• Journal of Biomedical Engineering Research
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• v.19 no.1
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• pp.53-58
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• 1998

This study examined the distribution of bone mineral density(BMD) and the von Mises stress in the patella. The BMD of eighteen patellae were determined by using quantitative computed tomography and imaging analysis software. It was found that the BMD of the patella varied with location. BMD values were largest at the superior and lateral regions and decreased inferiorly and medially. This distribution appeared to correspond to the organization of trabeculae within the patella. A two-dimensional finite element analysis was performed on each patella. It was also found that the maximum von Mises stress in the patella occurred along the cortical shell on the non-articular surface. The trabecular von Mises stress existed in the posterior region of the patella. These findings demonstrated the potential for finite element studies in vivo. Further, such studies may lead to the development of custom-made, patient-specific patella prostheses.

• The Journal of the Korean bone and joint tumor society
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• v.20 no.1
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• pp.22-26
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• 2014

An intraosseous epidermal cyst is a rare benign cystic lesion. It is thought to result from congenital factors or trauma and can lead to bone destruction because the cyst develops at the soft tissue around the bone. Radiological findings of intraosseous epidermal cysts are a well-defined radiolucent lesion, with cortical expansion. It is important to differentiate an intraosseous epidermal cyst with other disease developed at distal phalanx because its clinical and radiological findings are similar. We report two rare cases of intraosseous epidermal cysts that developed at the distal phalanx.

• Archives of Reconstructive Microsurgery
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• v.10 no.1
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• pp.18-22
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• 2001

Purpose : The purpose of this study was to evaluate stress fracture of vascularized fibular grafts(VFG) by analyzing factors associated with stress fracture and the treatment results. Materials and Methods : From June 1985 to May 1998, 7 patients with stress fractures in the 38 patients with long bone defect who had vascularized fibular graft were evaluated with clinical and radiologic methods including grafted fibular length and hypertrophic index of de Boer. The average age of the patients was 35 years(range, $14{\sim}60$ years). The mean follow-up period was 20 months(range, $16{\sim}32$ months). Results: 7(18.4%) stress fractures occurred in 38 patients. Characteristics of the fractures were (1) all occurred at lower extremity of male patients treated with VFG for long bone defected caused by infected nonunion; (2) all occurred 10 months at the average(range, $4{\sim}17$ months) after VFG; and (3) the length and hypertrophic index of grafted fibula had no influence on the incidence of stress fracture. Union was obtained in 3 patients by conservative treatment. 4 patients obtained union by internal fixation; one at immediately onset of fracture; and three after failure of conservative treatment who had fracture around the knee joint. Conclusion : Stress fracture may occur during the first one year after vascularized fibular graft and more attention must be paid for prevention of it, especially in the cases of infected nonunion. Stress fracture around the knee joint was expected to lead to a good result of early union by operative treatment.

• Journal of Korean Neurosurgical Society
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• v.57 no.1
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• pp.32-35
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• 2015

Objective : The purpose of this study was to analyze the relationship between fracture pattern and the development of acute radiculopathy after osteoporotic lumbar compression fracture. Methods : This study included 59 patients who underwent bone cement augmentation for osteoporotic compression fracture below the L2 level, which can lead to radiculopathic radiating pain. The patients were divided into two groups according to the presence of radiculopathy (group A : back pain only; group B : back pain with newly developed radiating pain). We categorized compression fractures into three types by the position of the fracture line. The incidence of newly developed radiculopathy was examined retrospectively for each compression fracture type. Results : The overall incidence of newly developed leg pain (group B) was 25%, and the frequency increased with descending spinal levels (L2 : 0%, L3 : 22%, L4 : 43%, and L5 : 63%). The back pain-only group (group A) had mostly superior-type fractures. On the other hand, the back pain with radiculopathy group (group B) had mostly inferior-type fractures. Most patients in group B showed significant relief of leg pain as well as back pain after bone cement augmentation. Conclusion : The incidence of a newly developed, radiating pain after osteoporotic compression fractures increased gradually from the L3 to L5 levels. Most of these fractures were of the inferior type, and the bone cement augmentation procedures seemed to be sufficient for relief of both back and radiating pain.

• The Journal of the Korean dental association
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• v.55 no.1
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• pp.30-41
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• 2017

Inadequate keratinized mucosa around dental implants can lead to more plaque accumulation, tissue inflammation, marginal recession and attachment loss. We evaluated the effects of free gingival and extracellular matrix membrane grafts performed to increase the insufficient width of keratinized tissue around dental implants in the posterior mandible. A 47-year-old female patient presented with discomfort due to swelling of the lower right second premolar area. Due to severe destruction of alveolar bone, the tooth was extracted. After 3 months, a guided bone regeneration (GBR) procedure was performed and then a dental implant was placed 6 months later. During the second-stage implant surgery, free gingival grafting was performed to increase the width of the keratinized tissue. After 12 months, a clinical evaluation was performed. A 64-year-old female patient had a missing tooth area of bilateral lower molar region with narrow zone of keratinized gingiva and horizontal alveolar bone loss. Simultaneous implant placement and GBR were performed. Five months after the first-stage implant surgery, a gingival augmentation procedure was performed with an extracellular matrix membrane graft to improve the width of the keratinized tissue in the second-stage implant surgery. After 12 months, a clinical evaluation was performed. In these two clinical cases, 12 months of follow-up, revealed that the increased width of the keratinized tissue and the deepened oral vestibule was well maintained. A patient showed a good oral hygiene status. In conclusion, increased width of keratinized tissue around dental implants could improve oral hygiene and could have positive effects on the long-term stability and survival rate of dental implants. When planning a keratinized tissue augmentation procedure, clinicians should consider patient-reported outcomes.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.997-1004
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• 2005

