calcaneal fractures. Among various different approaches, extensile lateral approach is the most popular since it provides good exposure to the subtalar joint. However, wide skin incision followed by extensive soft tissue dissection leading to increased risk of wound breakdown is the most serious drawback. Sinus tarsi approach, a minimal invasive technique to approach the subtalar joint and reduce the intra-articular calcaneal fractures, provides good clinical outcome and less wound complications compared to the extensile lateral approach. This article introduces the surgical technique and review of the literature regarding the sinus tarsi approach.

• Journal of Chest Surgery
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• v.29 no.8
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• pp.861-866
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• 1996

Surgical angioplasty of isolated stenosis of the left main coronary artery(LMCA) restores a more physiologic flow to the myocardium, allows percutdneous transluminal coronary angioplasty (PTCA) of distal coronary stenoses at a later stage, and is a less time consuming and convenient procedure than the conventional coronary artery bypass grafting(CABG) . Between Jul. 1994 and Dec. 1995, 7 surgical angioplasty had been performed. LMCA stenoses involved ostium in 2 patients, middle third in 3, and dis- tal third in 2. In 2 patients, the origin of left anterior descending coronary artery was involved in conjunction with LMCA. T e additional coronary artery stenoses were found in 2 cases. One patient was emergently operated after coronary angiography following his cardiac arrest. LMCA was approached anteriorly in all patients. The pulmonary artery was transected in 3 patients for a better exposure. The onlay patch consisted or autologous or bovine pericardium. There was no postoperative myocardial infarction or mortality. Left ventricular functions were well preserved in all patients. Postoperative coronary angiography revealed widely patent LMCA in 5 cases, and mild narrowing of distal anastomotic sites in 2 cases. Provided that well defined indications are followed correctly, surgical angioplasty can be a safe alternative to conventional CABG.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.5
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• pp.497-503
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• 2014

Minimally invasive intramedullary nail insertion or plate osteosynthesis has shown good results for the treatment of long bone fractures. However, directly seeing the fracture site is impossible; surgeons can only confirm bone fragments through a fluoroscopic imaging system. The narrow field of view of the equipment causes malalignment of the fracture reduction, and radiation exposure to medical staff is inevitable. This paper suggests two methods to solve these problems: surgical navigation using 3D models reconstructed from computed tomography (CT) images to show the real positions of bone fragments and estimating the rotational angle of proximal bone fragments from 2D fluoroscopic images. The suggested methods were implemented using open-source code or software and evaluated using a model bone. The registration error was about 2 mm with surgical navigation, and the rotation estimation software could discern differences of $2.5^{\circ}$ within a range of $15^{\circ}$ through a comparison with the image of a normal bone.

• Journal of the Korean Society of Radiology
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• v.16 no.7
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• pp.843-849
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• 2022

In this study, the probability of secondary carcinogenesis was analyzed by measuring the exposure dose of surrounding normal organs during radiosurgery using a gamma knife. A pediatric phantom (Model 706-G, CIRS, USA) composed of human tissue-equivalent material was set to four tumor volumes of 0.25 cm³, 0.51 cm³, 1.01 cm³, and 2.03 cm³, and the average dose was 18.4 ± 3.4 Gy. After installing the Rando phantom on the table of the gamma knife surgical equipment, the OSLD nanoDot dosimeters were placed in the right eye, left eye, thyroid, thymus gland, right lung, and left lung to measure each exposure dose. The probability of cancer occurrence due to radiation exposure of surrounding normal organs during gamma knife radiosurgery for acoustic schwannoma disease was 4.08 cancers per 100,000 at a tumor volume of 2.03 cm³. This study is expected to be used as useful data in relation to stochastic effects in the future by studying the risk of secondary radiation exposure that can occur during stereotactic radiosurgery.

• Journal of the Korean Society of Radiology
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• v.17 no.2
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• pp.243-248
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• 2023

This study aims to analyze the secondary carcinogenesis rate caused by exposure of organs at risk of damage using a glass dosimeter during radiosurgery in vestibular schwannoma disease. Using a pediatric phantom of human tissue equivalent material, the volume of the tumor was set to a total of three volumes: 0.506 cm³, 1.008 cm³, and 2.032 cm³, and a radiosurgery plan was established with an average dose of 18.4 ± 3.4 Gy. After mounting the human body phantom on the table of surgical equipment, glass dosimeters were placed on the right eye, left eye, thyroid gland, thymus, right lung, and left lung to measure the exposure dose, respectively. In this study, the incidence of secondary cancer due to exposure to damaged organs during gamma knife radiosurgery in vestibular schwannoma disease with the largest tumor volume of 2.032 cm³ was measured with a glass dosimeter. This study studies the risk of secondary radiation exposure dose that can occur during stereotactic radiosurgery, and it is considered that it will be used as basic data in the field of radiation damage related to the stochastic effect of radiation in the future.

• Journal of Yeungnam Medical Science
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• v.13 no.1
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• pp.22-31
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• 1996

It is difficult to get a satisfactory result for the correction of malunited fracture of zygoma. Triple osteotomy and reposition of malunited zygoma is accepted as the better surgical method than camouflage surgery by means of onlays, if the orbital floor is to be reconstructed. The surgical approach can be divided into bicoronal, periorbital, intraoral and old scar. In 7 patients with malunited fracture of zygoma, the authors used a limited approach through extension of periorbital incision and intraoral incision instead of wide exposure including bicoronal incision. And we performed triple osteotomy and advancement of zygoma complex. The patients were followed for 4.5 months with acceptable result, and this approach was an effective method for the relatively simple tripod type-malunited fracture of zygoma. The authors obtained following conclusions: 1. Preoperative evaluation through thorough measurement of X-rays, investigation of photographs and detail communication with the patients was an important process. 2. Through lateral extension of subciliary incision, lateral eyebrow and intraoral incision, we could obtain adequate exposure for triple osteotomy and advancement of zygoma. 3. The zygoma should be reduced and fixed in an overcorrected superior and medial direction. 4. Return of zygoma to its anatomical position was possible only when it is completely freed from the surrounding soft tissue including masseter. 5. We could not find any different results between autogenous calvareal bone graft and $Medpor^{(R)}$ insertion on the floor of orbit.