• 대한두개안면성형외과학회지
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• 제24권1호
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• pp.18-23
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• 2023

Background: When performing reduction of zygomatic arch fractures, locating the inward portion of the fracture can be difficult. Therefore, this study investigated the discrepancy between the locations of the depression on the soft tissue and bone and sought to identify how to determine the inward portion of the fracture on the patient's face. Methods: We conducted a retrospective review of chart with isolated zygomatic arch fractures of type V in the Nam and Jung classification from March 2013 to February 2022. For consistent measurements, a reference point (RP), at the intersection between a vertical line passing through the end point of the root of the ear helix in the patient's side-view photograph and a transverse line passing through the longest horizontal axis of the external meatus opening, was established. We then measured the distance between the RP and the soft tissue depression in a portrait and the bone depression on a computed tomography (CT) scan. The discrepancy between these distances was quantified. Results: Among the patients with isolated zygomatic arch fractures, only those with a fully visible ear on a side-view photograph were included. Twenty-four patients met the inclusion criteria. There were four types of discrepancies in the location of the soft tissue depression compared to the bone depression: type I, forward and upward discrepancy (7.45 and 3.28 mm), type II, backward and upward (4.29 and 4.21 mm), type III, forward and downward (10.06 and 5.15 mm), and type IV, backward and downward (2.61 and 3.27 mm). Conclusion: This study showed that discrepancy between the locations of the depressions on the soft tissue and bone exists in various directions. Therefore, applying the transverse and vertical distances measured from a bone image of the CT scan onto the patient's face at the indicated RP will be helpful for predicting the reduction location.

• Journal of Periodontal and Implant Science
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• 제42권2호
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• pp.50-58
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• 2012

Purpose: This study evaluated histologically the tissue responses to and the effects of a customized nano-hydroxyapatite (n-HA) block bone graft on periodontal regeneration in a one-wall periodontal-defect model. Methods: A customized block bone for filling in the standardized periodontal defect was fabricated from prefabricated n-HA powders and a polymeric sponge. Bilateral $4{\times}{\times}4{\times}5$ mm (buccolingual width${\times}$mesiodistal width${\times}$depth), one-wall, critical-size intrabony periodontal defects were surgically created at the mandibular second and fourth premolars of five Beagle dogs. In each dog, one defect was filled with block-type HA and the other served as a sham-surgery control. The animals were sacrificed following an 8-week healing interval for clinical and histological evaluations. Results: Although the sites that received an n-HA block showed minimal bone formation, the n-HA block was maintained within the defect with its original hexahedral shape. In addition, only a limited inflammatory reaction was observed at sites that received an n-HA block, which might have been due to the high stability of the customized block bone. Conclusions: In the limitation of this study, customized n-HA block could provide a space for periodontal tissue engineering, with minimal inflammation.

• Nuclear Engineering and Technology
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• 제52권10호
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• pp.2410-2414
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• 2020

Heavy ions have a high potential for destroying deep tumors that carry the highest dose at the peak of Bragg. The peak caused by a single-energy carbon beam is too narrow, which requires special measures for improvement. Here, carbon-12 (¹²C) ion with different energies has been used as a source for calculating the dose distribution in the water phantom, soft tissue and bone by the code of Monte Carlobased FLUKA code. By increasing the energy of the initial beam, the amount of absorbed dose at Bragg peak in all three targets decreased, but the trend for this reduction was less severe in bone. While the maximum absorbed dose per bone-mass unit in energy of 200 MeV/u was about 30% less than the maximum absorbed dose per unit mass of water or soft tissue, it was merely 2.4% less than soft tissue in 400 MeV/u. The simulation result showed a good agreement with experimental data at GSI Darmstadt facility of biophysics group by 0.15 cm average accuracy in Bragg peak positioning. From 200 to 400 MeV/u incident energy, the Bragg peak location increased about 18 cm in soft tissue. Correspondingly, the bone and soft tissue revealed a reduction dose ratio by 2.9 and 1.9. Induced neutrons did not contribute more than 1.8% to the total energy deposited in the water phantom. Also during ¹²C ion bombardment, secondary fragments showed 76% and 24% of primary 200 and 400 MeV/u, respectively, were present at the Bragg-peak position. The combined treatment of carbon ions with neutron or electron beams may be more effective in local dose delivery and also treating malignant tumors.

