• Journal of Periodontal and Implant Science
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• v.29 no.2
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• pp.355-373
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• 1999

Many researches have been reported that collagen as cellular stroma, matrix of grafting materials, mediator of agents for the purpose of promoting healing process invivo, but the responses in vivo were seen various. The goal of this experiment is to assess the effect of collagen on bony healing, through histological evaluation of implanted collagen on the calvarial defect in rats. 2-month-old Sprague-Dawley, 24 rats were used and 12 rats assigned to each group of control and test. Defect of 5mm in diameter was made on the calvarial bone with trephine bur. Following thorough saline rinse, defect of control group was left in empty and that of experimental group was filled with fibrillar collagen($COLLATAPE^{(R)}$, COLLA-TEC. INC. U.S.A.) soaked in saline. 3 rats in each group were sacrificed at 3, 7, 14, 21 days after operation respectively, and the tissue blocks were prepared for light microscope with H-E for evaluation of overall healing, with TRAP(tartrate resistant acid phosphatase) for evaluation of osteoclastic activity and with immunohistochemical staining for macrophages. The results were as follows : 1. In the control group, inflammatory responses were disappeared at day 14, but, in the experimental group inflammatory infiltrates were reduced at day 21. Thus, the experimental group showed more severe soft tissue inflammation than control group. 2. Both control and experimental group showed slight appositional growth at day 7 and gradual bony growth to 21th day. But, complete bony healing of the defect was not shown. There was no significant difference in bony healing between control and experimental group 3. Specific response of macrophages for implanted collagen was observed at day 14 in the experimental group. In conclusion, although fibrillar collagen caused inflammation of soft tissue during initial healing period, inflammatory responses by fibrillar collagen didn't inhibit bony regeneration and implanted collagen was biodegradaded by macrophages. Thus, we expect that fibrillar collagen can be used for useful mediator of graft materials or growth factors.

• Journal of Periodontal and Implant Science
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• v.46 no.4
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• pp.244-253
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• 2016

Purpose: The aim of this study was to characterize the healing in the grafted calvarial defects of rats after adjunctive hyperbaric oxygen therapy. Methods: Twenty-eight male Sprague-Dawley rats (body weight, 250-300 g) were randomly divided into two treatment groups: with hyperbaric oxygen therapy (HBO; n=14) and without HBO (NHBO; n=14). Each group was further subdivided according to the bone substitute applied: biphasic calcium phosphate (BCP; n=7) and surface-modified BCP (mBCP; n=7). The mBCP comprised BCP coated with Escherichia-coli-derived recombinant human bone morphogenetic protein-2 (ErhBMP-2) and epigallocatechin-3-gallate (EGCG). Two symmetrical circular defects (6-mm diameter) were created in the right and left parietal bones of each animal. One defect was assigned as a control defect and received no bone substitute, while the other defect was filled with either BCP or mBCP. The animals were allowed to heal for 4 weeks, during which those in the HBO group underwent 5 sessions of HBO. At 4 weeks, the animals were sacrificed, and the defects were harvested for histologic and histomorphometric analysis. Results: Well-maintained space was found in the grafted groups. Woven bone connected to and away from the defect margin was formed. More angiogenesis was found with HBO and EGCG/BMP-2 (P<0.05). None of the defects achieved complete defect closure. Increased new bone formation with HBO or EGCG/BMP-2 was evident in histologic evaluation, but it did not reach statistical significance in histometric analysis. A synergic effect between HBO and EGCG/BMP-2 was not found. Conclusions: Within the limitations of this study, the present findings indicate that adjunctive HBO and EGCG/BMP-2 could be beneficial for new bone formation in rat calvarial defects.

• Archives of Reconstructive Microsurgery
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• v.19 no.1
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• pp.29-36
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• 2010

The purpose of this study was to present the clinical significance of rectus abdominis free muscle flap for large sized diabetic ulcer and necrosis of the foot to salvage limb. From June 2000 to February 2006, eleven patients were included in our study. There were seven males and four females with a mean age of 58.3 years (48~65) at the surgery. All had a history of diabetics and subsequent huge soft tissue defect caused by necrotizing abscess formation around the foot and the ankle. After complete debridement of large sized, infected necrotic tissue, susceptible intravenous antibiotics and wound care were done. After control of infection, confirmed by clinical and laboratory findings, the rectus abdominis free muscle flap was applied to cover remained large soft tissue defect and to prevent the recurrence of infection. All flaps survived and it provided satisfactory coverage for the soft tissue defect on the foot and the ankle area for a mean of 41.1 months (24~85) follow up period. All except of one patients did not have any recurrence of infection on the operation site and could salvage their limbs. The rectus abdominis free muscle flap could be recommended for large sized soft tissue defect after necrotizing abscess in diabetic foot to salvage major limb.

• Journal of Veterinary Clinics
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• v.32 no.4
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• pp.343-346
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• 2015

A 4-year-old castrated male Dachshund was presented with a chronic history of dyspnea and cyanosis. Complete blood count revealed marked polycythemia with a hematocrit of 79.7%. Thoracic radiographs showed mild right-sided cardiac enlargement. Echocardiography showed a large ventricular septal defect in the left ventricular outflow tract region just proximal to the aortic valve. On Doppler echocardiography, right-to-left shunt flow through the defect was found and confirmed by contrast echocardiography. Based on these diagnostic findings and clinical signs, the dog was diagnosed as right-to-left shunting ventricular septal defect. Phlebotomy and oxygen supplement were performed, but the dog died the day after presentation.

