• Archives of Plastic Surgery
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• 제42권6호
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• pp.677-685
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• 2015

Background The survival rate of grafted fat is difficult to predict, and repeated procedures are frequently required. In this study, the effects of the freezing period of harvested adipose tissue and the addition of human adipose tissue-derived stem cells (ASCs) on the process of fat absorption were studied. Methods Adipose tissue was obtained from patients who underwent a lipoaspirated fat graft. The fat tissue was cryopreserved at $-20^{\circ}C$ in a domestic refrigerator. A total of 40 nude mice were used. The mice in the experimental group received three different subcutaneous injections in the back: an injection of fresh fat and ASCs, an injection of fat that had been frozen for one month and ASCs, and an injection of fat that had been frozen for two months and ASCs. The control mice received fat grafts without ASCs. The mice were sacrificed at four or eight weeks after the procedure, and the grafted fat tissues were harvested. The extracted fat was evaluated using photographic analysis, volume measurements, and histological examination. Results In the control group, the fat resorption rates four weeks after transplantation in the grafts of fresh fat, fat that had been frozen for one month, and fat that had been frozen for two months were 21.14%, 22.46%, and 42.56%, respectively. In the experimental group, the corresponding resorption rates were 6.68%, 13.0%, and 33.9%, respectively. Conclusions ASCs can increase the fat graft survival rate. The use of ASCs in fat grafting can reduce the need for repeated fat grafts and provide good long term results.

• 폴리머
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• 제26권5호
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• pp.680-690
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• 2002

골 재흡수 치료를 목적으로 파미드로네이트를 지속적으로 방출하는 제형으로 제조하기 위하여 락타이드-글리콜라이드 공중합체 (PLGA, 락타이드 : 글리콜라이드 몰비 = 75 : 25, 분자량 20000 g/mole 및 90000 g/mole)를 이용하여 직접압축 성형방법으로 생분해성 웨이퍼를 제조하였다. 약물과 고분자의 함량비 웨이퍼의 두께, PLGA 분자량 등을 조절하여 PLGA 웨이퍼를 제조하였고 이들의 형태학적 특성과 방출거동 및 분해거동을 살펴보았다. 웨이퍼의 제조는 혼합된 분말을 웨이퍼 제작용 몰드에 넣은 후 프레스를 이용하여 일정 압력으로 일정시간 동안 상온에서 가압하여 제조하였다. 제조된 웨이퍼는 약물의 초기함량이 증가할수록 방출속도가 빠르게 나타났으며, 제형의 두께가 두꺼워질수록 시간이 경과함에 따라 약물의 방출속도가 증가하였다. 또한 고분자의 분자량이 큰 것이 작은 것에 비해 상대적으로 초기 약물 방출량이 적고 방출되는 속도 또한 느려져. 저분자보다 오랫동안 약물이 방출되었다. 이러한 약물전달 시스템은 압축성형방법에 의해 제조하므로 제조가 간단하고 약물방출속도를 정확하게 제어할 수 있으므로 이식을 위한 제형으로 제조시 유용하게 쓰일 것으로 예상되었다.

• Journal of Periodontal and Implant Science
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• 제53권2호
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• pp.99-109
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• 2023

Purpose: The aim of this systematic review was to evaluate the effectiveness of the socket shield technique (SST), an innovative surgical method introduced in 2010, for reducing buccal bone plate resorption. Methods: The review was conducted following the PRISMA guidelines. Clinical studies conducted in humans and investigating the SST were searched on PubMed (MEDLINE), Embase, Web of Knowledge, and Google Scholar in November and December 2021. The implant survival rate, percentage of complications, and clinical parameters (marginal bone loss [MBL], pink esthetic score [PES], and buccal bone plate resorption [BBPR]) were analyzed using the collected data. Results: The initial search resulted in 132 articles. After article screening, the full texts of 19 studies were read and 17 articles were finally included in the review. In total, 656 implants were installed with the SST. Nine of the 656 implants experienced failure, resulting in an implant survival rate of 98.6%. The percentage of complications was about 3.81%. The analysis of clinical parameters (MBL, PES, and BBPR), showed favorable results for the SST. The mean MBL in implants placed with the SST was 0.39±0.28 mm versus 1.00±0.55 mm in those placed without the SST. PES had a better outcome in the SST group, with an average of 12.08±1.18 versus 10.77±0.74. BBPR had more favorable results in implants placed with the SST (0.32±0.10 mm) than in implants placed with the standard technique (1.05±0.18 mm). Conclusions: The SST could be considered beneficial for preserving the buccal bone plate. However, since only 7 of the included studies were long-term randomized controlled trials comparing the SST with the standard implant placement technique, the conclusions drawn from this systematic review should be interpreted with caution.