• Archives of Plastic Surgery
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• 제32권4호
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• pp.467-473
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• 2005

Calvarial bone grafting in craniomaxillofacial trauma and facial reconstructive surgery is now widely recognized and accepted as a standard procedure. One of the commonly reported problems of calvarial bone graft is the contour defect caused by partial resorption of the graft. But, there are few reports that discuss the fate of the calvarial bone graft based on the quantitative data. In this article, the changes of grafted calvarial bone were evaluated using 3-dimensional computed tomography(CT). 9 patients were observed with the CT scans at 2mm thickness immediately after operation and at the time of last follow-up. The area of the bone defect was segmented on the 3-dimensional CT image and calculated by AnalyzeDirect 5.0 software. The immediate postoperative bone defect area of the recipient site and the donor site were $612.9mm^2$ and $441.5mm^2$, respectively, which became $1028.1mm^2$ and $268.8mm^2$, respectively at the last follow-up. In conclusion, the bone defect area was less increased on the donor site of calvarial bone graft than on the recipient site. And the CT scan is a valuable imaging method to assess and follow-up the clinical outcome of calvarial bone grafting.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제13권3호
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• pp.265-277
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• 1991

In this study, the healing changes of the implanted bone and its surrounding tissues were examined on the histopathologic basis following implantation of the freeze - dried and radiation - sterilized allogeneic bone in Rectus abdominicus of the rat. This study was performed to see the tissue recations after implantation of the freeze - dried and radiation - sterilized allogeneic bone and whether osteogenesis or osteo - induction or osteo - conduction is happened. And the results were as follows : 1. The shape of the implanted allogeneic bone of the 1, 2 - week group specimen was similar to that of normal bone in light - microscopic finding and the atrophy of cellular organells was found in trans - mission electron - microscopic finding. 2. The implanted allogeneic bone was surrounded with the dense fibroconnective tissues, and infiltration of the chronic inflammatory cells gradually became increased. 3. Hyaline degeneration was observed in the surrounding tissue at the 3, 4, 6 - week group specimen. 4. Light - microscopically the resorption of implanted bone became prominent after 4 - week group and the necrosis of allogeneic bone implant became severe with loss of cell components in lacuna. 5. Electron - microscopically, the osteoclast - like cells ere fond after, 2 - week group. It is summarized that the osteo - conduction potential of the bone is remained just after implanting the freeze - dried and radiation - sterilized allogeneic bone on Rectus abdominicus of the rat, but gradually it disappeared with the gradual increse of chronic inflammatory reaction and osteoclastic activity. So it is suggested that the antigenicity of the freeze - dried and radiation - sterilized bone is remained and it has little osteo - conductive activity when it is implanted in the muscle.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.226.2-226.2
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• 2003

.The healing of a bone defect is complex, and involves a wide range of cellular, molecular, physiological, and biological processes. The main effect of bone substitute is to promote wound healing by induce cell proliferation. Bone defect sites usually are localized below the original bone surface; therefore, space production and maintenance between the membrane and the original bone surface is essential. As a result, membranes must have proper mechanical strength to prevent the collapse of the soft tissue and maintain wound space that permits membranes of poly (L-lactide) (PLLA) were fabricated to provide and maintain sufficient space for bone growth. (omitted)

• Journal of Periodontal and Implant Science
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• 제51권2호
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• pp.100-113
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• 2021

Purpose: Previous studies have solely focused on fresh extraction sockets, whereas in clinical settings, alveolar sockets are commonly associated with chronic inflammation. Because the extent of tissue destruction varies depending on the origin and the severity of inflammation, infected alveolar sockets may display various configurations of their remaining soft and hard tissues following tooth extraction. The aim of this study was to classify infected alveolar sockets and to provide the appropriate treatment approaches. Methods: A proposed classification of extraction sockets with chronic inflammation was developed based upon the morphology of the bone defect and soft tissue at the time of tooth extraction. The prevalence of each type of the suggested classification was determined retrospectively in a cohort of patients who underwent, between 2011 and 2015, immediate bone grafting procedures (ridge preservation/augmentation) after tooth extractions at Seoul National University Dental Hospital. Results: The extraction sockets were classified into 5 types: type I, type II, type III, type IV (A & B), and type V. In this system, the severity of bone and soft tissue breakdown increases from type I to type V, while the reconstruction potential and treatment predictability decrease according to the same sequence of socket types. The retrospective screening of the included extraction sites revealed that most of the sockets assigned to ridge preservation displayed features of type IV (86.87%). Conclusions: The present article classified different types of commonly observed infected sockets based on diverse levels of ridge destruction. Type IV sockets, featuring an advanced breakdown of alveolar bone, appear to be more frequent than the other socket types.

