• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.05a
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• pp.214-214
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• 2003

During a model test of Hutton TLP, a "ringing" response was first observed about 20 years ago. This phenomenon is a resonant build up over the time of wave period and this burst-like motion can cause the extreme load on the TLP tether. It is often detected in the large and steep irregular waves but the generation mechanism leading to the "ringing" is not yet well understood. According to the research since then, the higher order harmonic components may account for the "ringing" on the floating offshore structures. The main purpose of the present research is, thus, to measure the higher harmonic forces exerted on a vertical truncated circular column and to compare them with available data. A vertical truncated cylinder with a diameter of 3.5inch and a draft of 10.5inch is used as a test structure, which is a scaled model of ISSC TLP column. The cylinder is installed at a distance of 45ft from the wave maker in order to avoid parasitic waves created in the wave flap. Attached to the upper part of the cylinder are two force gages to measure the horizontal (surge) and vertical (heave) forces on the cylinder. The incoming waves are Stokes waves with a slope ranging from 0.06 to 0.24. The forces and waves are measured for 60 seconds with a sampling rate of 50 Hz. Among the recorded data, the first 10 waves are excluded because of transient behavior of the waves and the next The horizontal and vertical forces are analyzed up to 5th order harmonics. The horizontal forces are then compared to the values from the theoretical model called "FNV model". In addition, force transfer functions are also investigated. Major findings in this research are below. 1) The first order forces measured are slightly larger than the theoretical values of "FNV model" 2) The "FNV model" considerably overpredicts the second order forces. 3) The larger the amplitude and more extreme the wave slope, the smaller the predictions are compared to the experimental. 4) The higher harmonic forces are significantly smaller than the first harmonic force for all wave parameters. 5) The normalized forces vs. waves slopes are almost constant in the lower harmonics but vary a lot in the higher harmonics. 6) The trend of forces is more nonlinear in the horizontal forces than in the vertical forces as the wave slope increases. 7) The part of the results above is also observed by other researchers and confirmed again through the present work.

• Journal of Periodontal and Implant Science
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• v.31 no.2
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• pp.345-356
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• 2001

The purpose of the present study was to evaluate the clinical efficacy of guided tissue regeneration(GTR) using resorbable polylactic/polyglycolic copolymer(PLA/PGA) membrane in mandibular class II furcation involvement and to compare it to the clinical efficacy of only flap operation. Both procedures were conducted in 5 patients with class II furcation involvements. After 6 months of follow up, the probing pocket depth, clincial attachment level, bone probing depth, and radiographic changes were compared, and the following results were obtained: 1. GTR using PLA/PGA demonstrated a statistically significant reduction in probing pocket depth and bone probing depth, and the control group demonstrated a statistically significant reduction in bone probing depth. 2. The comparison between the experimental and control group failed to demonstrate statistically significant difference in clinical improvement, but more reduction in probing pocket depth and bone probing depth were observed in the experimental group. The probing pocket depth and the bone probing depth were $2.2{\pm}1.6mm$ and $2.4{\pm}1.1mm$ respectively in the control group, while they were $2.4{\pm}1.3mm$ and $3.0{\pm}1.2mm$ respectively in the experimental group. 3. Radiographic change was not detectable for the both groups during the 6 months of follow up. 4. Sites with deeper probing pocket depth at baseline examination showed greater amount of clinical improvement in both groups. Other clinical factors didn't have any significant effect on the treatment results. It is concluded that though there are some limitations, PLA/PGA membrane is effective for the treatment of mandibular class II furcation involvement.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.531-537
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• 2009