• Journal of Oral Medicine and Pain
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• 제34권1호
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• pp.91-102
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• 2009

2006년 한 해 동안 경북대학교 구강내과에 측두하악장애를 주소로 내원한 전체 환자 중에 파노라마 방사선 사진 상에서 인정될만한 하악과두흡수가 관찰된 환자를 대상으로 측모두부방사선 사진을 촬영하였으며, 측두하악장애의 임상적 평가와 악안면 골격형태를 분석하여 다음과 같은 결론을 얻었다. 1. 임상적 평가 1) 측두하악장애를 주소로 내원한 총 환자 수는 2419명 이었고 그중 224명 약 9.3%가 과두흡수를 나타내었다. 과두흡수가 있는 환자군 중 여자는 183명(81.7%)이고 남자는 41명(18.3%)으로 여자에서 월등히 많이 유발되었다. 환자의 연령은 12세에서 70세에 걸쳐 분포되었으며 평균 연령은 30.6세였다. 연령분포는 10대가 26.3%(59명), 20대가 34.8%(78명), 30대가 13.8%(31명), 40대가 11.2%(25명), 50대가 7.1%(16명), 60대가 6.3%(14명), 그리고 70대가 0.4%(1명)로 나타났다. 2) 과두흡수 부위의 통증을 호소한 경우는 145명, 통증을 호소하지 않은 경우가 79명이었다. 3) 과두흡수 환자 중 이갈이 습관을 53명, 이깨물기 습관은 80명이 호소하였으며, 다른 기타 습관들을 보고한 경우가 204명이었다. 4) 과두흡수 부위의 통증을 호소한 환자의 치료기간은 1개월 미만이 81명으로 전체적으로 치료기간이 짧게 나타났다. 2. 악안면 골격 형태 평가 전체 과두흡수 환자 224명중 18세 이상의 186명(여자 155명, 남자 31명)만이 한국 성인 정상교합자의 측모두부방사선사진 계측연구 결과와 비교하였다. 1) SNA, SNB는 남녀 모두에서 유의한 작은 값을 나타냈고, ANB항목에서는 남자는 평균 3.57 여자는 5.05으로 여자 환자에서 큰 값을 보여 남자에 비해 하악이 더 후퇴되어 있음을 알 수 있다. 2) 남녀 모두 SN-GoMe, FMA의 각도가 과두흡수 환자에서 유의하게 상당히 커져 있음을 보였다. FMA는 남자는 평균 30.44, 여자는 31.69로 여자에서 수직적 성장이 더 크게 나타났다. 3) 총후안면고경(posterior facial height)이 과두흡수 군에서 모두 작은 것이 특징으로 보였으며, 총전안면고경(Anterior facial height)은 과두흡수 환자군에서 남녀 모두 정상군에 비해 차이가 없었다. 저자의 연구에서 얻어진 결과에 의해 하악과두흡수는 정형외과적으로 퇴행성관절염과는 달리 젊은 여성에서 유병률이 높았으며 이는 남성보다 여성에서 수직적 골격 성장 양상으로 인해 하악과두 전방부의 압축응력을 증가시키는 위험요인을 가진 환자에서 발현이 높은 것으로 생각되며 그리고 노년층보다는 젊은 사람에서 이상기능활동으로 인한 부하의 증가 때문이라 생각한다. 하악과두흡수를 보이는 환자들의 치료기간이 대체적으로 짧으며, 나이가 증가함에 따라 내원하는 환자수가 증가하지 않는다는 것은 이 질환이 자기한정적임을 알 수 있고, 생리적 내성 범위 이상의 부하가 가해져 발생한 하악과두의 재형성 과정으로 생각한다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권2호
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• pp.114-120
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• 2007

