• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.234-238
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• 1999

This study suggests the design of the functionally gradient composite, [0/90/0/core]$_s$ cross-ply laminate, to prevent stress concentration induced from the difference of rigidity between the bone and the artificial hip joint and to reinforce the wear property of the surface and the expectation of their mechanical properties. First, the four-point bending test is done about wet bones and dry bones to know the mechanical properties of the cortical bones. In result, the wet bone shows the viscoelastic behavior and the dry bone shows the elastic behavior. Moreover, we expect the properties of the proposed gradient composites as a function of carbon fiber volume fraction in each layer to apply Halpin-Tsai equation, CLPT(classical laminate plate theory), and Bernoulli beam theory etc. and decide the thickness ratio of each lamina in order to match Young's modulus of the anisotropic cortical bone with the proposed gradient composites.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06a
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• pp.1064-1069
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• 1994

In order to realize the function of human interface of telecommunications whose objective is to interchange useful information among persons, we developed a bone conduction telephone with which hearing impaired persons with conductive or noise-induced hearing loss and presbycusis can communicate with each other without any other additional devices such as hearing aids. The bone conduction telephone we developed has chatacteristics as follows : (i) a hearing impaired person and a normal hearing person can communicate by bone and air conduction hearings, respectively, using only this telephone set because, as its receiver, it uses a bone conduction vibrator with which we can realize such function with the voice coil and damper of a small speaker unit, the vibrating plate, etc., (ii) it has tone control function compensating hearing losses of hearing impaired persons according to their hearing loss/frequency chatacteristics. Using the tone control function together with a received volume control, it has the received volume range of 20dB in loudness rating; and (iii) it has the function of three emergency calls and a bell lamp as the visual display of a received call.

• Journal of Chest Surgery
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• v.49 no.1
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• pp.1-8
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• 2016

More than a century ago, the first scientific report was published about fracture fixation with plates. During the 1950's, open reduction and plate fixation for fractures were standardized by the founders of Arbeitsgemeinschaft $f{\ddot{u}}r$ osteosynthesefragen/Association for the Study of Internal Fixation. Since the introduction of plate fixation for fractures, several plates and screws have been developed, all with their own characteristics. To accomplice more fracture stability, it was thought the bigger the plate, the better. The counter side was a compromised blood supply of the bone, often resulting in bone necrosis and ultimately delayed or non-union. With the search and development of new materials and techniques for fracture fixation, less invasive procedures have become increasingly popular. This resulted in the minimally invasive plate osteosynthesis (MIPO) technique for fracture fixation. With the MIPO technique, procedures could be performed with smaller incisions and thus with less soft tissue damage and a better preserved blood supply. The last 5 years rib fixation has become increasingly popular, rising evidence has becomeavailable suggesting that surgical rib fixation improves outcome of patients with a flail chest or isolated rib fractures. Many surgical approaches for rib fixation have been described in the old literature, however, most of these techniques are obscure nowadays. Currently mostly large incisions with considerable surgical insult are used to stabilize rib fractures. We think that MIPO deserves a place in the surgical treatment of rib fractures. We present the aspects of diagnosis, preoperative planning and operative techniques in regard to MIPO rib fixation.

• Journal of Veterinary Clinics
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• v.33 no.6
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• pp.385-388
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• 2016

A 2-year-old, castrated male Chihuahua dog was referred for revision surgery for reluxation of the patella following surgery for medial patellar luxation (MPL) of the left stifle joint. On general inspection, the patient showed bilateral hindlimb weight-bearing lameness. On physical examination, bilateral non-reducible MPL was detected through palpation. Radiographs revealed bone deformities of both hindlimbs. Computed tomography (CT) was applied for a three-dimensional (3D) printing bone model to establish an accurate surgical plan. The bone plate was pre-contoured over the 3D-printing bone model after execution of corrective osteotomy and sterilized prior to use in surgery. Corrective osteotomy was performed through a staged, bilateral procedure. The patient showed improvement of limb function following surgery without reluxation of the patella. The use of 3D-printing bone model for accurate surgical planning of corrective osteotomy appears to be effective in increasing the accuracy of surgery. That may lead to successful surgical outcomes.

• Korean Journal of Cleft Lip And Palate
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• v.9 no.2
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• pp.71-78
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• 2006

The case records of 24 patients in Seoul National University Hospital who had bone grafting of 29 alveolar clefts between 2001 and 2004 were examined. Details were recorded of age, sex, preoperative orthodontictreatment, the time of bone grafting, the type of donor site, cleft width, functional load applicationand the success of grafting as established by lowest marginal bone levels. Using this results and review of literature, we concluded that secondary bone graft with iliac bone before canine eruption with root development of 1/2 to 1/3 provide more favorable results and the functional load introduced to the grafted bone lower the resorption rates.

