• Radiation Oncology Journal
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• 제10권2호
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• pp.261-266
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• 1992

1987년 3월부터 1992년 3월까지 연세의료원 암쎈터 치료방사선과에서 방사선치료를 받은 Granulocytic sarcoma 환자를 대상으로 이들의 치료성적과 방사선 선량반응 관계를 알아보기 위해 후향성 분석을 하였다. 14예의 Granulocytic sarcoma 병변이 9예의 환자에서 발생하였고 급성, 만성 골수구성 백혈병 또는 무백헐병 상태 등과 같은 다양한 임상적 시기에 발생하였다. 병소부위는 내림 순으로 골, 임파절, 연부 조직과 피부이었다. 모든 14예의 병변은 외부 방사선(Co-60 또는 전자선)으로 치료 받았고 대다수의 병변이 2000 cGy 이상의 전 방사선 선량으로 국소 방사선 치료를 받았다. 연령 분포와 발생한 임상시기는 치료에 대한 반응과 관련이 없는 것으로 나타났다. 골에서 발생한 임상시기는 치료에 대한 반응과 관련이 없는 것으로 나타났다. 골에서 발생한 병변은 다른 부위에서 발생한 병변에 비해 치료에 대한 반응이 더 좋은 것 같았다. 2000 cGy이상의 방사선 선량을 받은 병변은 $100\%$ (l1/11)의 월등한 국소 제어율을 보였지만 2000 cGy이하의 방사선 선량을 받은 병변은 $33\%$ (1/3)의 감소된 국소 제어율을 보였다. 결론적으로 국소 방사선 치료는 Granulocytic sarcoma의 완화 또는 완치 목적의 치료에 있어 효과적이면 이때 2000 cGy이상의 방사선 선량이 필요한 것으로 생각된다.

• 구강회복응용과학지
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• 제31권3호
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• pp.169-177
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• 2015

목적: 한국인의 상악 전치부 순측골 두께와 치은 생체형(gingival biotype)의 분포 및 상관관계를 평가하는 것이다. 연구 재료 및 방법: 본 연구는 부산대학교치과병원에 내원한 57명의 환자, 335개의 치아를 대상으로 시행되었다. Cone Beam Computed Tomography (CBCT)를 이용하여 백악법랑경계로부터 4 mm, 6 mm, 8 mm 지점의 순측골 두께를 측정하였고, 치은 생체형은 치주탐침자를 이용하여 평가하였다. 결과: 대부분의 대상치아에서 1 mm 이하의 얇은 순측골(4 mm 지점 87%, 6 mm 지점 88%, 8 mm 지점 90%)이 우세하게 관찰되었고, 전체 대상자의 21%에서 얇은 치은 생체형이 확인되었다. 치은 생체형과 순측골 두께 사이의 유의한 상관관계는 존재하지 않았다. 결론: 성공적인 전치부 심미 임플란트 치료를 위해서는 치은 생체형 검사 같은 임상적 검사 이외에 순측골 평가를 위한 추가적 CBCT 등의 방사선 검사가 필수적이다.

• Journal of Periodontal and Implant Science
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• 제41권1호
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• pp.23-29
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• 2011

Purpose: To investigate the healing pattern of the mucous membrane after tooth extraction necessitated by periodontal disease in the maxillary sinus. Methods: One hundred and three patients with 119 maxillary sinuses were investigated. Before implant placement, cone-beam computed tomography (CT) scanning was performed. The causes of extraction, the time elapsed since extraction, smoking, periodontal disease in adjacent teeth, and gender were recorded. In addition, the thickness of the mucous membrane of the maxillary sinus and the height of residual alveolar bone at the extracted area were calculated from CT images. Results: The thickness of the mucous membrane in the periodontal disease group ($3.05{\pm}2.71\;mm$) was greater than that of the pulp disease group ($1.92{\pm}1.78\;mm$) and the tooth fracture group ($1.35{\pm}0.55\;mm$; P<0.05). The causes of extraction, the time elapsed since extraction, and gender had relationships with a thickening of the mucous membrane of the maxillary sinus (P<0.05). In contrast, the height of the residual alveolar bone at the extracted area, periodontal disease in adjacent teeth, and smoking did not show any relation to the thickening of the mucous membrane of the maxillary sinus. Conclusions: The present study revealed distinct differences in healing patterns according to the causes of extraction in the maxillary sinus, especially periodontal disease, which resulted in more severe thickening of the mucous membrane.

