• 대한수학회보
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• 제49권5호
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• pp.1089-1099
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• 2012

We construct three kinds of complete embedded singly-periodic minimal surfaces in $\mathbb{H}^2{\times}\mathbb{R}$. The first one is a 1-parameter family of minimal surfaces which is asymptotic to a horizontal plane and a vertical plane; the second one is a 2-parameter family of minimal surfaces which has a fundamental piece of finite total curvature and is asymptotic to a finite number of vertical planes; the last one is a 2-parameter family of minimal surfaces which fill $\mathbb{H}^2{\times}\mathbb{R}$ by finite Scherk's towers.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제17권4호
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• pp.299-306
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• 2010

In this article we consider axes of a complete embedded minimal surface in $R^3$ of finite total curvature, and then prove that there is no planar ends at which the Gauss map have the minimum branching order if the minimal surface has a single axis.

• 대한수학회보
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• 제53권2호
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• pp.531-540
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• 2016

In this work, we introduce the complete Riemannian manifold $\mathbb{F}_3$ which is a three-dimensional real vector space endowed with a conformally flat metric that is a solution of the Einstein equation. We obtain a second order nonlinear ordinary differential equation that characterizes the helicoidal minimal surfaces in $\mathbb{F}_3$. We show that the helicoid is a complete minimal surface in $\mathbb{F}_3$. Moreover we obtain a local solution of this differential equation which is a two-parameter family of functions ${\lambda}_h,K_2$ explicitly given by an integral and defined on an open interval. Consequently, we show that the helicoidal motion applied on the curve defined from ${\lambda}_h,K_2$ gives a two-parameter family of helicoidal minimal surfaces in $\mathbb{F}_3$.

• 호남수학학술지
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• 제5권1호
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• pp.267-272
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• 1983

• 대한수학회보
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• 제38권4호
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• pp.753-761
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• 2001

We introduce the notion of Gauss map of pointwise 1-type on ruled surfaces in the Euclidean 3-space for which vector valued functions is neither trivial nor it extends or coincides with the usual notion of 1-type, in general. We characterize the minimal helicoid in terms of it and give a complete classification of the ruled surfaces with pointwise 1-type Gauss map.

• 대한치과보철학회지
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• 제57권4호
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• pp.350-355
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• 2019

성공적인 총의치를 위해서는 유지, 안정, 지지 세가지 요소가 필수적으로 요구된다. 또한 심한 치조제의 흡수나 수술에 의한 반흔으로 인해 하악 설측변연 형성이 어려운 총의치 제작시에는 무교두 치아배열, 연마면 인상, 무게 보강 내부금속 삽입, 의치 접착 크림의 사용 등의 다양한 고려사항이 필요하다. 본 환자의 경우 심한 치주염으로 심하게 골흡수가 된 무치악 치조제를 가졌고, 또한 설암으로 인한 설절제술로 인해 연조직의 문제를 가진 환자이다. 부가적인 유지와 안정을 얻기 위해 연마면 인상과 내부 보강 금속구조물의 삽입 그리고 최소 가압 인상 등의 방법을 적용하여 보다 나은 임상적 결과를 나타내었다. 또한 원하는 3차원적 형태를 정확하게 부여하고 제작시 복잡한 기공과정을 줄인 금속 구조물을 제작하기 위해 최소 가압 인상 채득과 Direct metal laser sintering이 사용되었다.

• Journal of Chest Surgery
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• 제2권2호
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• pp.167-167
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• 1969