• Structural Engineering and Mechanics
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• v.28 no.5
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• pp.525-548
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• 2008

This article deals the theory for solving an inverse problem of plate structures using the frequency-domain information instead of classical time-domain delays or free vibration eigenmodes or eigenvalues. A reduced set of output parameters characterizing the defect is used as a regularization technique to drastically overcome noise problems that appear in imaging techniques. A deconvolution scheme from an undamaged specimen overrides uncertainties about the input signal and other coherent noises. This approach provides the advantage that it is not necessary to visually identify the portion of the signal that contains the information about the defect. The theoretical model for Quantitative nondestructive evaluation, the relationship between the real and ideal models, the finite element method (FEM) for the forward problem, and inverse procedure for detecting the defects are developed. The theoretical formulation is experimentally verified using dynamic responses of a steel plate under impact loading at several points. The signal synthesized by FEM, the residual, and its components are analyzed for different choices of time window. The noise effects are taken into account in the inversion strategy by designing a filter for the cost functional to be minimized. The technique is focused toward a exible and rapid inspection of large areas, by recovering the position of the defect by means of a single accelerometer, overriding experimental calibration, and using a reduced number of impact events.

• Journal of Chest Surgery
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• v.43 no.4
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• pp.409-412
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• 2010

We have experienced five cases of atrial septal defect closure under complete port access using the da Vinci system. We used only six 8∼12 mm ports without thoracotomy or sternotomy for operation.

• Journal of Chest Surgery
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• v.27 no.5
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• pp.353-363
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• 1994

From January 1978 to December 1992, 59 patients of double chambered right ventricle were repaired. Surgical correction consisted of closure of the ventricular septal defect and resection of anomalous muscle bundles through right ventriculotomy [Group I ; 34 patients] or right atriotomy [Group II ; 25 patients]. Between these two groups, there was no difference in the operation time and the postoperative results. All patients survived. In group I, hemodynamically significant residual ventricular septal defect was found in three and reoperations were necessary. In one patient, subacute bacterial endocarditis developed postoperatively. In group II, complete atrioventricular block developed in one and mediastinitis in two. Follow-up period was from 2 to 75 months [mean 17.1 months]. There was no late death. All patients have remained in sinus rhythm except one patient. Careful evaluation of echocardiographic and catheterization data preoperatively and careful examination of the anatomy intraoperatively are necessary so that double chambered right ventricle should not be overlooked, because most ventricular septal defects are now closed through the right atrium. Repair of double chambered right ventricle is also easily performed through the atrial approach. Transatrial repair should be considered as an alternative to the transventricular approach in patients with this congenital heart defect. Successful surgical correction of double chambered right ventricle is expected with excellent long term results.

• Archives of Reconstructive Microsurgery
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• v.14 no.2
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• pp.144-151
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• 2005

Purpose: Disaster as traffic accident, industrial disaster, high voltage electrical bum and flame burn of extremity have a destructive effect because of the involvement of deep structure. Generally, such injury may result in decreased function or loss of limb. In this study the successful use of the combined scapular/parascapular flap as microsurgical transfer to cover extensive defect of electrical and flame bum is reported. Material and Method: Between January 2000 and June 2001, the combined scapular and parascapular flap was used for the coverage of soft tissue defect for 7 patients were admitted to our department with high voltage electrical bum and flame burn. The recipient site were the wrist joint in 2 cases, the forearm in 1 case, the ankle joint in 1 case, the foot dorsum in 1 case, the heel in 1 case. Result: Flap survival was complete in all patients. The result of flap coverage for these deep wound was successful. Conclusion: The advantages of scapular/parascapular combined flap were coverage of the large defect, easy shaping of the flap to fit the required three dimensional configuration around the joint, non hair bearing skin of uniform thickness, minimal donor site morbidity.

• Archives of Craniofacial Surgery
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• v.12 no.1
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• pp.37-42
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• 2011

Purpose: Cancer arising from the external auditory canal is a rare disease. A lesion that seems harmless in someway, can be lethal when inadequately excised, the tumor may infiltrate nerves, the parotid and auditory tissues before re-invading the skin. Wide resection of the lesion surrounding the structure and reconstruction with an adequate plan is crucial for the treatment of this disease. Methods: Two patients with external auditory canal cancer were treated with muscle flaps and skin grafts. Lateral temporal bone resection (LTBR) was performed for complete resection of the cancer. The defect cavity was obliterated with highly vascularized tissue using pedicled sternocleidomastoid muscle, and temporalis muscle individually, combined with full thickness skin graft for covering the skin defect of the ear. Results: Clear resection margin was obtained, and both patients showed disease free survival during the follow up. There was no complications of hematoma, infection, flap loss, or wound problem in both patients. Both patient received radiation therapy, there was no osteoradionecrosis or any other complication related to radiation therapy. Conclusion: Utilizing pedicled muscle flaps for managing defects after wide resection of the external auditory canal cancer is an effective method for managing this difficult disease.

• Clinical Endoscopy
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• v.56 no.4
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• pp.409-422
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• 2023

Endoscopic resection (ER) is widely utilized as a minimally invasive treatment for upper gastrointestinal tumors; however, complications could occur during and after the procedure. Post-ER mucosal defect leads to delayed perforation and bleeding; therefore, endoscopic closure methods (endoscopic hand-suturing, the endoloop and endoclip closure method, and over-the-scope clip method) and tissue shielding methods (polyglycolic acid sheets and fibrin glue) are developed to prevent these complications. During duodenal ER, complete closure of the mucosal defect significantly reduces delayed bleeding and should be performed. An extensive mucosal defect that comprises three-quarters of the circumference in the esophagus, gastric antrum, or cardia is a significant risk factor for post-ER stricture. Steroid therapy is considered the first-line option for the prevention of esophageal stricture, but its efficacy for gastric stricture remains unclear. Methods for the prevention and management of ER-related complications in the esophagus, stomach, and duodenum differ according to the organ; therefore, endoscopists should be familiar with ways of preventing and managing organ-specific complications.