• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.293-299
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• 1999

Bone scintigraphy with $^{99m}Tc-methylene$ diphosphonate(MDP) performed for 20 weeks per two weeks interval respectively after fracture in seven(male 3 heads, female 4 heads) canine radius were analysed. All of bone scans performed 2 weeks to 20 weeks after fracture showed increase in generalized tracer uptake and showed localized increase in tracer uptake at the fracture site. Bone scans and ratio performed 6 weeks after fracture showed the most outstanding increase in generalized and localized tracer uptake. New bone formation had been observed from 2 weeks and they were incorporated completely on 18 weeks, they showed most activity during 6-10 weeks after fracture. It was recognized that the bone scan with $^{99m}Tc-methylene$ was quite sensitivity but low specificity on the fracture healing in canine radius.

• Smart Structures and Systems
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• v.32 no.3
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• pp.167-177
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• 2023

A probabilistic micromechanical framework is proposed to quantify numerically the self-healing capabilities of polymers containing microcapsules. A two-step self-healing process is designed in this study: A probabilistic micromechanical framework based on the ensemble volume-averaging method is derived for the polymers, and a hitting probability model combined with a crack nucleation model is then utilized for encountering microcapsules and microcracks. Using this framework, a series of parametric investigations are performed to examine the influence of various model parameters (e.g., the volume fraction of microcapsules, microcapsule radius, radius ratio of microcracks to microcapsules, microcrack aspect ratio, and scale parameter) on the self-healing capabilities of the polymers. The proposed framework is also implemented into a finite element code to solve the self-healing behavior of tapered double cantilever beam specimens.

• Computers and Concrete
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• v.15 no.1
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• pp.37-54
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• 2015

In general, cracks significantly deteriorate the in-situ performance of concrete members and structures, especially in urban metro tunnels that have been embedded in saturated soft soils. The microcapsule self-healing method is a newly developed healing method for repairing cracked concrete. To investigate the optimal microcapsule parameters that will have the best healing effect in concrete, a 3D analytical probability healing model is proposed; it is based on the microcapsule self-healing method's healing mechanism, and its purpose is to predict the healing efficiency and healing probability of given cracks. The proposed model comprehensively considers the radius and the volume fraction of microcapsules, the expected healing efficiency, the parameters of cracks, the broken ratio and the healing probability. Furthermore, a simplified probability healing model is proposed to facilitate the calculation. Then, a Monte Carlo test is conducted to verify the proposed 3D analytical probability healing model. Finally, the influences of microcapsules' parameters on the healing efficiency and the healing probability of the microcapsule self-healing method are examined in light of the proposed probability model.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.3
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• pp.94-102
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• 2014

Purpose: This study aims to validate the effect of autoclaved autogenous bone (AAB), incorporating Escherichia coli-derived recombinant human bone morphogenetic protein-2 (ErhBMP-2), on critical-sized, segmental radius defects in rabbits. Delivery systems using absorbable collagen sponge (ACS) and fibrin glue (FG) were also evaluated. Methods: Radius defects were made in 12 New Zealand white rabbits. After autoclaving, the resected bone was reinserted and fixed. The animals were classified into three groups: only AAB reinserted (group 1, control), and AAB and ErhBMP-2 inserted using an ACS (group 2) or FG (group 3) as a carrier. Animals were sacrificed six or 12 weeks after surgery. Specimens were evaluated using radiology and histology. Results: Micro-computed tomography images showed the best bony union in group 2 at six and 12 weeks after operation. Quantitative analysis showed all indices except trabecular thickness were the highest in group 2 and the lowest in group 1 at twelve weeks. Histologic results showed the greatest bony union between AAB and radial bone at twelve weeks, indicating the highest degree of engraftment. Conclusion: ErhBMP-2 increases bony healing when applied on AAB graft sites. In addition, the ACS was reconfirmed as a useful delivery system for ErhBMP-2.

• Archives of Plastic Surgery
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• v.35 no.6
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• pp.751-754
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• 2008

Purpose: Delayed rupture of flexor pollicis longus as a sequelae of the plate inserted for distal radius fracture is a very rare. This is the first case reported and published in Korea. Methods: A 48 years old female patient visited hospital, complaining flexor disturbance of interphalangeal joint of left thumb, which suddenly occurred without any external wound. We found that she had received operation of fixing plate for fracture of left distal radius 10 years ago. As operational opinion, we have checked that flexor pollicis longus tendon has been ruptured with oblique ways being stimulated by extended plate to palmar side over long period. Results: Authors performed tenorrhaphy of flexor pollicis longus without tendon graft and presented a successful active flexion of the left thumb interphalangeal joint 1 year after the operation. Conclusion: If the extruded part of the end plate is observed during the operation or follow-up, it is considered to be necessary to get rid of the plate as early as possible after the fracture healing.

