• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.1
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• pp.11-18
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• 1996

Grown-in defects like OISF and FPD in the large diameter(> 8 inch)of silicon crystal are characterized. It was revealed that the presence of the ring-patterned OISF would deterorate the minority life time of the silicon crystal. Through the cooling experiment from the $1250^{\circ}C$, the nucleation of the OISF was confirmed to follow the homogeneous nucleation and growth process. In addition to OISF nucleus, crystal originated particle, which was known to be closely related with FPD (Flow Pattern Defects), was found to depend on the pulling rate of the crystal. Combination of the lower rate of the pulling and the faster cooling near the $950^{\circ}C$ is proposed to be effective method in reducing the generation of these grown-in defects.

• Archives of Craniofacial Surgery
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• v.22 no.5
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• pp.232-238
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• 2021

Background: Galeal or temporalis muscle flaps have been traditionally used to reconstruct skull base defects after tumor removal. Unfortunately, these flaps do not provide sufficient vascularized tissue for a dural seal in extensive defects. This study describes the successful coverage of large skull base defects using anterolateral thigh (ALT) free flaps. Methods: This retrospective study included five patients who underwent skull base surgery between June 2018 and June 2021. Reconstruction was performed using an ALT free flap to cover defects that included the intracranial space and extended to the frontal sinus and cribriform plate. Results: There were no major complications, such as ascending infections or cerebrospinal leakage. Postoperative magnetic resonance imaging showed that the flaps were well-maintained in all patients. Conclusion: Successful reconstruction was performed using ALT free flaps for large anterior skull base defects. In conclusion, the ALT free flap is an effective option for preventing communication between the nasal cavity and the intracranial space.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.67-70
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• 2008

This paper deals with the effect of radial parameters in cogging process such as reduction in height (Rh) and rotational angle ($\theta$) of a billet on a void closure for large forged products. Usually closing and consolidation of internal void defects in a ingot is a vital matter when utilized as large forged products, using a press with limited capacity and the sizes of the ingots becoming larger. Consequently, it is important to develop cogging process for improvement of internal soundness without a void defect and cost reduction by solid forging alone with limited press capacity. For experiments of cogging process, hydraulic press with a capacity of 800 ton was used together with a small manipulator which was made for rotation and overlapping of a billet. Size of a void was categorized into two types; $\emptyset$ 6.0 mm and $\emptyset$ 9.0 mm to investigate the change of closing and consolidation of void defects existed in the large ingot during the cogging process. Also open void and closed void in the ingot were tackled to show the differentiation of closing process of internal voids with respect to void sizes. In this paper systematic configuration for closing process of void defects were expressed based on this experiment results in the cogging process.

• Archives of Reconstructive Microsurgery
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• v.11 no.1
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• pp.11-18
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• 2002

Large soft tissue defects around the knee joint are known to significantly diminish joint function. Severe soft tissue defects on the anterior aspect of the knee joint especially bring on significant joint motion limitation. Although simple split skin grafts can cover the skin defect, the progressing scar contracture of the grafted skin causes joint stiffness. One of the best solutions of large soft tissue defects around the knee joint is covering the defect with a good quality skin flap. Separated flaps with one vascular pedicle are good candidates for covering anterior and posterior aspects of the joint for example. Authors performed 12 cases of combined scapular and latissimus dorsi free flaps from 1984 to 2000. Among them, we experienced 5 cases of knee joint defect covering using the double free flap for coverage of the soft tissue defect with preservation of the knee joint function and satisfactory results. The system of flaps based on the subscapular artery and vein provides a variety of composite free flaps. The possible flaps that can be harvested based on this single vascular pedicle include the scapular and parascapular skin flap, the serratus anterior and latissimus dorsi muscular flap, the lateral scapular bone flap, the latissimus dorsi-rib flap, and the serratus anterior-rib flap. This combined flap is available for multiple tissue defects or complex defects because it can be incorporated with skin, muscle and bone flaps. A main advantage is the independent vascular pedicles of each component, which allow freedom in orientation of each components. Consequently it can be freely applied to any form of three dimensional defects on the upper and lower extremities. The combination of scapular cutaneous flap and latissimus dorsi musculocutaneous flap can be resurfaced for massive cutaneous defects on the extremities. We report the use of the combined scapular and latissimus dorsi free flap in five patients to reconstruct massive defects on the extremities with resultant improved joint function. There was no flap failure and minimal complications and disadvantages. The anatomy of this flap is reviewed and the indication and advantages are discussed. All of the five flaps survived and there was no scar contracture affecting the joint motion.

• Archives of Craniofacial Surgery
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• v.22 no.6
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• pp.296-302
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• 2021

Background: The reconstruction of large full-thickness alar defects requires complex surgical procedures that are usually performed in two stages, with concomitant disadvantages in terms of patient trauma, surgical risk, and cost. This study presents a functional folded nasolabial island flap (FNIF) that can be used to repair large-sized full-thickness alar defects in a straightforward manner. Methods: This retrospective study included seven patients who received a FNIF for a full-thickness alar defect between January 2007 and December 2020. The FNIF is different from the conventional nasolabial flap in that it is folded and twisted to achieve nostril reconstruction with a satisfactory three-dimensional mucosal lining in a single stage. The cosmetic and functional results of FNIF were evaluated by both patients and physicians. Results: The age ranged from 51 to 82 years (mean, 65.6 years). The causes of the defects were squamous cell carcinoma, basal cell carcinoma, and trigeminal trophic syndrome. The nostril lining did not collapse, there was no hypertrophic scarring, and air movement through the nostrils on the flap side was normal. Overall, FNIF produced excellent aesthetic and functional outcomes, with minimal patient discomfort. There were no postoperative complications. Conclusion: Compared with existing reconstruction methods for large full-thickness alar defects, FNIF can easily achieve aesthetic and functional success in a single-stage procedure. It provides satisfactory results for both the patient and the surgeon.

