• Journal of Biomedical Engineering Research
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• v.18 no.2
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• pp.107-112
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• 1997

The effect of gamma-irradiation sterilization on molecular structural changes in orthopaedic surgical-grade polyethylene was studied. The relative crystallinity ud. percent crosslinking of the substance increased as a result of the gamma irradiation and varied anisotropically as a function of depth. Samples from the articulating surfaces showed 5% Venter relative crystallinity than those from the mid-sections, whereas samples from the mid-sections exhibited 15% greater crosslinking than those from the surfaces. These anisotropic variations are discussed in assDciation with oxidation.

• Journal of Korean Dental Science
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• v.12 no.2
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• pp.48-57
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• 2019

Purpose: To investigate whether there are specific surgical or clinical conditions where the use of autogenous bone (AB) is superior to the use of bone substitutes (BSs) for maxillary sinus floor augmentation (MSFA). Materials and Methods: We retrospectively analyzed 386 implants after MSFA in 178 patients. The implants were divided into five groups according to the sinus graft material used. Risk factors for implant failure in MSFA, and correlation between residual bone height (RBH) and graft materials in terms of implant survival were investigated. To investigate risk factors for implant failure in MSFA, implant survival according to graft materials, patients' sex/age, surgical site, RBH, healing period prior to prosthetic loading, staged- or simultaneous implantation with MSFA, the crown-to-implant ratio, prosthetic type, implant diameter, and opposite dentition were evaluated. Result: The cumulative 2- and 5-year survival rates of implants placed in the grafted sinus (independent of the graft material used) were 98.7% and 97.3%, respectively. None of the investigated variables were identified as significant risk factors for implant failure. There was also no statistical significance in implant survival between graft materials. Conclusion: There were no specific surgical conditions in which AB was superior to BSs in terms of implant survival after MSFA.

• Archives of Craniofacial Surgery
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• v.11 no.2
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• pp.77-84
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• 2010

Purpose: The nasal bones are the most common fracture sites of the facial bones, and a careful reduction may still result in secondary deformities, such as saddle nose, deviated nose, hump nose etc, requiring secondary cosmetic rhinoplasty. Therefore, this study examined the clinical characteristics of nasal bone fractures to propose guidelines for patient selection and surgical procedures to achieve more satisfactory results and to prevent secondary deformities with simultaneous augmentation rhinoplasty and bony reduction. Methods: The study was based on 26 out of 149 nasal bone fracture patients who underwent simultaneous augmentation rhinoplasty with bony reduction between May 2008 and April 2009. Retrospective analysis was performed according to the clinical data, surgical techniques and postoperative results. Results: Of the 26 patients, there were 15 males and 11 females. The incidence according to the Stranc's classification revealed that 62% of patients were injured by a frontal impact and 38% by a lateral impact. Frontal impact plane I (50%) was the most frequent type. At the follow up, 18 (81.2%) out of 22 patients were satisfied with their postoperative outcome, and the remaining 4 patients were fair. No one was dissatisfied. However, 5 cases in 3 patients (23%) had some complications; minimal implant deviation in 2 cases, minor irregularity on the nasal dorsum in 2 cases and palpable implant movement under palpation in 1 case. None of these cases required surgical correction. Conclusion: With the proper guidance, simultaneous augmentation rhinoplasty with bony reduction can prevent secondary deformities and satisfy the cosmetic outcomes.