• 대한골관절종양학회지
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• 제9권1호
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• pp.69-76
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• 2003

목적: 족부에 발생하는 종양의 임상적 특성과 병리학적 특성 및 분포 등을 조사하여, 족부 종양을 진단하고 치료하는데 기초 자료를 제공하고자 한다. 대상 및 방법: 족부 종양 환자 141명의 142 종양을 대상으로 하였다. 대상환자들은 모두 조직검사를 통하여 진단이 된 환자들이었다. 대상이 되었던 환자들의 의무기록과 영상 검사들을 후향적으로 검토하여 종양의 역학적 조사와, 임상적 특성과 수술의 방법을 확인하였고, 병리학적 특성을 조사하였다. 종양이 발생 위치는 Kirby 등이 제안한 구역(zone)에 따라 분류하였다. 결과: 여자는 75명이었고 남자는 66명으로 여자가 조금 많았다. 전체 환자들의 평균 나이는 33.2세였다. 양성 연부조직 종양이 68예로 가장 많았고, 양성 골종양이 57예, 악성 연부조직 종양이 12예, 악성 골종양이 5예의 순이었다. 양성 연부조직 종양 중에는 결절종이 36예로 가장 많았고, 양성 골종양 중에서는 조갑하 외골종이 18예, 악성 연부조직 종양 중에서는 편평 상피 세포암이 7예, 악성 골종양으로는 폐암의 전이 병소가 2예였다. 환자들의 임상 증상으로 통증은 악성 골종양 환자들이 가장 높은 비율로 호소하였고, 증상 발현 기간은 양성 연부조직 종양이 가장 길었고, 신경학적 증상은 양성 연부조직 종양에서만 3예가 있었다. 종양의 평균 크기는 악성 골종양이 가장 크고, 양성 골종양이 가장 작았다. 구역별 분포는 전체적으로 5 구역에 59예로 가장 많았고, 4 구역에 10예로 가장 적었으며, 양성 골종양에서는 5 구역, 양성 연부조직 종양에서는 1 구역, 악성 골종양에서는 1, 2 구역, 악성 연부조직 종양에서는 5 구역에서 가장 많았다. 수술 방법으로 병소내 혹은 변연부 절제술, 소파술 혹은 소파술 및 골이식 수술, 족지 절단수술, 슬관절 하 절단술과 사지구제술 등이 있었다. 결론: 족부에 발생하는 종양은 드물고 종류가 다양하면서 대부분(88%) 양성 종양이었으나, 진단 과정에서 환자의 나이, 통증 유무, 증상 발현 기간, 종양의 크기 및 발생 구역 등을 고려하여 악성 종양의 가능성을 배제하지 않음으로써 올바른 치료를 할 수 있을 것으로 사료된다.

• Journal of Periodontal and Implant Science
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• 제34권1호
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• pp.163-175
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• 2004

This study was performed to evaluate bone formation in the calvaria of rabbit by the concept of guided bone regeneration with titanium mesh membrane and demineralized freeze-dried bone. The animal was sacrificed at 2 weeks, 4 weeks, 8 weeks, and 12 weeks after the surgery. Non-decalcified specimens were processed for histologic analysis. 1. The titanium mesh but the biocompatibility was excellent the cell-occlusiveness was feeble. 2. The cell-occlusiveness was feeble and also the soft tissue growth of the upper part of the newly-formed bone after operating was excellent in early stage. 3. The maintenance ability of the space for the GBR very was excellent. 4. The titanium mesh the tissue-integration was superior the wound fixation ability excellent. 5. The demineralized freeze-dried bone did not promote the bone regeneration. 6. With the lapse of time, formation quantity of the bone some it increased, it increased quantity very it was feeble. Within the above results, the titanium mesh for the guided bone regeneration was excellent, the dεmineralized freeze-dried bone confirmed does not promote bone regeneration.

• 대한수의학회지
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• 제48권3호
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• pp.369-374
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• 2008

A neutered male, 8-year-old, Pekingese, weighing 4.3 kg with a history of anorexia, sneezing, nasal discharge, and epistaxis for one month was referred. Soft tissue swelling around the nasal bone and small defects of the hard palate with a tiny round dark red mass were found on physical examination. The laboratory tests represented mild leukocytosis. On skull radiographs, soft tissue swelling and osteolytic change of the incisor bone, nasal bone, and maxilla were found. On computed tomography scan images, there was soft tissue attenuating opacity with calcified spots in the bilateral nasal cavities and frontal sinuses. Loss of nasal turbinate pattern and nasal septum was found. And destruction of the insicor bone, nasal bone, maxilla, hard palate, perpendicular palatine bone, and cribriform plate were identified. Nasal malignant melanoma was confirmed by nasal biopsy.