• Archives of Plastic Surgery
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• v.34 no.6
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• pp.753-758
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• 2007

Purpose: Penoscrotal extramammary Paget's disease is a rare cutaneous malignancy that primarily affects the elderly. To prevent local recurrence, adequate surgical excision with its intraoperative frozen section, proper reconstruction, and careful follow-ups are required. The present study describes the treatment of patients with penoscrotal extramammary Paget's disease, focusing on the reconstruction after the ablation of lesion. Methods: Nine patients were selected who had undergone a local pedicle flap procedure due to the large defects after ablation of extramammary Paget's disease of the penoscrotal area, during the period of 1999 to 2005. Wide excision combined with intraoperative frozen sectioning was performed, and the penoscrotal wound was reconstructed with a local skin flap. Three flaps were chosen depending on the size of the defect. If the defect size was small and the scrotal tissue was adequate, scrotal flap(n=5) was enough for its reconstruction. However, as there were large defects with insufficient remnant scrotal tissue, a groin flap(n=2) or an anterolateral thigh flap(n=2) were performed. Results: There were no complications with the postoperative wound. Furthermore, no local recurrence was noted during two to six years of follow-up period (mean average 3.7 years). Conclusion: For the resurfacing the penoscrotum at large defects after ablation of extramammary Paget's disease, we performed reconstruction with a local flap. In the aspect of both function and cosmetic concerns, the results were satisfactory.　

• Journal of Trauma and Injury
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• v.31 no.2
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• pp.91-95
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• 2018

Managing large infected midline abdominal defects are clinically challenging and technically demanding. The alloplastic materials, regional flaps, and component separation are usually infeasible because of the size, location, depth, and state of the defects. In these cases, the free flap is the only option with a large well-vascularized tissue that is free to inset regardless of the location. Herein, we report a case of 44-year-old man with a large infected midline abdominal wall defect who was completely treated with a latissimus dorsi myocutaeous free flap followed by negative pressure wound therapy.

• The Journal of Advanced Prosthodontics
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• v.2 no.3
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• pp.65-70
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• 2010

Large oro-facial defects result from cancer treatment consequences in serious functional as well as cosmetic deformities. Acceptable cosmetic results usually can be obtained with a facial prosthesis. However, retention of a large facial prosthesis can be challenging because of its size and weight. This article describes prosthetic rehabilitation of a 57-year-old man having a right lateral mid-facial defect with intraoral-extraoral combination prosthesis. A modified technique to fabricate a hollow substructure in heat-polymerizing polymethyl-methacrylate to support silicone facial prosthesis was illustrated. The resultant facial prosthesis was structurally durable and light in weight facilitating the retention with magnets satisfactorily. This technique is advantageous as there is no need to fabricate the whole prosthesis again in case of damage of the silicone layer because the outer silicone layer can be removed and re-packed on the substructure if the gypsum-mold is preserved.

• Archives of Reconstructive Microsurgery
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• v.9 no.1
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• pp.80-87
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• 2000

Acute high speed accidents that results in full thickness skin defect and exposure of tendon, nerve, vessel and periosteum over denuded bone demands soft tissue coverage. Exposed bone often ensues chronic infection and requires free flap transplantation which surely covers defects in one stage operation and enhances transport of oxygen-rich blood and converts a non-osteogenic or partially osteogenic site into a highly osteogenic site, but exposed bone which had performed free flap transplantation sometimes necroses and needs secondary bone procedure. Scar contracture limits joint motion should be excised and covered with normal soft tissue to restore normal range of motion. Authors have performed the large latissimus dorsi myocutaneous free flap in 8 cases of extensive soft tissue defect and exposed bone lesion in the leg and 1 case of the flap was failed. The secondary ilizarov bone procedure was performed in 3 of 8 cases. 2 cases of large burn scar contracture and 1 case of posttraumatic scar contracture in lower extremity were restored with the large latissimus dorsi myocutaneous free flap. Authors concluded that large latissimus dorsi myocutaneous free flap is the most acceptable microvascular procedure in large soft tissue defect combined with exposed periosteum and bone requiring secondary bone procedure and in large burn scar contracture limiting knee joint motion.

• Journal of Chest Surgery
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• v.27 no.5
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• pp.422-426
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• 1994

Recently, we experienced one case of multiple ribs fracture with large chest wall defects. This patient was treated with internal fixation of ribs by use of Judet`s struts and reconstruction of chest wall defects by use of Teflon mesh. Postoperative outcome was satisfactory result and its advantages were reduced duration of operation, prevention of pulmonary herniation and reduced risk of postoperative infection.