Purpose: Alveolar bone grafting has become an essential process in the treatmemt of alveolar cleft patient for stabilization of the maxillary arch, elimination of oronasal fistula, the reconstruction of the soft tissue nasal base support, and creation of bony support for tooth eruption for implant. The use of Autologous iliac cancellous bone is preferable because of the adequate quantity and high osteoinductive potential. However, even with iliac bone, insufficient osteoregeneration and absorption occur due to several factors such as the patient's age, cleft width, functional stress, and others. In order to increase osteoregeneration where the iliac bone is placed, the present study is associated with bone marrow aspirate (BMA). The experimental study evaluated the efficacy of osteoregeneration in normal cleft rabbits when alveolar bone grafting was performed with autologous iliac corticocancellous bone. Methods: Twenty - four New Zealand White rabbits were divided randomly into 2 groups (BMA, control). All animals underwent harvesting of corticocancellous bone graft from the right posterior iliac crest via standard surgical technique. $1m{\ell}$ of BMA were obtained by scraping the needle and aspirate with $10m{\ell}$ syringe from the contralateral iliac bone wall. The muco - periosteal flap on the palate was elevated. A mixture of Equal bone's volumes with BMA and saline as its control was inserted into the cleft. Animals were sacrificed at 2, 4, and 8 weeks and maxilla was harvested for dental peri - apical X-ray, bone matrix density (BMD),and histologic analysis. Result: BMD of regenerated bone to the cleft in the rabbits was higher than that of the control rabbits. X-ray, histologic analysis showed that increased osteoregeneration and low absorption rate were observed in the BMA group. Conclusion: Our experimental study showed BMA enhanced the osteoregeneration and survival rate of alveolar bone grafting. BMA is easy to extract & cost - time effective. So it can be an effective enhancers for bone grafting mixtures.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.611-616
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• 2009

Purpose: The rate of fistulas occuring followed by resection of oral cavity, oropharyngeal, hypopharyngeal, and laryngeal cancer are reported to be 9 ~ 23% according to various documents. Neglected treatment of the fistula can result in a setback in proper treatment with restrictions in oral intake leading to delayed return to daily life. Furthurmore, in severe cases, it may injure important vessels and adjacent structures of the neck area. The author reviewed previously reported cases of treatment methods for fistulas recurring after diverse head and neck operations and with sharing the treatment experiments of our patients, we tried to present a treatment algorism for different fistula types. Methods: Our study was based on retrograde analysis of 64 patients who were clinically diagnosed with fistula after operation for cancer of the head and neck from 1997 to 2008 at Severance Hospital. Their primary sites of cancer were 8 oral cavity, 22 oropharynx, 25 hypopharynx, and 9 larynx. The patients were aged 45 to 75 years and the male to female ratio was 11 to 1. The patient's operation records and progress notes were evaluated for determination of degree of fistula and treatment methods. Results: Most fistulas were clinically suspected after postoperative 5 days and symptoms noted for detection of the fistula were erythema, purulent discharge, edema, tenderness, and fluctuation. The fistula was definitely diagnosed at postoperative 2 weeks with barium test and treatment method ranging from conservative management to operative procedure were applied to each patients. Total 21 patients were managed with conservative protocol. In 15 cases, direct repair of the fistula was done and more stable repair of the fistula was possible with using of TachoComb$^{(R)}$. Pharyngostoma was performed in 14 patients. Among them, 4 patients healed spontaneously, 5 patients were taken direct closure, 4 patients were taken pectoralis major musculocutaneous flap, and one patient was taken esophageal transfer. The other 14 patients were taken 11 pectoralis major musculocutaneous flaps and 3 free flaps without pharyngostoma formation. Conclusion: Fistula is a troublesome complication resulting after resection of head and neck cancer. Early detection and adequate treatment according to the period and condition of the fistula may prevent further complications and reduce the pain of the patient.

• Journal of Veterinary Clinics
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• v.30 no.2
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• pp.146-149
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• 2013

A 6-month-old, intact male Great Pyrenees (35 kg) was referred with 2 weeks continuous left forelimb lameness to the Chonbuk Animal Medical Center, College of Veterinary medicine, Chonbuk National University. The lameness became worse three days before being referred to the hospital. Upon the physical examination, the patient had pain when the left shoulder joint was palpated, and the lameness was visible in the left forelimb during ambulation on gait examination. There were no remarkable findings on radiological and neurological examination. Osteochondritis dissecans (OCD) was suspected based on medical history and gait tests. As a definitive diagnosis could not be made, exploratory arthroscopic surgery was performed to examine the inside of the shoulder joint. During the operation, mild bicipital tenosynovitis, synovitis and OCD which was located on the caudal medial area of humeral head were revealed. Arthroscopic procedures were used for the treating OCD, including the removal of the OCD flap and debriding of the subchondral defect until hemorrhaging by use of an electrical burr. The patient was discharged a day after surgery. After 2 weeks, the patient again presented at the hospital due to complications, including inflammation of the surgical lesion because of licking and seroma within the subcutaneous tissue. Antibiotics were administered and an aseptic bandage was applied. And simple surgical operations were performed for the removal of the cyst and seroma. Eleven weeks following arthroscopy, the lameness was completely resolved. Arthroscopy has the advantage of allowing gross examination inside the joint capsule. Due to this advantage, arthroscopy is one of the best advanced options for diagnosis in dogs with undiagnosed joint pain.