• Journal of Korean Foot and Ankle Society
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• v.11 no.2
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• pp.192-197
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• 2007

Purpose: The purpose of this study is to present our clinical results after surgical treatment in tarsal tunnel syndrome due to space occupying lesions. Material and Methods: We performed surgical decompression for tarsal tunnel syndrome in 20 patients from July 2004 to February 2007. Out of them, thirteen cases were due to space occupying lesions around the tarsal tunnel. The average age at operation was 51.3 years old and the duration from symptom onset to surgery was 16.5 months. The operation included removal of space occupying lesions and tarsal tunnel decompression. The clinical parameters were pain visual analogue scale (VAS), AOFAS scale, and subjective satisfaction. Results: The ganglion cysts were the most frequent causes (ten cases) and synovial chondromatosis in 1 case, neurofibroma in 1 case, talocalcaneal coalition in 1 case. The average follow-up duration was 14.5 months. The AOFAS scale showed significant improvement from 77.8 to 92.7. The average VAS decreased from 6.4 to 2.2. Seven out of thirteen patients were satisfied with the results. The excellent results were shown in six patients, the good results in one patient, the fair result in three patients and the unsatisfactory results in three patients. Conclusion: Favorable results could be obtained in patients with known etiology. But not all cases with surgical decompression of space occupying lesions showed satisfactory results. We assume that the clinical results were related to the multiple factors, not only well performed surgery but also age, size lesions and duration of symptoms, ect.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.25 no.4
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• pp.371-374
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• 1999

The treatment of adults with dentofacial deformities is frequently complicated by existence of discrepancies in transverse dimension. Control of the transverse dimension through surgical technique is now a valuable treatment consideration in non-growing patients. Proper diagnosis of relative and absolute maxillary transverse deficiency is imperative prior to surgical intervention. Therapeutic purpose should be implemented accordingly to facilitate correction of transverse discrepancies concomitant with treatment objectives in sagittal dimension in order to provide the patient with the most stable and functional result possible. Concomitant surgical correction of narrow palate require less treatment time, treatment cost and post-treatment relapse is less than to do only orthodontic therapy. This report is concerned with rapid palatal expansion by a combination of corticotomy and orthodontic treatment.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.4
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• pp.299-306
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• 2017

In this case report, immediate loading of an implant-supported single-tooth prosthesis through complete digital workflow. A patient presented for restoration of missing a single tooth in the mandibular first molar. The digital impression was made with intraoral scanner and implant was placed using surgical guide pre-fabricated with pre-operative computed tomography (CT) and scan data. After 1 week later, prefabricated customized abutment and provisional restoration were connected for immediate loading. After 8 weeks later, abutment level impression was taken by intraoral scanner. At 3 months later from implant installation, monolithic zirconia crown were fabricated. This clinical report presents satisfying result in accuracy and patient satisfaction. A completely modeless digital procedure met expectations regarding precision, esthetics, and functionality.

• Journal of Chest Surgery
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• v.25 no.4
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• pp.438-444
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• 1992

We analysed 7,180 annual cases of surgical treatment performed by Department of Thoracic and Cardiovascular Surgery of 6 major institutes in Seoul Korea, All cases were applied to 101 of 140 coded items applicable to the field of Thoracic and Cardiovascular Surgery, in the book of "Standard Price List for Medical Service" which was notified by the Ministry of Health and Social Affairs, and of them, applied field specific items were 70 of 93 applicables. The most frequently applied items were those associated to ECC[extracorporeal circulation] 1,510 cases, and then item of closed thoracostomy 751 cases was next. Except the items associated to ECC, the coded item of the highest "Total cost[fee x total applied numbers]" was mitral valve replacement 182,356,570 won[534,770 won x 341 cases]. 140 items were arranged in "Total cost" order, and then categorized into 5 groups. Medical insurance fees of each group were modified by different grades without changes in sum of total fees. Fees of Group 1, the highest group in "Total cost" were pulled up, on the other hand, Group 4, the lowest group, were pulled down, Group 5, composed of overlapping items with other fields, were not changed. The result of adjustment by grouping showed 21.2% increment effect[535,749,105 won] in real income. And we found that new coded items for modern high technological procedures should be added to "Standard Price List for Medical Service “Standard Price List for Medical Service".