The augmentation of soft tissue defects is one of the critical problems in the oral and maxillofacial surgery. Various types of graft materials, both autologous and non-autologous, have been used for the augmentation of soft tissue in the facial region. However, it is not easy to choose an ideal material for soft tissue augmentation because each has its advantages and disadvantages. An ideal graft material should meet the following criteria : it should not leave a scar at the area from which it was taken; should have less likelihood of causing infection; should feel natural after implanted; and should be not absorbed. Among the materials meeting these criteria, human dermis and artificial dermis are commonly used for clinical purposes. The present study was aimed to investigate and compare the resorption rate and the histological change following the use of the autologous dermis, the human homogenous dermis $Alloderm^{(R)}$, and the artificial dermis $Terudermis^{(R)}$ to reconstruct the soft tissue defect. Twenty mature rabbits of either sex, weighing about 2 ㎏, were used. Each rabbit was transplanted with the autologous dermis, $Alloderm^{(R)}$, and $Terudermis^{(R)}$ size $1{\times}1-cm$ at the space between the external abdominal oblique muscle and the external abdominal oblique fascia. They were then divided into 4 groups (n=5 each) according to the time elapsed after the surgery: 1, 2, 4, and 8 weeks. The resorption rate was calculated by measuring the volume change before and after the transplantation, and H-E stain was preformed to observe the histological changes. The resorption rate after 8 weeks was 21.5% for the autologous dermis, 16.0% $Alloderm^{(R)}$, and 36.4% $Terudermis^{(R)}$, suggesting that $Alloderm^{(R)}$ is the most stable while $Terudermis^{(R)}$ is the most unstable. In microscopic examinations, the autologous dermis graft was surrounded by inflammatory cells and showed foreign body reactions. The epidermal inclusion cyst was observed in the autologous dermis graft. $Terudermis^{(R)}$ and $Alloderm^{(R)}$ demonstrated neovascularization and the progressive growth of new fibroblast. The results suggest that $Terudermis^{(R)}$ and $Alloderm^{(R)}$ can be availably for substituting the autologous dermis.

• Archives of Plastic Surgery
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• 제35권3호
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• pp.273-278
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• 2008

Purpose: The most widely accepted protocol for alveolar cleft reconstruction is to repair it during the mixed dentition stage. There were lower resorption rate (about 88%) at this stage. However we found some cases that need repeated bone grafting. Therefore we sought to analyze the cause of repeated alveolar bone grafting in connection with other factors. Methods: From January 2000 to January 2006, thirty-nine secondary alveolar bone grafts with iliac crest spongiosa were carried out. In 39 patients, 5 patients who had significant bone graft resorption received repeated alveolar bone graft. In all the cases, the causes of repeated bone grafts were dental root exposure(angulation), and the deficiency of the bony support for lateral incisor or canine eruption. In 3 cases, there was deficiency of the alveolar bone at the cleft side. There was the need of repeated bone grafts for orthodontic treatment in 2 cases and for application of dental implants in 1 case. Results: During the follow-up period, the clinical and radiologic examinations showed that repeated alveolar bone grafts were maintained successfully without any complications. The volume of the repeated bone graft was sufficient for orthodontic treatment and implantation. Conclusion: The essential conditions for successful alveolar bone grafting includes the status of cleft sided teeth, further treatment and planed schedule, as well as canine eruption. Alveolar bone grafting has to be performed with difference of each case in mind.

• Journal of Nutrition and Health
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• 제37권6호
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• pp.423-430
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• 2004

This study was performed to evaluate the effect of red-yeast-rice on bone metabolism in overiectomized (OVX) rats. Forty female Sprague-Dawley rats (body weight 210 $\pm$ 5 g, 9 weeks old age) were divided into two groups. One group were OVX, and the other group received sham operation (SHAM), and received either control diet (20％ casein) or a red-yeast-rice power supplemented diet (0.1％) for 9 weeks. And then each rat group was further divided into control diet (casein 20％) and red-yeast-rice powder supplemented (0.1％) diet group. All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone mineral density (BMD) and bone mineral content (BMC) were measured using PIXImus (GE Lunar Co, Wisconsin, USA) in spine and femur on 5, 9 weeks after feeding. The serum and urine concentrations of Ca and P were determined. Bone formation was measured by serum osteocalcin and alkaline phosphatase (ALP) concentrations. And bone resorption rate was measured by deoxypyridinoline (DPD) crosslinks immunoassay and corrected for creatinine. Serum osteocalcin, growth hormone, IGF-l and calcitonin were analyzed using radioimmunoassay kits. Urinary Ca and P excretion were not significantly different among the groups. Within the OVX group, the red-yeast-rice group had a lower crosslinks value than the casein group. Therefore the red-yeast-rice supplemented groups had a lower bone resorption ratio than the casein group in the ovariectomized rats. And, the red-yeast-rice group had significantly higher IGF-l hormone than casein group in ovariectomized rats. The red-yeast-rice group had higher spine bone mineral content than those of control group within the OVX groups. This study was an important first step in establishing that the observed beneficial effects of red-yeast-rice on bone, and this study also established the need for a study on the long-term effect of this supplement in a human.