• Korean Journal of Ichthyology
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• v.35 no.3
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• pp.171-176
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• 2023

The olfactory organ of Carassius auratus and C. cuvieri was compared morphologically and morphometrically using stereomicroscopy and statistical program (SPSS version 18.0). The external morphology of the olfactory organ consists of the open semicircular anterior and posterior nostril, and nasal flap. The internal structure showed the oval rosette consisting of several lamellae arranged radiately. In statistical analysis of standard length (SL), olfactory lamellar number (LN), and SL/LN ratio between two species using independent two sample t-test and Pearson's correlation and coefficient, C. cuvieri is the longer SL than that of C. auratus and C. auratus LN (14~20) is lager than that of C. cuvieri (14~16) (P<0.001) and C. auratus LN/SL ratio (12.7±0.7%) is larger than that of C. cuvieri (8.2±0.6%). These results suggest that i) open semicircular nostrils is functional morphology to offset the boundary layer and ii) the lager LN of smaller C. auratus may be a morphological adaptation to reflect its higher olfactory dependence than C. cuvieri and iii) such interspecific difference in LN and LN/SL ratio could be applied as a new taxonomic trait for identification.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.25 no.4
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• pp.281-294
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• 1999

Vasospasm causes microvascular surgery to fail as a main factor in the loss of transferred flap dye to the diminution of blood flow in reconstruction surgery. Although there has been extensive research to resolve the vasospasm problem, no one has reached an ideal solution to date. However, cryotherapy, which is often used for destruction of tumor lesions, is being presented as a new way of releasing vasospasm. After making a histomorphometric measurement on vasodialation during the course of 1, 3 and 7 days, 2 and 4 weeks, and 5 months periods and observing the change of blood vessel in a histologic, immunohistochemical, and scanning electronic microscopic approach, the results were as follows : 1. Vascular inner diameters of the experimental 1 and 3 days groups were measured $476.3{\pm}28.20{\mu}m$, $497.15{\pm}48.79{\mu}m$ respectively showing statistically meaningful vasodilation(P<0.05), which continued by the experiment 4 weeks group. However, in the experimental 5 months group, the vascular inner diameter appeared similar to the control groups. Even though the thickness of smooth muscular layers come out to be thinner in all the experimental groups compared to the control group, it was difficult to find any statistical meaningfulness. In addition, the vascular external diameters of every experimental groups were shown to be longer than the control group. 2. In light microscopic view, severe injury was evident on the smooth muscular layer cell from the experimental 1 day group, started recovering partially from the experimental 7 days group, and was mostly restored in the experimental 4 weeks group and layer of adventitial stripping were nearly recoverd 2 weeks group. 3. The PCNA positive cells of smooth muscular layer were observed from the experimental 7 days group and had a tendency to increase by the experimental 2 weeks group. In the experimental 4 weeks and 5 months group, the number of PCNA possitive cells observed was comparable to the control group. 4. ${\alpha}$-SMA level of smooth muscular layer cells, having been significantly lower than the control group in the severly damaged experimental 1 day group. It was seen to be increased in the experimental 7 days group and turned out to show similar ${\alpha}$-SMA level in 4 weeks to the control group. 5. In the view of SEM, the endothelial cells were destructed and falling off, and also present the appearance of flattening in the experiment 1 day group. The endothelial layer cells started partially recovering from the 7 days group after the freezing injury. On 4 weeks and 5 months, the endothelial cells were fully coverd the damaged area, also it's appearance is similar to control group. In conclusion, the vascular freezing after the removal of adventitia caused damages to smooth muscular layer cells, and brought about vasodilation, which continued by the 4th week. The smooth muscular layer cells started partially reviving from the 7rd day after the damage by vascular freezing, and recovered their similar figure to the control group's 4 weeks later. This was considered the result of cells which surround the damaged blood vessel being influxed into the smooth muscular layers. Therefore, this local freezing injury on the blood vessel was thought to be applied clinically to relieve severe vasospasm which cannot be treated by vasodilation drug, a microvascular surgery.