• Journal of Korean Neurosurgical Society
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• v.29 no.11
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• pp.1445-1450
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• 2000

Objectives : The Objective of this study was to analyze the prognostic factors affecting survival in the patients with glioblastomas. Methods : We retrospectively studied 55 consecutive patients with glioblastomas who were admitted to neurosurgery department from January 1988 to March 1998. Fifteen pateients were excluded from the analysis because of follow-up loss and surgical motality. There were 24 male and 16 female patients, with a mean age of 51 years. Surgery consisted of biopsy in 4(10.0%) patients, subtotal resection in 9(22.5%) patients and gross total resection in 27(67.5%) patients. Nine(22.5%) patients received second operation. Twenty-eight(70%) received postoperative radiation therapy. Various levels of radiation dose were used, 6,000 rad over 7 weeks in most cases. The variable factors were examined for their relationship with survival ; age at the time of diagnosis, gender, duration of neurological symptoms, preoperative neurological state(Karnofsky performance score), extent of surgical resection, location of tumor, reoperation, and postoperative radiotherapy and chemotherapy. Result : The mean survival time was 55 weeks, three(7.5%) of the 40 patients survived more than two years. Survival time with biopsy only cases was 24 weeks, for those with subtotal resection 43 weeks, and for those with gross total resection 67 weeks. A mean survival time from the time of reoperation was 42 weeks. Statistically significant survival factors in glioblastoma were extent of surgical resection, postoperative radiotherapy and reoperation. Summary : Results of our series support the views that the extent of surgery, reoperation and postoperative radiation are important prognostic factors. We also recommend radical tumor removal, postoperative radiotherapy and reoperation, if possible.

• Journal of Korean Neurosurgical Society
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• v.50 no.6
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• pp.492-496
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• 2011

Objective : Direct revascularization surgery is regarded as the most effective method of treatment of adults with moyamoya disease. These patients, however, have a higher risk of perioperative ischemic complications than do patients with atherosclerotic stroke, and are at risk for ischemic complications in the hemisphere contralateral to the one operated on. We investigated the incidence and risk factors for ischemic stroke in the contralateral hemisphere after surgical treatment of adults with moyamoya disease. Methods : We retrospectively reviewed the medical records and results of neuroimaging studies on 79 hemispheres of 73 consecutive patients with adult moyamoya disease ($mean{\pm}SD$ age, $37.96{\pm}11.27$ years; range, 18-62 years) who underwent direct bypass surgery over 6 years. Results : Ischemic complications occurred in 4 of 79 (5.1%) contralateral hemispheres, one with Suzuki stage 3 and three with Suzuki stage 4. Three patients showed posterior cerebral artery (PCA) involvement by moyamoya vessels. Advanced stage of moyamoya disease (Suzuki stages 4/5/6; $p$=0.001), PCA involvement ($p$=0.001) and postoperative hypotension (mean arterial blood pressure <80% of preoperative mean arterial blood pressure) on the first ($p$<0.0001) and second ($p$=0.003) days after surgery were significantly correlated with postoperative contralateral ischemic complications. Conclusion : In patients with advanced moyamoya disease and involvement of the PCA, intentional hypotension can result in ischemic stroke in the hemisphere contralateral to the one operated on. Careful control of perioperative blood pressure is crucial for good surgical results.

• Journal of Yeungnam Medical Science
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• v.5 no.1
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• pp.127-133
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• 1988

Two patients, sought treatment for chief complaints of protruding frontal tooth and desired treatment to reduce the prominance of lips, were diagnosed as bimaxillary protrusion via clinical and cephalometric analysis. The authors corrected them by combined surgical and orthodonic treatment. As pre-surgical survey, paper and cast surgery were performed and wafer and resin sprint were constructed. We performed anterior maxillary and mandibular osteotomies in first premolar site to retract the maxillary and mandibular dentoalveolar segment in order to ; 1) decrease prominance of upper and lower lips. 2) create proper lower incisor intrusion. By use of intrtamaxillary fixation, prompt oral intake was possible. We made good result of esthetic improvement and there was no evidence of relapse and any complication.