• Journal of Korean Neurosurgical Society
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• v.46 no.3
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• pp.195-198
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• 2009

Objective : Medpor porous polyethylene was used to reconstruct small bone defects (gaps and burr holes) along a craniotomy bone flap. The feasibility and cosmetic results were evaluated. Methods : Medpor Craniotomy Gap Wedges, V and T, were designed. The V implant is a 10 cm-long wedge strip, the cross section of which is an isosceles triangle with a 4 mm-long base, making it suitable for gaps less than 4 mm after trimming. Meanwhile, the Medpor T wedge includes a 10 mm-wide thin plate on the top surface of the Medpor V Wedge, making it suitable for gaps wider than 4 mm and burr holes. Sixty-eight pterional craniotomies and 39 superciliary approaches were performed using the implants, and the operative results were evaluated with respect to the cosmetic results and pain or tenderness related to the cranial flap. Results : The small bone defects were eliminated with less than 10 minutes additional operative time. In a physical examination, there were no considerable cosmetic problems regarding to the cranial bone defects, such as a linear depression or dimple in the forehead, anterior temporal hollow, preauricular depression, and parietal burr hole defect. Plus, no patient suffered from any infectious complications. Conclusion : The Medpor Craniotomy Gap Wedge is technically easy to work with for reconstructing small bone defects, such as the bone gaps and burr holes created by a craniotomy, and produces excellent cosmetic results.

• Korean Journal of Cleft Lip And Palate
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• v.4 no.2
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• pp.69-78
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• 2001

Alveolar cleft exists in 75% of cleft patients, In alveolar cleft patients, alar base is widening, palatal fistular formation, maxillary growth disturbance & tooth loss of adjacent area is raised, Alveolar bone grafting, especially iliac bone grafting, is a general treatment method. As operation timing, bone grafting is classified with primary, early secondary, secondary, & late secondary, Here we report cleft width, marginal bone height, bone resorption rate, grafted shape & bone densities after secondary iliac bone grafting was done in the Dept. of oral and maxillofacial surgery of chonbuk national university hospital. We compared cleft width to bone resorption rate and grafted shape. Also, alveolar bone densities of grafted and contralateral site was compared with Emago 3 package? (Oral Diagonostic System, The Netherlands), The data obtained were analyzed using Spearman's rho coefficients and sign test with SPSS for window, The results were obtained as follows. 1. As alveolar cleft width is increase, bone resorption rate is, too. This relation showed significant difference(P<.01). 2, In proximal & distal area, alvolar cleft width and bone graft contour after bone grafting had a reverse proportional difference. It was not significant difference(P>.05). 3. After 3 month, in bone density results by using Emago 3 package? with periapical standard view, occlusal view & panoramic view, differences between grafted bone and alveolar bone of contralateral site didn't show a significant difference(P>.05). Thus, differences of bone densities in the alveolar bones didn't exist.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.12 no.1
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• pp.193-201
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• 1990

This is a case report of a florid osseous dysplasia occurred in the left posterior region of the mandible in a 60-year-old female. Florid osseous sysplasia is a distinct clincial pathologic entity representing an exuberant variant of osseous dysplasia, defined by Robinson to be a abnormal reaction of bone to irritation or stimulation. The treatment was performed with partial mandibulectomy and immediate reconstruction with metal plate and iliac bone graft. The patient did well postoperatively and has shown no sign of recurrence or complication during the 6 month postoperative period.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.4
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• pp.377-382
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• 1997

Miniplate의 사용은 Champy등의 보고 이후 구강외과 영역에 있어서 외상 혹은 악교정수술등 많은 분야에 이용되기 시작했다. 전통적인 악간고정 방법에 비해 miniplate는 사용하기 쉽고, 정확한 해부학적 정복 및 고정을 가능케 하며 결과적으로 빠른 치유를 가능케 한다는 장점들을 갖고 있다. 그러나 감염, wound dehiscence, 부식, 나사의 헐거워짐, 주위조직의 변색 그리고 stress shielding effect등의 후유증들이 보고되어 왔으며 가장 무해한 금속이라고 알려진 titanium 또한 주위조직 및 lung, spleen, liver 그리고 kidney 등과 같은 조직으로 metal을 전이시키는 것으로 보고되고 있다. 특히 안와골 주변과 같은 상부 연조직이 얇은 곳에 miniplate를 사용할 경우 miniplate가 만져지거나 보일수도 있다는 점이 보고되었으며 따라서 술후 사용되었던 miniplate를 제거 해야만 할 것인가가 또한 주된 관심사로 보고되고 있다. 이에 저자는 이러한 금속성 miniplate의 단점을 개선하고자 자가 두개골을 이용한 플레이트를 고안하였다. '자가 두개골 플레이트'의 적응증은, enophthalmos 개선의 목적으로 두개골을 채취해 임플란트로 사용하는, enophthalmos를 동반한 관골 및 안와골의 복합골절환자에 있어 두개골의 추가채취가 가능한 경우가 될 수 있겠다. 자가 두개골을 이용해 플레이트를 고안하려고 본 증례에서의 시도는 구강외과 영역에 있어서 자가 두개골이 골편이 고정재료로도 쓰일 수 있다는 가능성을 보여주었다는 점에서 의미가 있다고 저자는 생각한다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.3
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• pp.231-233
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• 2002

Temporary reconstruction of the mandibular continuity defect resulting from the ablative tumor surgery with a reconstruction plate can be used for the preservation of normal facial contour and oral function and for periodic follow up of recurrence. Reconstruction plates are adapted to the bone before the resection and provisionally fixated with some screws. Accurate contouring and adaptation are very important for the prevention of displacement of bony stumps and decubituous skin ulcer. However, if there is large expanding buccal tumor mass in mandible, it is very difficult or even impossible to contour the plate before resection. I, therefore, introduce the reconstruction plate application technique using a simple condylar repositioning miniplate after segmental mandibular resection.