• Journal of Veterinary Clinics
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• v.36 no.2
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• pp.93-97
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• 2019

Healing of 48 cases of radial fractures in small breed dogs treated with acrylic pin external fixation was evaluated retrospectively to investigate the factors affecting the healing of radial fractures. The mean age of the subjects was 15.02 months, the mean body weight was 3.48 kg, and the mean maximum length of the radius (MLR) was 90.77 mm. External skeletal fixation frames type 1a, 2a, and 3 were used; among them type 2a was used most frequently (75%). The mean time to clinical union (TCU) was 67.17 days, and the success rate was 95.8%. Age, bodyweight, MLR, and occurrence of complications increased TCU significantly. Among complications, pin loosening, swelling of the operated forelimb tissue for more than 2 weeks, and coexistence of two or more complications increased TCU significantly (p < 0.05). There was no relationship between location of the fracture and TCU. The results of this study may be useful to predict the prognosis of radial fractures in small dogs.

• Journal of Veterinary Clinics
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• v.20 no.3
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• pp.403-405
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• 2003

A 11 month-old Shihtzu was referred to the Veterinary Medical Teaching Hospital, Seoul National University. Clinical signs of this patient were lameness, shortening limb, angular deformity, rotation of foot, subluxaion of elbow joint and restricted range of movement of left forelimb. For the evaluation of the abnormalities of left forelimb, radiographic examination was carried out. Radiographic findings were characteristics of premature closure of distal ulna such as closure of distal ulna growth plate and cranial bowing of radius. With radiographic signs and physical examination, it was diagnosed as premature closure of growth plate of the left forelimb. After osteotomy of the radius and ostectomy of the ulna, radiographic evaluation of limb about angulation of elbow joint was performed every 2-3 weeks for 3 months. In case of premature closure of distal growth plate of ulna, radiography was very useful for diagnositic method of premature closure of distal ulna and monitoring of healing process.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.2
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• pp.120-124
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• 2009

The concept of biostimulation of wounds by low-level laser therapy(LLLT) is attracting considerable attention. Although its effect on whole tissues has been studied quite extensively, the biological and cellular mechanisms underlying LLLT have not been clarified. In an experimental radius fracture in rabbits, Tang and Chai reported that LLLT enhanced the activity of red blood cells, macrophages, fibroblasts, chondrocytes, and osteoclasts within the fracture area. The purpose of the present study was to evaluate the effect of LLLT with a GaAlAs diode laser device on bone healing in rabbit mandibular fractures. We use 12 rabbits for this study. All rabbits were fractured mandible angle area using saw in anesthetic condition. In control group(n=6), none treatment was performed at fracture site. In experimental group(n=6), LLLT with a GaAlAs diode laser was radiated at fracture site daily for 7 days. All rabbits were sacrificed at 6 weeks later from performed fracture day. We studied the immunohistochemical staining of CD34 and Vimentin and the histochemical analysis for calcium and phosphorus content. The results were as follows. 1. In the histological and immunohistological staining, after 6week, fibroblasts, osteogenic cells and collgen fibers were observed more in experimental group than in control group. 2. In the histochemical analysis, the amount of calcium and phosphorus contents of the experimental group were more than the control group. From the results obtained, we suggest that the bone healing is stimulated by low-level laser irradiation in bone fractures.

• Journal of Periodontal and Implant Science
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• v.34 no.3
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• pp.551-562
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• 2004

The purpose of this study was to evaluate the effects of negatively electric field on bone healing in rabbit segmental long bone defects using negatively charged PTFE membrane. Ten millimeter segmental defects in the rabbit radius were used as the experimental model. After membranes were then charge injected using a corona-charging apparatus, the left defects were covered with non charged PTFE membranes as control groups, whereas the right defect was covered with negatively charged PTFE membranes as test group. The animals were divided into 4 groups of 2 rabbits each, and sacrificed at 2, 4, 6, and 8 weeks. Histomorphometric analysis showed a more newly formed bone in negatively charged membrane at early healing period. At 2 weeks, the proportion of new bone formation to total defect area was 0.32% in control group, 1.10% in experimental group. At 4 weeks, the proportion of new bone formation to total defect area was 6.86% in control, and 13.75% in experimental. At 6 and 8 weeks, no obvious difference was found between the two groups but newly formed bone in test groups were slightly more than that in control groups. In conclusion, negatively charged membranes showed more newly bone tissue than noncharged membranes at an early healing period. Although the number of samples was small, this study showed that the combination of negatively electrical stimulation and P1FE membrane may be of value in long bone healing.

• Journal of Veterinary Science
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• v.21 no.4
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• pp.62.1-62.7
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• 2020

A 5-month old Shih Tzu was diagnosed with congenital elbow luxation and uniapical complex angular deformity of the radius. Single radial oblique and dynamic ulnar osteotomies were performed, using patient-specific 3D-printed osteotomy guide. External skeletal fixation was maintained for three weeks to prevent re-luxation of elbow joint. Three months after the surgery, objective gait analysis indicated markedly improved limb function. In addition, radiograph showed improved congruity of elbow joint and appropriate bone healing. In dogs with congenital radial head luxation and concurrent complex angular deformity, a single oblique osteotomy might be a viable option to preserve bone length and correct the luxation of elbow joint.