• 대한치과보철학회지
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• 제32권2호
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• pp.225-233
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• 1994

The restorations of the severely damaged teeth by post core have been increased with the developement of endodontic procedures. But high failure rates of these procedures being reported, various restorative modifications were induced for successful treatments. Cast post-core and prefabricated post with core buildups are choice of treatment. The main causes of failure of the restorations are the fracture of post and core, root fracture, and recurrent caries due to microleakage. Recently, the acid etching technique and the use of dentin bonding agent at tooth surface to reduce the possible microleakage at the tooth-restoration interfaces were introduced. The object of this study was to measure and compare the microleakage by the types and cementation methods of post-core. For this study, forty extracted human anterior teeth were selected for specimen. After cleansing and routine endodontic procedures, anatomic crowns of each specimen were removed at the level of 2mm above the cementoenamel junction. Canals were preparated for post insertion and specimens were divided into four groups randomly. Post-cores were fabricated according to method for each group. Microleakage was measured by length of dye penetration at the tooth-restoration interfaces with measuring microscope at 50 magnification. Oneway ANOVA and t-test were performed for statistical analysis of resulting data. The following results were obtained from this study. 1. There wert significant statistical differences in degree of microleakage between each group (p<0.01). 2. Cast post-core cemented with ZPC (Group I) showed the most severe microleakage pattern$(1.5547{\pm}0.0872mm)$, and cast post-core cemented with adhesive resin cement after tooth surface treatment with dentin bonding agent (Group II) showed the least microleakage $(0.1497{\pm}0.0872mm)$. 3. Group IV revealed less dye penetrations than group III, but no statistical significance was seen between two groups.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제20권2호
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• pp.106-111
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• 1998

The aim of this article was to examine the usefulness of costochondral graft in the temporomandibular joint reconstruction. We performed costochondral grafting in the mandibular reconstruction including condyle replacement in 3 patients, which 2 of ankylosed cases and 1 destructed case. In one case, unexpected fracture of costochondral junction has developed at post-operative 2 months, but, normal mouth opening and facial appearance have been acheived by continuing exercise. These patients showed maximum mouth opening of 35-40 mm and no restriction of lateral side movement. They have been improved esthetics and function. We proposed that the costochondral graft is one of the useful method for functional reconstruction of defected mandibular condyle.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권3호
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• pp.378-387
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• 1996

We performed costochondral grafting in mmandibular reconstruction including condyle replacement in 5 patients which have 4 cases of ameloblastoma, 1 case of resorption of left condyle due to osteomyelitis. We harvested the 6 th costochondral cartilage of unaffected side. No specific complications were appeared with unexpected fracture of costochondral junction and infection of operation site, These patients show 30-45mm at month opening, near normal of affected side, near normal or normal of unaffected side at lateral excursion. Postoperative coureses was uneventful with improved cosmetic and functional results. Our report is indicated that the costochondral graft is satisfactory to reconstruct mandibular defect including condyle replacement, especially in growing patients.

• Journal of Korean Neurosurgical Society
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• 제29권2호
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• pp.255-260
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• 2000

The authors report a posttraumatic syringomyelia in a 30-year-old man who has complained pain, weakness of upper arm and dissociation sensory loss since 2 months before. He was underwent by decompressive laminectomy from T12 to L1, reduction of encroached bony fragments, transpedicular screw fixation from T12 to L2 and posterolateral bony fusion due to burst fracture of L1 at other hospital 3 years ago. Preoperative spinal MRI was highly suggestive of wide-spread, multiseptated syringomyelia from C3 to thoracolumbar junction. We performed wide decompressive laminectomy from T10 to L2 and subarachnoid space reconstrucion composed of microdissection of meningeal fibrosis widely, iatrogenic meningocele formation with lefting the dura mater opened for treatment of spinal-spinal pressure dissociation. Clinical manifestations and radiological findings of the patient were improved after the operation. This technique was thought to be superior to shunting procedures in cases of wide-spread, multiseptated post-traumatic syringomyelia.