• The Journal of the Korean bone and joint tumor society
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• v.11 no.2
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• pp.141-147
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• 2005

Purpose: The most important thing in curing Malignant melanoma is surgical excision, operating method is wide excision. The author et al. studied 5-year survival rate of each stage and appropriate surgical margin after operating wide excision and immuno-chemotherapy. Materials and methods: From March 1995 to August 2003, wide excision and immunochemotherapy were operated to 35 patients (17 males and 18 females) who were diagnosed as malignant melanoma and followed up. Excision was done around 2 cm from edge of tumor regardless of the size or effected degree of the skin, and flap or full thickness skin graft was used for skin deficit that was not covered after excision. As for immuno-chemotherapy, method that prescribes 400 mg of dacarbazine (DTIC) and 3 million IU of interferone-${\alpha}$ in combination was used. Immuno-chemotherapy was operated to patients in over stage III. We used AJCC stage that was revised in 2002. Local recurrence, local metastasis and distant metastasis were investigated for these patients as well as the 5-year survival rate of each stage. Results: Most frequently 15 cases(42.8%) occurred in foot, 5 cases(14.2%) occured in ankle, 2 cases(5.7%) in leg, 2 cases(5.7%) in thigh and 5 cases(14.2%) in hand. The incidence of each stage were 8 cases(22.8%) in IA, 9 cases(25.7 %) in IB, 4 cases(11.4%) in IIA, 2 cases(5.7%) in IIB, 1 cases(2.8%) in IIIA, 2 cases(5.7%) in IIIB, 2 cases(5.7%) in IIIC and 7 cases(20.0%) in stage IV. 5-year survival rate of each stage were 94.1% in stage I, 66.8% in stage II, 40% in stage III and 14.3% in stage IV. Conclusion: 5-year survival rate of stage IV was low in malignant melanoma. In treatment of malignant melanoma, staging before operation is important as operation methods are different from each stage. We recommend wide excision which remove around 1~3 cm from margin of tumor up to each thickness.

• The korean journal of orthodontics
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• v.31 no.3 s.86
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• pp.369-379
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• 2001

The aim of this study was to investigate the periodontal response according to the timing of orthodontic force application after bone graft into the angular bony defect. Nine dogs were divided into three groups, 2, 4, and 6 weeks, according to the timing of orthodontic force application after bone graft. Periodontal angular bony defects were created surgically at the distal aspect of both maxillary third incisors. Two weeks later, flap operation was performed to eliminate inflammation and reference notch was made on the root surface at the level of the bottom of each defect. Demineralized freeze-dried bone was implanted on the left side whereas only debridement was done on the other side. Experimental tooth movement was executed during 8 weeks on both graft and non-graft sides. After 2 weeks of retention period, animals were sacrificed for histologic specimens. The results were obtained as follows 1 New bone formation was more pronounced in the graft side than in the non-grad side in all experimental animals. 2. In the 6-week group, new bone and cementum formation was observed in more than half from the notch to the cemento-enamel junction, and the zone of connective tissue attachment was found without apical migration of junctional epithelium. 3. In the 4-week group, the amount of new bone formation was smaller than in the 6-week group whereas the overall remodeling pattern was similar. 4. New bone formation was confined to around the notch and the junctional epithelium migrated apically to the level of the notch with no connective tissue attachment and cementum formation in the 2-week group. The results of the present study suggest that periodontal response may be influenced by the timing of orthodontic force application after bone graft into angular bony defect.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.1
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• pp.11-19
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• 2013

Purpose: The aim of this study was to evaluate the heat generation in bone in vitro during the guided flapless drilling procedure and the effect of drilling methods on the heat generation. Materials and methods: A model that has missing the first and second mandibular molars bilaterally was used. In group A, classical flap implant surgery was performed. In group B, flapless implant surgery using surgical guide was performed. In group C, flapless implant surgery using surgical guide without up-and-down pumping motion was performed. Temperature was measured with k-type thermocouple and a real-time digital thermometer. The thermocouples were placed at 0.5 mm away from the osteotomy area at the depths of 3 mm and 6 mm. The measured values were evaluated with independent t-test. Results: The mean temperature generated was $27.2^{\circ}C$ ($SD{\pm}2.1^{\circ}C$) and $27.5^{\circ}C$ ($SD{\pm}2.3^{\circ}C$) for groups A and B, respectively. These differences were not statistically significant. In group C, the mean temperature was $37.0^{\circ}C$ ($SD{\pm}3.4^{\circ}C$). There were statistically significant differences between groups B and C with respect to the mean temperature. Conclusion: These findings suggest that guided flapless drilling with up-and-down pumping motion may not significantly increase the bone temperature.