• 대한치과교정학회지
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• 제50권5호
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• pp.346-355
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• 2020

The treatment of skeletal Class III malocclusion in adolescents is challenging. Maxillary protraction, particularly that using bone anchorage, has been proven to be an effective method for the stimulation of maxillary growth. However, the conventional procedure, which involves the surgical implantation of mini-plates, is traumatic and associated with a high risk. Three-dimensional (3D) digital technology offers the possibility of individualized treatment. Customized mini-plates can be designed according to the shape of the maxillary surface and the positions of the roots on cone-beam computed tomography scans; this reduces both the surgical risk and patient trauma. Here we report a case involving a 12-year-old adolescent girl with skeletal Class III malocclusion and midface deficiency that was treated in two phases. In phase 1, rapid maxillary expansion and protraction were performed using 3D-printed mini-plates for anchorage. The mini-plates exhibited better adaptation to the bone contour, and titanium screw implantation was safer because of the customized design. The orthopedic force applied to each mini-plate was approximately 400-500 g, and the plates remained stable during the maxillary protraction process, which exhibited efficacious orthopedic effects and significantly improved the facial profile and esthetics. In phase 2, fixed appliances were used for alignment and leveling of the maxillary and mandibular dentitions. The complete two-phase treatment lasted for 24 months. After 48 months of retention, the treatment outcomes remained stable.

• 한국의학물리학회지:의학물리
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• 제7권2호
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• pp.47-55
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• 1996

백혈병 환자에서 골수이식을 하기전 전신방사선조사를 시행할 때 우선적으로 해결되어야 할 과제는 총선량의 결정과 머리, 목, 폐, 복부, 골반과 다리등 모든 부위에 동일한 선량을 조사하는 것이다. 본 연구에서는 머리, 목, 폐등 밀도와 두께에 따른 선량보정을 Al으로 만든 조직보상체를 이용하는 미네소타대학 방법(방법 1) 과 소아들이 장시간 동안 편안한 자세로 움직이지 않고 치료받을수 있도록 본원에서 개발한 고정치료틀에 조직등가불질로 머리, 목, 폐등을 보정한 방법(방법 2)의 선량분포를 비교검토하였다. 또한 슬로안-케트링 병원에서 시행하고 있는 똑바로 앉아 치료하는 경우(방법 3) 선량분포와 폐 차폐에 따른 차폐체 제작 및 여러 가지 문제들을 고려하였다. 방법 1에서는 95.6％ 에서 100％의 선량 분포를 보였으며, 방법 2에서는 95.4％에서 100％의 선량분포를 보였다. 또한 방법 2에서 중심 부위와 표면 부위의 선량분포는 머리 부위에서 103.4％, 목 부위에서 101.5％, 배꼽 부위에서 102.3％를 나타내었다.

• Radiation Oncology Journal
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• 제5권2호
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• pp.75-82
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• 1987

원자력병원 싸이클로트론으로 발생되는 고에너지 속중성자선의 생물학적효과에 대한 연구의 일환으로 RBE를 측정하였다. 대상은 Walker 256 carcinosacoma 및 정상조직으로 마우스 위장관 및 골수를 이용하였고 단일 및 분할조사에 대한 반응을 관찰하였다. 마우스 공장소낭선세포의 단일전신조사에 의한 RBE는 2.8이었다. 단일조사시 이식암 Walker 250의 TCD 50에 대한 RBE, 마우스 골수 및 위장관의 RBE는 각각 1.9, 1.9, 1.5이었다. 분할조사시 Walker 256의 RBE는 분할횟수의 증가에 따라 감소하였고 1회 분할조사량의 증가에 따라 증가하였다.

• Journal of Periodontal and Implant Science
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• 제50권3호
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• pp.146-158
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• 2020

Purpose: The aim of this study was to investigate and identify the main causes of periodontal tissue change associated with labial gingival recession by examining the anterior region of patients who underwent orthodontic treatment. Methods: In total, 45 patients who had undergone orthodontic treatment from January 2010 to December 2015 were included. Before and after the orthodontic treatment, sectioned images from 3-dimensional digital model scanning and cone-beam computed tomography images in the same region were superimposed to measure periodontal parameters. The initial labial gingival thickness (IGT) and the initial labial alveolar bone thickness (IBT) were measured at 4 mm below the cementoenamel junction (CEJ), and the change of the labial gingival margin was defined as the change of the distance from the CEJ to the gingival margin. Additionally, the jaw, tooth position, tooth inclination, tooth rotation, and history of orthognathic surgery were investigated to determine the various factors that could have affected anterior periodontal tissue changes. Results: The mean IGT and IBT were 0.77±0.29 mm and 0.77±0.32 mm, respectively. The mean gingival recession was 0.14±0.57 mm. Tooth inclination had a significant association with gingival recession, and as tooth inclination increased labially, gingival recession increased by approximately 0.2 mm per 1°. Conclusions: In conclusion, the IGT, IBT, tooth position, tooth rotation, and history of orthognathic surgery did not affect labial gingival recession. However, tooth inclination showed a significant association with labial gingival recession of the anterior teeth after orthodontic treatment.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2012년도 춘계학술발표대회
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• pp.55.2-55.2
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• 2012

