• Journal of Information Display
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• v.2 no.2
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• pp.52-60
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• 2001

The electrical and mechanical properties in indium-tin-oxide films deposited on polymer substrate were examined. The materials of substrates were polyethersulfone (PES) which have gas barrier layer and anti-glare coating for plastic-based devices. The experiments were performed by rf-magnetron sputtering using a special instrument and buffer layers. Therefore, we obtained a very flat polymer substrate deposited ITO film and investigated the effects of buffer layers, and the instrument. Moreover, the influences of an oxygen partial pressure and post-deposition annealing in ITO films deposited on polymer substrates were clarified. X-ray diffraction observation, measurement of electrical property, and optical microscope observation were performed for the investigation of micro-structure and electro-mechanical properties, and they indicated that as-deposited ITO thin films are amorphous and become quasi-crystalline after adjusting oxygen partial pressure and thermal annealing above $180^{\circ}C$. As a result, we obtained 20-25 ${\Omega}/sq$ of ITO films with good transmittance (above 80 %) of oxygen contents with under 0.2 % and vacuum annealing. Furthermore, using organic buffer layer, we obtained ITO films which have a rather high electrical resistance (40-45 ${\Omega}/sq$) but have improved optical (more than 85 %) and mechanical characteristics compared to the counterparts. Consequently, a prototype reflective color plastic film LCD was fabricated using the PES polymer substrates to confirm whether the ITO films could be realized in accordance with our experimental results.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.4
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• pp.359-369
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• 2008

Purpose: Fractures of the mandibular condyle accounts for 15% to 30% of all the mandibular fractures and lots of complications are reported. Among these complications, condylar resorption is the most important one to be taken into account. The purpose of this study is evaluating condylar resorption pattern in relation to extracorporeal fixation technique. Patients & methods: Thirty four patients with 42 mandibular condylar fractures were retrospectively examined with an average follow-up of 18.5 months (6-66 months). Male/female ratio is 27 males (7 bilateral cases) and 7 females (1 bilateral case). Applicated surgical techniques were extracorporeal fixation via submandibular approach and extracorporeal fixation via intraoral approach. We compared radiographic views of post-operative periods with that of most long term follow up in 34 operated sites respectively. Result: There were 2 generalized condylar resorption sites and 3 partial resorption sites with clinical implications. Others (29 joints) showed good healing or satisfactory adaptive state of temporomandibular joints clinically. Radiologically, signs of partial condylar resorption and/or osteoarthrosis were diagnosed in 11 patients. But, 8 out of the 11 patients didn't show significant clinical symptoms, which means successful adaptive remodeling of the surgically located condylar head. Conclusion: From the above results, intentional ramal osteotomy, temporary detachment of the fractured condyle and extracorporeal fixation technique seems to be effective and useful in those cases of condylar fractures in which reduction of the dislocated condyle is very difficult or virtually impossible.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.39
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• pp.29.1-29.5
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• 2017

Background: The surgical extraction of the third molar is the most frequently encountered procedure in oral and maxillofacial surgery and is related with a variety of complications. This study examined the efficacy of intentional partial odontectomy (IPO) in the third molars which have no periapical lesions and are located near important anatomical structures such as inferior alveolar nerve. Methods: Seven patients (four males, three females, $39.1{\pm}11.6years$), who received IPO to reduce the risk of inferior alveolar nerve injury (IANI), were followed long-term. The treated teeth were horizontally impacted third molars in the mandibular left (n = 5) or mandibular right (n = 4) areas and were all ankylosed with the surrounding alveolar bone. During the IPO, the bone around the crown was removed to expose the crown, and then the tooth was resected at cement-enamel junction (CEJ). Any secondary trauma to the healthy root was minimized and remained intact after primary suture. Results: The mean follow-up time was $63.2{\pm}29.8months$, and all sites showed good bone healing after the crown removal. Also, sensory abnormality was not found in any patients after IPO. In one patient, the bone fragments erupted 4 months after IPO. In other patient, an implant placed on second molar site adjacent to the third molar that received IPO was explanted about 2 years after the patient's persistent discomfort. Conclusions: In case where high risk of IANI exists, IPO may be chosen alternatively to surgical extraction to reduce the risk of nerve damage.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.39
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• pp.15.1-15.7
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• 2017

Background: This study constructed a partial-least-square path-modeling (PLS-PM) model and found the pathway by which the postsurgical vertical dimension (VD) affects the extent of the final mandibular setback on the B point at the posttreatment stage for the skeletal class III surgery-first approach (SFA). Methods: This study re-analyzed the data from the retrospective study by Lee et al. on 40 patients with skeletal class III bimaxillary SFA. Variables were obtained from cone beam computed tomography (CBCT)-generated cephalograms. Authors investigated all variables at each time point to build a PLS-PM model to verify the effect of the VD on the final setback of the mandible. Results: From PLS-PM, an increase in $VD_{10}$ was found to decrease the absolute value of the final setback amount of the mandible, which reflects the postsurgical physiological responses to both surgery and orthodontic treatment, which, in turn, can be interpreted as an increase in postoperative mandibular changes. Conclusions: To resolve the issue of collinear cephalometric data, the present study adopted PLS-PM to assess the orthodontic treatment. From PLS-PM, it was able to summarize the effect of increased postsurgery occlusal vertical dimension on the increased changeability of the B point position at the posttreatment stage.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.616-620
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• 2011