In bone remodeling imbalances that are caused by increased bone resorption over bone formation lead to adult skeletal diseases. Thus, we have screened various natural products for their ability to regulate the differentiation of osteoclasts to propose candidates for the prevention or treatment of osteoporosis. Scutellaria baicalensis Georgi and Zizyphus Jujuba Miller var. extracts of 140 natural products inhibited the differentiation of RAW264.7 cells into osteoclast, as showed by the reduced number of tartrate resistant acid phosphatase(TRAP)-positive multinucleated cells and decreased TRAP activity.

• The Journal of the Korean dental association
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• v.58 no.2
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• pp.83-92
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• 2020

In the anterior maxillary area, dental implants for tooth replacement are challenging due to the need to satisfy high esthetic level as well as functionality. Immediate implant placement and provisionalization can dramatically reduce the edentulous period, and then fulfill patient's demand for esthetics. The aim of present case report is to demonstrate two cases that successfully restored single tooth with immediate implant placement and provisionalization in the anterior maxillary area. A 47 years old female was scheduled to replace her maxillary right central incisor due to crown-root fracture by trauma. Another 54-year-old female was planned to place dental implant following tooth extraction of maxillary right lateral incisor owing to continuous pus discharge despite repetitive treatments including apicoectomy. In these two cases, surgical and prosthetic procedures progressed in a similar way. After minimal flap elevation, atraumatic tooth extraction was performed. Implant was placed in proper 3-dimensional position and angulation with primary stability. Bone graft or guided bone regeneration for peri-implant bone defect was conducted simultaneously. Provisionalization without occlusal loading was carried out at the same day. Each definitive crown was delivered at 7 and 5 months after the surgery. Two cases have been followed uneventfully for 2 to 5 years of loading time. In conclusion, Immediate implant placement and provisionalization could lead to esthetic outcome for single tooth replacement with dental implant under proper case selection.

• The korean journal of orthodontics
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• v.35 no.2 s.109
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• pp.153-161
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• 2005

Tooth movement facilitated by corticotomy and distraction osteoseresis was discussed. In this study, a portion of cortical bone which can provide resistance to tooth movement in alveolar bone was removed Active bone deposition was thor Possible in the tension side. Teeth moved at such a speedy rate as we could not imagine from conventional orthodontic treatment. which lead to the reduction of the total treatment Period Posterior movement of the canine or molar teeth was possible without any side effects such as anchorage loss, root resorption or Periodontal breakdown.

• The korean journal of orthodontics
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• v.34 no.5 s.106
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• pp.465-472
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• 2004

Tooth movement facilitated by corticotomy and distraction osteogenesis, a new paradigm in orthodontics, was discussed. Molar uprighting was thought to be either difficult or nearly impossible. In this study, a section of cortical bone, which may act as resistance to tooth movement in alveolar bone, was removed. Active bone deposition was also made possible in the tension side This forms the main concept of tooth movement facilitated by corticotomy and distraction osteogenesis. Molars in two cases were uprighted at such a speedy rate as we could not imagine in conventional tooth movement. which lead to reduction of the total treatment period. And molar uprighting was possible without side effects. for example, supraversion oif the tooth or anterior anchorage loss. These were the superior aspects to conventional orthodontics.

• Clinical and Experimental Reproductive Medicine
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• v.48 no.3
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• pp.245-254
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• 2021

Objective: In humans, polycystic ovary syndrome (PCOS) is an androgen-dependent ovarian disorder. Aberrant gene expression in folliculogenesis can arrest the transition of preantral to antral follicles, leading to PCOS. We explored the possible role of altered gene expression in preantral follicles of estradiol valerate (EV) induced polycystic ovaries (PCO) in a mouse model. Methods: Twenty female balb/c mice (8 weeks, 20.0±1.5 g) were grouped into control and PCO groups. PCO was induced by intramuscular EV injection. After 8 weeks, the animals were killed by cervical dislocation. Blood serum (for hormonal assessments using the enzyme-linked immunosorbent assay technique) was aspirated, and ovaries (the right ovary for histological examinations and the left for quantitative real-time polymerase) were dissected. Results: Compared to the control group, the PCO group showed significantly lower values for the mean body weight, number of preantral and antral follicles, serum levels of estradiol, luteinizing hormone, testosterone, and follicle-stimulating hormone, and gene expression of TGFB1, GDF9 and BMPR2 (p<0.05). Serum progesterone levels were significantly higher in the PCO animals than in the control group (p<0.05). No significant between-group differences (p>0.05) were found in BMP6 or BMP15 expression. Conclusion: In animals with EV-induced PCO, the preantral follicles did not develop into antral follicles. In this mouse model, the gene expression of TGFB1, GDF9, and BMPR2 was lower in preantral follicles, which is probably related to the pathologic conditions of PCO. Hypoandrogenism was also detected in this EV-induced murine PCO model.