Intensive theoretical and experimental studies have been carried out at Korean Institute of Science and Technology (KIST) on controlling the bio absorbing rate of the Mg alloys with high mechanical strength through tailoring of electrochemical potential. Key technology for retarding the corrosion of the Mg alloys is to equalize the corrosion potentials of the constituent phases in the alloys, which prevented the formation of Galvanic circuit between the constituent phases resulting in remarkable reduction of corrosion rate. By thermodynamic consideration, the possible phases of a given alloy system were identified and their work functions, which are related to their corrosion potentials, were calculated by the first principle calculation. The designed alloys, of which the constituent phases have similar work function, were fabricated by clean melting and extrusion system. The newly developed Mg alloys named as KISTUI-MG showed much lower corrosion rate as well as higher strength than previously developed Mg alloys. Biocompatibility and feasibility of the Mg alloys as orthopedic implant materials were evaluated by in vitro cell viability test, in vitro degradation test of mechanical strength during bio-corrosion, in vivo implantation and continuous observation of the implant during in vivo absorbing procedures. Moreover, the cells attached on the Mg alloys was observed using cryo-FIB (focused ion beam) system without the distortion of cell morphology and its organ through the removal of drying steps essential for the preparation of normal SEM/TEM samples. Our Mg alloys showed excellent biocompatibility satisfying the regulations required for biomedical application without evident hydrogen evolution when it implanted into the muscle, inter spine disk, as well as condyle bone of rat and well contact interface with bone tissue when it was implanted into rat condyle.

• 대한치과교정학회지
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• 제50권3호
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• pp.216-226
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• 2020

Root resorption can be caused by several factors, including contact with the cortical bone. Here we report a case involving a 21-year-old female with Angle Class II, division 1 malocclusion who exhibited significant root resorption in the maxillary right central incisor after orthodontic treatment. The patient presented with significant left-sided deviation of the maxillary incisors due to lingual dislocation of the left lateral incisor and a Class II molar relationship. Cephalometric analysis demonstrated a Class I skeletal relationship (A point-nasion-B point, 2.5°) and proclined maxillary anterior teeth (upper incisor to sella-nasion plane angle, 113.4°). The primary treatment objectives were the achievement of stable occlusion with midline agreement between the maxillary and mandibular dentitions and appropriate maxillary anterior tooth axes and molar relationship. A panoramic radiograph obtained after active treatment showed significant root resorption in the maxillary right central incisor; therefore, we performed cone-beam computed tomography, which confirmed root resorption along the cortical bone around the incisive canal. The findings from this case, where different degrees of root resorption were observed despite comparable degrees of orthodontic movement in the bilateral maxillary central incisors, suggest that the incisive canal could be an inducing factor for root resorption. However, further investigation is necessary to confirm this assumption.

• 대한치과교정학회지
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• 제52권6호
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• pp.399-411
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• 2022

Objective: The objective of this randomized clinical trial was to study the skeletal and dental effects of low-level laser therapy (LLLT) along with a miniscrew-assisted expander (Hyrax) after six months of retention. Methods: After sequence generation, concealed allocation, and implementation, 24 female patients were randomly divided (1:1) into two-groups: bone-borne rapid palatal expansion (BBE) without LLLT (n = 12) and BBE with LLLT (n = 12). Eligibility criteria included female patients aged 10-13 years old with bilateral posterior crossbites. Intraoral and extraoral photographs, cone-beam computed tomography images, and digital study models were obtained before expansion and six months after retention. The 7 mm Hyrax appliance was anchored to four palatal mini-screws, which were activated twice daily for 15 days, then locked and kept in place as a retainer. LLLT was performed in the laser group during expansion and retention, according to the guidelines provided. Results: The records of 24 patients were analyzed. According to the post-retention measurements, both groups showed a significant increase in nasal and maxillary widths and total facial height. In the laser group, the Sella-Nasion-Point A and Point A-Nasion-Point B angles and the interpremolar apical distance were significantly increased. Conclusions: Within the limitations of this study, the results suggest that the parameters and protocol of LLLT do not clinically affect the efficiency of BBE in prepubertal and pubertal patients.