Purpose: Mayer-Rokitansky-Kuster syndrome (MRK) is second common cause of primary amenorrhea. It is a syndrome of vaginal aplasia and Mullerian duct anomaly. Vaginal aplasia varies from agenesis of whole vagina to aplasia of upper 2/3. For reconstructing vagina, various methods are introduced. Gracilis myocutaneous flap was the first attempt in that the flap is used in vaginal reconstruction. Various flap-based vaginal reconstruction methods have been introduced. Modified Singapore flap (pedicled neurovascular pudendal thigh fasciocutaneous flap) is one of those methods that used posterior labial artery as pedicle, and pudendal nerve branch as sensory root. As its donor lies on inguinal crease that is easily hidden and there are benefits on sexual intercourse by early sensory recovery, authors think that modified Singapore flap is effective for young MRK syndrome patients. Methods: Eight patients underwent surgery between 2008 and 2010. The flap was designed on both groin area with external pudendal artery branch as a pedicle. All flaps were fixated in pelvic cavity with absorbable suture, and additional compression on neovaginal wall was supplied by polyvinyl alcohol sponge ($Merocel^{(R)}$). Results: All patients were successfully reconstructed without flap related complications such as congestion or partial flap loss. The average size of the flap (each side) was 69.34 $cm^2$. Polyvinyl alcohol sponge ($Merocel^{(R)}$) was inserted into neovagina for 5 days on every patient. One case of rectal laceration was occurred while making pelvic pocket by OBGY team. Other complications such as lumen narrowing, wound contracture or vaginal prolapsed were not reported during 8 months of follow up. Conclusion: Modified Singapore flap is a sensate fasciocutaneous flap that is thinner than other myocutaneous flap such as VRAM, and more durable over skin graft. Therefore this is a good choice for vaginal reconstruction in MRK syndrome. And known complications of Modified Singapore flap could be reduced with careful procedure and mild compression techniques.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.578-582
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• 2009

Purpose: In extensive deep burn of the lower limb, due to less amount of soft tissue, bone is easily exposed. When it happens, natural healing or reconstruction with skin graft only is not easy. Local flap is difficult to success, because adjacent skins are burnt or skin grafted tissues. Muscle flap or free flap are also limited and has high failure rate due to deep tissue damage. The authors acquired good outcome by performing one - stage operation on bone exposed soft tissue defect with AlloDerm$^{(R)}$(LifeCell, USA), an acellular dermal matrix producted from cadaveric skin. Methods: We studied 14 bone exposed soft tissue defect patients from March 2002 to March 2009. Average age, sex, cause of burn, location of wound, duration of admission period, and postoperative complications were studied. We removed bony cortex with burring, until conforming pinpoint bone bleeding. Then rehydrated AlloDerm$^{(R)}$(25 / 1000 inches, meshed type) was applicated on wound, and thin split thickness(6 ~ 8 / 1000 inches) skin graft was done at the immediately same operative time. Results: Average age of patients was 53.6 years(25 years ~ 80 years, SD = 16.8), and 13 patients were male(male : female = 13 : 1). Flame burn was the largest number. (Flame burn 6, electric burn 3, contact burn 4, and scalding burn 1). Tibia(8) was the most affected site. (tibia 8, toe 4, malleolus 1, and metatarsal bone 1). Thin STSC with AlloDerm$^{(R)}$ took without additional surgery in 12 of 14 patients. Partial graft loss was shown on four cases. Two cases were small in size under $1{\times}1cm$, easily healed with simple dressing, and other two cases needed additional surgery. But in case of additional surgery, granulation tissue has easily formed, and simple patch graft on AlloDerm$^{(R)}$ was enough. Average duration of admission period of patients without additional surgery was 15 days(13 ~ 19 days). Conclusion: AlloDerm$^{(R)}$ and thin split thickness skin graft give us an advantage in short surgery time and less limitations in donor site than flap surgery. Postoperative scar is less than in conventional skin graft because of more firm restoration of dermal structure with AlloDerm$^{(R)}$. We propose that AlloDerm$^{(R)}$ and thin split thickness skin graft could be a solution to bone exposured soft tissue defects in extensive deep burned patients on lower extremities, especially when adjacent tissue cannot be used for flap due to extensive burn.