• Journal of Korean Neurosurgical Society
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• 제45권3호
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• pp.176-178
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• 2009

Traumatic brainstem hemorrhage after blunt head injury is an uncommon event. The most frequent site of hemorrhage is the midline rostral brainstem. The prognosis of these patients is poor because of its critical location. We experienced a case of traumatic brainstem hemorrhage. A 41-year-old male was presented with drowsy mentality and right hemiparesis after blunt head injury. Plain skull radiographs and brain computerized tomography scans revealed a depressed skull fracture, epidural hematoma, and hemorrhagic contusion in the right parieto-occipital region. But, these findings did not explain the right hemiparesis. T2-weighted magnetic resonance (MR) image of the cervical spine demonstrated a focal hyperintense lesion in the left pontomedullary junction. Brain diffusion-weighted and FLAIR MR images showed a focal hyperintensity in the ventral pontomedullary lesion and it was more prominent in the left side. His mentality and weakness were progressively improved with conservative treatment. We should keep in mind the possibility of brainstem hemorrhage if supratentorial lesions or spinal cord lesions that caused neurological deficits in the head injured patients are unexplainable.

• 산업기술연구
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• 제35권
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• pp.3-8
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• 2015

A study has been made on defects which are formed in manufacturing processes of engine bearing and also on fatigue crack growth behavior in each step of bearing metal manufacturing. After the first step(sinter brass powder on steel plate ; Series A) many voids are made on brass surface and its size is decreased by the second step(rolling process of sintered plate ; Series B). After the third step(re-sintering step of brass powder and rolling ; Series C) the number of voids is decreased and its type shows line. The time of fatigue crack initiation and the growth rate of fatigue crack are in order of Series A, Series B, Series C. These reasons are that void fosters the crack initiation and growth, and residual stress made by rolling process effects on the crack growth rate in Series B, C. In forming and machining processes by use of final bearing metal, crack was observed at internal corner of flange and peeling off was observed at junction between steel and brass. Owing to the above crack and peeling off, it is considered that there is a possibility of fatigue fracture during the application time.

• Journal of Korean Neurosurgical Society
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• 제29권3호
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• pp.379-388
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• 2000

목 적 : 경구적 접근법은 두개 경추이행부의 병소에 대한 유용한 접근방법이나 신경외과 의사에게는 비교적 친숙하지 않은 해부학적 구조물과 뇌척수액 누출로 인한 뇌막염의 위험성으로 인하여 많이 사용되지 않고 있다. 본원 신경외과에서는 다양한 두개 경추이행부의 병변에 대한 경구적 접근법을 시행하였으며, 수술 방법에 따른 결과 및 이의 적응증에 대해 발표하고자 한다. 방 법 : 1996년 9월부터 1999년 4월까지 총 8예의 환자에서 경구적 접근법을 시행하였다. 3명의 환자에서 선천성 기형에 의한 두개저 함입이 있었고, 2명에서는 외상성 치상돌기 골절, 2명에서는 외상성 환축추탈구, 1명에서는 비인두부위 가양성 종양을 동반하였다. 5명의 환자에서 전방 접근법 시행후 후방 골유합술을 시행하였다. 결 과 : 환자 전 예에서 양호한 결과를 보였으며 수술전 사지의 부진마비가 있었던 환자에서는 시간이 경과 함에 따라 신경학적 호전을 보였으며, 골유합술을 시행하였던 5예에서 성공적인 골유합이 관찰되었고, 연구개를 절개하였던 환자 4명중 1명이 창상 열개를 보여 재수술로 상처 치유가 가능하였다. 뇌척수액 누수는 한 예에서도 발생하지 않았다. 결 론 : 경구적 접근법은 두개 경추 이행부의 병소에 대한 유용한 접근법으로 사용될 수 있을 것으로 생각된다.

• 대한관절경학회지
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• 제16권1호
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• pp.9-16
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• 2012

목적: 경골 고평부 골절은 슬관절에 다양한 문제를 발생시킨다. 본 연구는 관절경하 경골 고평부 골절에서 반월상 연골 손상 양상을 확인하고자 한다. 대상 및 방법: 2007년 3월부터 2010년 3월까지 경골 고평부 골절을 진단 받은 39명의 환자 중 33명 환자를 대상으로 골절 고정 시내 관절경을 시행하였다. Schatzker 분류에 따르면 1명의 I형(3.3%), 19명의 II형(53.3%), 4명의 III형(13.3%), 2명의 IV형(6.6%), 2명의 V형(6.6%), 5명의 VI형(20%) 소견을 보였다. 결과: 25명의 환자(75.8%)에서 외측 반월상 연골 파열 소견을 보였다. Schatzker II형 환자 19명 중 18명의 환자(94.7%)가, Schatzker III형 환자 4명 중 3명의 환자(75%)가, Schatzker VI형 환자 5명 중 4명의 환자(80%)가 반월상 연골 파열 소견을 보였다. 반월상 연골 중 가장 많이 손상된 부분은 외측 연골의 전각부분이다(22/25). 25명의 반월상 연골 파열 환자 중, 한 명을 제외한 모든 환자에서 반월상 연골 변연부 수직 종파열 양상을 보였으며, 이는 대부분의 경우에 있어 관절경하 봉합술을 시도할 수 있었다. 결론: 경골 고평부 골절에 있어 관절경하 반월상 연골 손상에 대한 파악 및 치료에 유용하며, 경골 고평부 골절환자에서 관절경을 권한다.