• Journal of Periodontal and Implant Science
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• 제49권3호
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• pp.148-157
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• 2019

Purpose: This study aimed to evaluate periodontal and pulpal healing in replanted rat teeth, preserved under different storage conditions, with or without root conditioning using doxycycline. Methods: A total of 40 maxillary first molars extracted from 20 Sprague-Dawley rats were stored for different durations under different conditions (5 minutes in dry storage and 60 minutes in Hank's balanced salt solution [HBSS]) and subsequently replanted. The rats were divided into 2 groups based on the use of root surface treatment: the doxycycline group (root surface treated with doxycycline) and the control group (no doxycycline treatment). Eight weeks after replantation, the animals were sacrificed, and the teeth were evaluated using micro-computed tomography (micro-CT) and histomorphometric analysis. Results: In the micro-CT analysis, the doxycycline group showed the same rate of occurrence of periapical radiolucency as was observed in the control group, but a lower degree of root resorption in teeth replanted after 60 minutes of storage in HBSS (P<0.05). In the histomorphometric analysis, the doxycycline group exhibited no improvement in either pulpal or periodontal healing of the replanted tooth after 5 minutes of dry storage, but showed a lower grade of surface root resorption ($1.37{\pm}0.77$) and inflammatory resorption in the teeth stored for 60 minutes in HBSS ($1.33{\pm}0.71$). Conclusions: In conclusion, doxycycline improved the periodontal healing of replanted teeth stored for 60 minutes in HBSS, whereas doxycycline did not improve periodontal healing of replanted tooth after 5 minutes of dry storage. Within the limits of this study, doxycycline showed more favorable periodontal healing despite delayed replantation.

• 전산구조공학
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• 제8권4호
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• pp.17-23
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• 1995

Based on the present FEM study for negative Poisson's-ratio UHMWPE, the following conclusions seem expected. 1) Negative Poisson's-ratio UHMWPE transfers less stresses to the subchondral or peripheral iliac bone, compared to the conventional UHMWPE with Poission's-ratio. 2) Negative Poisson's-ratio cup reduces stresses in UHMWPE cup itself as well as metal backing, and subchondral bone. 3) The reduction in periacetabular mechanical stresses would significantly reduce the rate of fatigue failure and consequently reduce the incidence of aseptic loosening of the cup due to wear or bone resorption.

• 치과방사선
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• 제22권2호
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• pp.339-348
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• 1992

The purpose of this study was to evaluate the correlationship between histopathologic types of ameloblastoma and their radiographic appearances. The materials for this study consisted of 106 patients diagnosed as ameloblastoma both radiographically and histologically. The obtained results were as follows: 1. The incidence of ameloblastoma in male(60cases, 56.6%) was slightly higher than that in female (46 cases, 43.4%). The average age was estimated as 30.7 years with a range from 6 to 76 years. The second decade revealed the highest rate. 2. 106 ameloblstomas were histopathologically classified as 36 unicystic, 28 plexiform, 20 follicular, 14 acanthomatous, 7 granular cell, and 1 basal cell ameloblastoma. 3. Unilocular, soap-bubble appearance and scalloped margin were the radiographic appearances frequently seen in unicystic ameloblastoma. The predominant radiographic appearance of plexiform ameloblastoma showed unilocular radiolucency with scalloped margin. 4. 19.8%, 21 cases of ameloblastoma in this study showed containing tooth in their tumor mass by radiography. 5. Root resorption occured in 37 cases(34.9%) and tooth displacement in 7 cases(6.6%). Root resorption and tooth displacement occured in same patient were 24 cases(22.6%). 6. Recurrence occured in 21.7% and average year between initial treatment and recurrence were 2 years.