Two groups of esophagus graft were done in canine esophagus in 34 adult mongrel dogs. For the first group segmental replacement graft was done with fresh autologous pericardium tube, and for the second, patch graft was done utilizing fresh autologous pericardium, fresh homologous pericardium,and dacron piece. All eight dogs in the first segmental replacement graft group died 2 to 5 days after operation with severe empyema caused by anastomosis disruption. Among 26 patch graft dogs 2 died during operation and 7 died 13 to 18 days after operation. For the 17 long-term patch grafted survivors esophagography and postoperative weight check were done. Postoperative stool was collected and examined for dacron patch excretion. One, two, three, and four months postoperative long-term survivors were sacrificed to obtain specimens in each group respectively and the following observations were made.I. Survival; Autologous pericardium patch group showed no mortality but in homologous pericardium and dacron patch group only two thirds were long-term survivors. II. Postoperative swallowing; There was no case which demonstrated postoperative dysphagia. About half of the cases showed postoperative weight increase and in only 3 cases weight decrease followed operation. III. Dacron patch was excreted in the stool 8 to 23 days after operation. Animals which excreted dacron patch up to 9 days after operation all died of empyema due to anastomosis disruption.IV. Postoperative esophagogram; All esophagograms in each group showed no leakage of barium, no passage disturbances and no remarkable stenotic signs.V. Morphological findings; [A] Macroscopical findings; In one month group specimens of each group dense adhesion with surrounding structures was noted and luminal surface was smooth with contraction of the patched area. In two month groups anastomosis sutures were still exposed but patched area showed lesser abnormality. In three to four months groups sutures were covered completely and patched area showed only very slight signs of contraction. [B] Microscopic findings; In one month group luminal surface of the replaced tissue [transplanted tissue] showed almost complete epithelial covering that is composed of several layers of squamous cells with no evidence of keratinization. Basement membrane was also well distinct throughout. Slight to minimal inflammatory cells comprising of large mononuclears, lymphocytes and plasma cells were observed in the subepithelial fibrous stroma consisted entirely of loose fibrous tissue containing many newly formed capillaries and fibroblastic proliferation. Scattered suture granulomas were found, few of which became acutely inflamed. In two months group repairing process progressed with lesser degree of inflammatory cell infiltration and young capillary proliferation. Fibrous tissue was more matured showing even focal collagenization.Suture granuloma persisted but with lesser reactive changes. Epithelial covering was that of a mature non-keratinizing stratified squamous epithelium. In three and four months groups the replaced area showed essentially similar histological findings. However, subepithelial stroma still consisted entirely of connective tissue without evidence of smooth muscle regeneration. In this group, inflammatory cell infiltration was minimal or negligible. Among these patch materials autologous pericardium group showed the most satisfactory repairing process.The above mentioned results may signify the feasibility of autogenous pericardium patch graft in clinical esophageal surgery.

• Journal of Chest Surgery
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• 제2권2호
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• pp.168-186
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• 1969

Two groups of esophagus graft were done in canine esophagus in 34 adult mongrel dogs. For the first group segmental replacement graft was done with fresh autologous pericardium tube, and for the second, patch graft was done utilizing fresh autologous pericardium, fresh homologous pericardium,and dacron piece. All eight dogs in the first segmental replacement graft group died 2 to 5 days after operation with severe empyema caused by anastomosis disruption. Among 26 patch graft dogs 2 died during operation and 7 died 13 to 18 days after operation. For the 17 long-term patch grafted survivors esophagography and postoperative weight check were done. Postoperative stool was collected and examined for dacron patch excretion. One, two, three, and four months postoperative long-term survivors were sacrificed to obtain specimens in each group respectively and the following observations were made. I. Survival; Autologous pericardium patch group showed no mortality but in homologous pericardium and dacron patch group only two thirds were long-term survivors. II. Postoperative swallowing; There was no case which demonstrated postoperative dysphagia. About half of the cases showed postoperative weight increase and in only 3 cases weight decrease followed operation. III. Dacron patch was excreted in the stool 8 to 23 days after operation. Animals which excreted dacron patch up to 9 days after operation all died of empyema due to anastomosis disruption. IV. Postoperative esophagogram; All esophagograms in each group showed no leakage of barium, no passage disturbances and no remarkable stenotic signs. V. Morphological findings; [A] Macroscopical findings; In one month group specimens of each group dense adhesion with surrounding structures was noted and luminal surface was smooth with contraction of the patched area. In two month groups anastomosis sutures were still exposed but patched area showed lesser abnormality. In three to four months groups sutures were covered completely and patched area showed only very slight signs of contraction. [B] Microscopic findings; In one month group luminal surface of the replaced tissue [transplanted tissue] showed almost complete epithelial covering that is composed of several layers of squamous cells with no evidence of keratinization. Basement membrane was also well distinct throughout. Slight to minimal inflammatory cells comprising of large mononuclears, lymphocytes and plasma cells were observed in the subepithelial fibrous stroma consisted entirely of loose fibrous tissue containing many newly formed capillaries and fibroblastic proliferation. Scattered suture granulomas were found, few of which became acutely inflamed. In two months group repairing process progressed with lesser degree of inflammatory cell infiltration and young capillary proliferation. Fibrous tissue was more matured showing even focal collagenization. Suture granuloma persisted but with lesser reactive changes. Epithelial covering was that of a mature non-keratinizing stratified squamous epithelium. In three and four months groups the replaced area showed essentially similar histological findings. However, subepithelial stroma still consisted entirely of connective tissue without evidence of smooth muscle regeneration. In this group, inflammatory cell infiltration was minimal or negligible. Among these patch materials autologous pericardium group showed the most satisfactory repairing process. The above mentioned results may signify the feasibility of autogenous pericardium patch graft in clinical esophageal surgery.