• Computers and Concrete
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• v.18 no.6
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• pp.1083-1096
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• 2016

Beam-column joints are recognized as the weak points of reinforcement concrete frames. The ductility of reinforced concrete (RC) frames during severe earthquakes can be measured through the dissipation of large energy in beam-column joint. Retrofitting and rehabilitating structures through proper methods, such as carbon fiber reinforced polymer (CFRP), are required to prevent casualties that result from the collapse of earthquake-damaged structures. The main challenge of this issue is identifying the effect of CFRP on the occurrence of failure in the joint of a cross section with normal ductility. The present study evaluates the retrofitting method for a normal ductile beam-column joint using CFRP under monotonic and cyclic loads. Thus, the finite element model of a cross section with normal ductility and made of RC is developed, and CFRP is used to retrofit the joints. This study considers three beam-column joints: one with partial CFRP wrapping, one with full CFRP wrapping, and one with normal ductility. The two cases with partial and full CFRP wrapping in the beam-column joints are used to determine the effect of retrofitting with CFRP wrapping sheets on the behavior of the beam-column joint confined by such sheets. All the models are subjected to monotonic and cyclic loading. The final capacity and hysteretic results of the dynamic analysis are investigated. A comparison of the dissipation energy graphs of the three connections shows significant enhancement in the models with partial and full CFRP wrapping. An analysis of the load-displacement curves indicates that the stiffness of the specimens is enhanced by CFRP sheets. However, the models with both partial and full CFRP wrapping exhibited no considerable improvement in terms of energy dissipation and stiffness.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.1
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• pp.94-99
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• 2017

Nowadays, digital dentistry is generally applied to prosthodontics with fabrication of inlays or any other fixed prostheses by utilizing CAD/CAM (computer-aided design/computer-aided manufacturing) technology and intraoral scanner. However, in fabricating removable prosthesis, there are some limitations for digital technology to substitute conventional casting method. Therefore, approaching removable prostheses fabrication with CAD/CAM technology would be a meaningful trial. In this case report, Kennedy class III mandibular edentulous patient who was in need of increasing the vertical dimension of occlusion was treated with removable partial denture using CAD and rapid prototyping technique. Surveying and designing the metal framework of the partial denture was performed with CAD, and sacrificial plastic pattern was fabricated with rapid prototyping technique. During the follow up period of nine months, the removable partial denture has provided satisfactory results in esthetics and function.

• Archives of Craniofacial Surgery
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• v.11 no.1
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• pp.13-18
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• 2010

Purpose: Nasal defect can be caused by excision of tumor, trauma, inflammation from foreign body reaction. Nose is located in the middle of face and protruded, reconstruction should be done in harmony with size, shape, color, and textures. We report various methods of nasal reconstruction using local flaps. Methods: From March 1998 to July 2008, 36 patients were operated to reconstruct the nasal defects. Causes of the nasal defects were tumor (18 cases), trauma (11 cases), inflammation from foreign body reaction (5 cases) and congenital malformation (2 cases). The sites of the defects were ala (22 cases), nasal tip (8 cases) and dorsum (6 cases). The thickness of the defects was skin only (5 cases), dermis and cartilagenous layer (7 cases) and full-thickness (24 cases). According to the sites and thickness of the defects, various local flaps were used. Most of alar defects were covered by nasolabial flaps or bilobed flaps and the majority of dorsal and tip defects were covered by paramedian forehead flaps. Small defects below $0.25 cm^2$ were covered with composite graft or full-thickness skin graft. Results: The follow-up period was 14 months. Partial flap necrosis was observed in a case, and one case of infection was reported, it was improved by wound revision and antibiotics. Nasal reconstruction with various local flaps could provide satisfactory results in terms of color and texture match. Conclusion: The important factors of nasal reconstruction are the shape of reconstructed nose, color, and texture. Nasolabial flap is appropriate method for alar or columellar reconstruction and nasolabial island flap is suitable for tip defect. The defect located lateral wall could be reconstructed with bilobed flap for natural color and texture. Skin graft should be considered when the defect could not afford to be covered by adjacent local flap. And entire nasal defect or large defect could be reconstructed by paramedian forehead flap.

• Archives of Reconstructive Microsurgery
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• v.20 no.1
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• pp.1-7
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• 2011

The aim of extremity reconstruction has focused on early wound coverage and functional recovery but rarely aesthetics. As the quality of life improves, however, the request for aesthetics has been growing. The authors has conducted retrospective reviews on the 86 cases that had extremity reconstruction using free flap, considering the characteristics of parts that had been assessed in primary operation between May 1996 and December 2010. Aesthetic grading was performed in four categories; color, texture, contour and marginal scar. Recipient sites were 42 hands, 19 feet, 14 lower extremities excluding feet and 10 upper extremities apart from the hand. Types of free flap were 16 latissimus dorsi free flaps, 13 anterolateral thigh free flaps, 12 dorsalis pedis free flaps, 8 transvers rectus abdominis free flaps, 7 gracillis free flaps, and 5 superficial temporal fascia free flaps. Total flap necrosis was seen in 8 cases(9.3%) and partial necrosis in 5 cases(5.8%). Secondary revision was done in 24 cases(27.9%) and the most common revision, debulking was done in 14 cases(16.3%). The authors has considered cosmetic aspects along with wound coverage and functional recovery in primary reconstruction. The results of aesthetic grading was 16.2 out of 20, and the secondary revision rate was reduced.