• Journal of Korean Neurosurgical Society
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• 제64권3호
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• pp.437-446
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• 2021

Objective : To investigate the radiographic characteristics of the uppermost instrumented vertebrae (UIV) and UIV+1 compression fractures that are predictive of revision surgery following long-segment spinal fixation. Methods : A total 27 patients who presented newly developed compression fracture at UIV, UIV+1 after long segment spinal fixation (minimum 5 vertebral bodies, lowest instrumented vertebra of L5 or distal) were reviewed retrospectively. Patients were divided into two groups according to following management : revisional surgery (group A, n=13) and conservative care (group B, n=14). Pre- and postoperative images, and images taken shortly before and after the occurrence of fracture were evaluated for radiologic characteristics Results : Despite similar degrees of surgical correction of deformity, the fate of the two groups with proximal junctional compression fractures differed. Immediately after the fracture, the decrement of adjacent disc height in group A (32.3±7.6 mm to 23.7±8.4 mm, Δ=8.5±6.9 mm) was greater than group B (31.0±13.9 mm to 30.1±15.5 mm, Δ=0.9±2.9 mm, p=0.003). Pre-operative magnetic resonance imaging indicated that group A patients have a higher grade of disc degeneration adjacent to fractured vertebrae compared to group B (modified Pfirrmann grade, group A : 6.10±0.99, group B : 4.08±0.90, p=0.004). Binary logistic regression analysis indicated that decrement of disc height was the only associated risk factor for future revision surgery (odds ratio, 1.891; 95% confidence interval, 1.121-3.190; p=0.017). Conclusion : Proximal junctional vertebral compression fractures with greater early-stage decrement of adjacent disc height were associated with increased risk of future neurological deterioration and necessity of revision. The condition of adjacent disc degeneration should be considered regarding severity and revision rate of proximal junctional kyphosis/proximal junction failures.

• 대한족부족관절학회지
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• 제7권1호
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• pp.13-20
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• 2003

Purpose: We analysis the outcome and complications of treatment of lesser toe brachymetatarsia. Materials and Methods: We analysed 28 patients 35 cases of lesser toe brachymetatarsia. Mean post operative follow up period was 2 years 8 months. All of the patients were female and mean age at operation was 21 years old. 2 cases of third metatasal bone and 33 cases of fourth metatarsal bone were operated. 8 metatarsal bones were treated using one staged lengthening with tricortical bone graft and 27 metatarsal bones were treated using callotasis with monofixator. Results: The average amount of lengthening was 13.3mm(12mm-15mm) in one staged lengthening, while 14.4mm(4mm-23mm) in callotasis. Average percentile increase was 28.9%(26%-34%) in one staged lengthening and 32%(18%-46%) in callotasis. The average healing index of callotasis was 76 days/cm (41 days/cm-166 days/cm). Satisfied outcomes in 4 cases of 8 cases (50%) after one staged lengthening and 17 cases of 27 cases (63%) after callotasis. 6 complications in 4 cases were occurred after one staged lengthening; insufficient length gain in 3 cases, fracture on the junction of graft bone and metatarsal bone in 1 case, plantar bowing deformity in 1 case and bony fusion of metatarsophalangeal joint in 1 case. 17 complications in 10 patients were occurred after callotasis ; metatarsophalangeal joint stiffness in 8 cases, metatarsophalangeal joint subluxation in 2 cases, overlengthened metatarsal bone in 2 cases, tapering of callus in 1 case, fracture of callus in 1 case, premature consolidation of callus in 1 case, osteomyelitis of metataral head in 1 case and plantar bowing deformity in 1 case. Conclusion: Although one staged lengthening and gradual lengthening using callotasis are effective treatment for lesser toe brachymetatarsia, complications not rarely occured after lengthening. Insufficient lengthening are most common complication after one staged lengthening while metatarsophalangeal joint stiffness lire most common complication after callotasis.