• Archives of Plastic Surgery
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• 제34권5호
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• pp.587-592
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• 2007

Purpose: In case of postburn flexion contracture of the fingers, skin graft, geometrical relaxation techniques, local flap, and free flap have been used. Among these procedures, full-thickness skin grafts from the inguinal area are widely used to reconstruct a postburn flexion contracture in the fingers. But there are many esthetic and functional problems in this procedure. Especially, hyperpigmentation of the skin-grafted fingers poses a troublesome problem, particularly in the patients who have dark colored skin. To solve the problem, we have used pulp graft which was harvested from the lateral aspect of great toe. In the present study, we report pulp graft, with which we have obtained a good result in the treatment of postburn flexion contracture of the fingers. Methods: Between September of 2004 and August of 2006, great toe pulp graft was performed to 20 sites of 15 patients. After release of the postburn flexion contracture using Z-plasty, the composite tissue (pulp) harvested from the lateral aspect of great toe was grafted on the raw surface. Moisture dressing with ointment and foam dressing material was performed. Stratum corneum of the graft got stripped off in two to four weeks after pulp graft. The color of the pulp graft was slightly reddish, then it became similar to the adjacent tissue. Results: There was complete take in all the patients who were treated with pulp graft. Great toe pulp graft provided similar color and texture to the adjacent skin, high rate of graft take, and left only a minimal scar at donor site. Conclusion: Thick keratin layer and inelastic nature of the pulp make this type of the graft much easier and simpler, and ensure a better take. Pulp graft is useful method for the reconstruction of the postburn flexion contracture in fingers.

• Archives of Plastic Surgery
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• 제38권5호
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• pp.655-662
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• 2011

Purpose: The anterolateral thigh flap is versatile flap for soft-tissue reconstruction for defects located at various sites of the body. This useful flap offers a thick and vascular fascia lata component with large amounts that can be soft tissue coverage for different reconstructive purposes. We present our clinical experience with the use of vascular fascia lata, combined with anterolateral thigh flap for various reconstructive goals. Methods: From April 2008 to February 2011, we transferred anterolateral thigh flaps with fascia lata component to reconstruct soft-tissue defects for different purposes in 11 patients. The fascia lata component of the flap was used for tendon gliding surface in hand/forearm reconstruction in 4 patients, for reconstruction medial and lateral patellar synovial membrane and retinaculum in 2 patients, for reconstruction of plantar aponeurosis in the foot in 2 patients, for reconstruction of fascial and peritoneal defect in the abdominal wall in 2 patient, and for dural defect reconstruction in the scalp in the remaining one. Results: Complete loss of the flap was not seen in all cases. Partial flap necrosis occurred in 2 patients. These complications were treated successfully with minimal surgical debridement and dressing. Infection occurred in 1 patient. In this case, intravenous antibiotics treatment was effective. Conclusion: Anterolateral thigh flap has thick vascular fascia with large amounts. This fascial component of the flap is useful for different reconstructive aims, such as for tendon, ligament, aponeurosis defects, abdominal wall or dura reconstruction. It should be considerated as an important advantage of the flap, together with other well-known advantages.