• International Journal of Oral Biology
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• 제41권2호
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• pp.83-88
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• 2016

Periodontitis is an inflammatory disease, which destroys the connective tissue and the alveolar bone. Recently, it has been suggested that the effect of natural substances could be induced into an anti-inflammatory environment. However, the effect of Safflower seed extract (SAF-M) associated with periodontitis has not been investigated yet. Therefore, the purpose of this study was to assess the anti-inflammatory effects of SAF-M. Cytotoxicity was assessed through MTS analysis using hGF and hPDL cells. Periodontitis was induced by injecting LPS into gingival tissue on the maxillary molars of rats ($45{\mu}g$ LPS/one time, 3 times a week for 3 weeks). SAF-M was administered daily at 30 mg/kg and 100 mg/kg. Alveolar bone resorption was evaluated through the micro-CT. hGF and hPDL cells showed differential cytotoxicity in response to SAF-M at 5 mg/ml and 1 mg/ml concentrations. Micro-CT showed reduction of the alveolar bone resorption in the SAF-M treatment group. These results suggested that SAF-M is a potential therapeutic agent for periodontitis.

• 대한치과보철학회지
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• 제39권4호
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• pp.376-390
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• 2001

Alveolar bone changes after immediate loading on implants up to one year were observed by means of standard intraoral X-ray measurement which were taken at 3 month intervals. At the same time, bone density changes were observed according to digital subtraction method which is a becoming a more and more promising diagnostic tool for implants. Following results were obtained ; 1. There was no significant difference in the amount of alveolar bone loss implant type, sex and implant diameter, but there was difference according to case selection. In fully bone anchored prostheses cases, bone loss was $1.16{\pm}0.15m$ whereas, in partial edentulous cases, it was $1.84{\pm}0.08mm$. 2. Alveolar bone loss after immediate loading showed a higher degree of bone loss than after submerged loading in the initial three months. But there were no significant difference at the 12th month. 3. According to the one year bone density change observation at the alveolar bone surrounding the implant, significant change was observed vertically, whereas no significant change could observed horizontally. According to the above mentioned results, we can conclude that immediate loading of implants results in a higher degree of alveolar bone loss in one year than submerged loading. But since alveolar bone loss rate decreases to a reasonable rate after the initial 3 months of rapid bone loss, immediate loading of implants seems to be an acceptable treatment modality for patients with good bone conditions. Fully bone anchored cases showed an favorable outcome, but partial edentulous cases showed more bony resorption. So this cases considered in case selections. Bone density changes observation in the study was performed for only one year therefore a more longitudinal observation may be studied.

• 대한치과보철학회지
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• 제44권3호
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• pp.295-313
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• 2006

Statement of problem. Higher fracture rates were reported for Branemark implants placed in the maxilla and for 3.75 mm diameter implants installed in the posterior region. Purpose. The purpose of this study was to investigate the fracture of a fixture by finite element analysis and to compare different diameter of fixtures according to the level of alveolar bone resorption. Material and Methods. The single implant and prosthesis was modeled in accordance with the geometric designs for the 3i implant systems. Models were processed by the software programs HyperMesh and ANSA. Three-dimensional finite element models were developed for; (1) a regular titanium implant 3.75 mm in diameter and 13 mm in length (2) a regular titanium implant 4.0 mm in diameter and 13 mm in length (3) a wide titanium implant 5.0 mm in diameter and 13 mm in length each with a cementation type abutment and titanium alloy screw. The abutment screws were subjected to a tightening torque of 30 Ncm. The amount of preload was hypothesized as 650 N, and round and flat type prostheses were 12 mm in diameter, 9 mm in height were loaded to 600 N. Four loading offset points (0, 2, 4, and 6 mm from the center of the implants) were evaluated. To evaluate fixture fracture by alveolar bone resorption, we investigated the stress distribution of the fixtures according to different alveola. bone loss levels (0, 1.5, 3.5, and 5.0 mm of alveolar bone loss). Using these 12 models (four degrees of bone loss and three implant diameters), the effects of load-ing offset, the effect of alveolar bone resorption and the size of fixtures were evaluated. The PAM-CRASH 2G simulation software was used for analysis of stress. The PAM-VIEW and HyperView programs were used for post processing. Results. The results from our experiment are as follows: 1. Preload maintains implant-abutment joint stability within a limited offset point against occlusal force. 2. Von Mises stress of the implant, abutment screw, abutment, and bone was decreased with in-creasing of the implant diameter. 3. With severe advancing of alveolar bone resorption, fracture of the 3.75 and the 4.0 mm diameter implant was possible. 4. With increasing of bending stress by loading offset, fracture of the abutment screw was possible.

• 대한치과교정학회지
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• 제19권2호
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• pp.37-55
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• 1989

The tissue reactions concerned in alveolar bone remodelling at the pressure zones of rat molar periodontium associated with the application of force (15 gm) to the maxillary first molar teeth of the albino rats were studied by the transmission electron microscopy. Osteoclasts referrable to bone resorption were observed thereafter 3 hour survival period and undermining resorption was generated thenceforth 2 day survival period. Bone resorption, reversal zone and new bone formation were simultaneously observed adjacent to the zone of undermining resorption in the 7 day survival period. Osteoclasts with well developed primary lysosome, ruffled border, clear zone, granules and Golgi apparatus were detected at the zone of the bone resorption, and dark and bright cells adjacent to the osteoclasts as well. Mononuclear cells and perpendicularly arranged collagenous fibers were observed in the reversal zone and, on the other hand, osteoblasts with well developed Golgi apparatus and rough endoplasmic reticulum were detected at the zone of bone formation.

• 대한치과의사협회지
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• 제50권3호
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• pp.126-139
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• 2012

Loss of dentition can lead to not only compromised esthetics and functions of the patient, but also alveolar bone resorption. Bone grafting with prosthetic reconstruction of the gingiva can be selected for the treatment, and it provides many benefits as prosthetic gingival reconstruction does not require a complicated surgical process and is available within a short period of time, with stable clinical results. However, conventional porcelain fused to metal prosthesis has certain limits due to its size, and deformation after several firing procedures. In this clinical report, the author would like to introduce a patient with severe alveolar resorption who was treated with gingiva-shaped zirconia/titanium CAD/CAM implant fixed prosthesis for esthetic and functional rehabilitation. Clinical reports Clinical report 1, 2 : A case of loss of anterior dentition with atrophied alveolar bone. Implant retained zirconia bridge applied with Procera implant bridge system to simulate the gingiva. Upper structure was fabricated with zirconia all ceramic crown. Clinical report 3, 4 : A case of atrophied maxillary alveolus was reconstructed with fixed implant prosthesis, a CAD/CAM designed titanium structure covered wi th resin on its surface. Anterior dentition was reconstructed with zirconia crown. Conclusion and clinical uses. All patients were satisfied with the outcome, and maintained good oral hygiene. Zirconia/titanium implant fixed prosthesis fabricated by CAD/CAM system was highly accurate and showed adequate histological response. No critical failure was seen on the implant fixture and abutment overall. Sites of severe alveolar bone loss can be rehabilitated by implant fixed prosthesis with CAD/CAM system. This type of prosthesis can offer artificial gingival structure and can give more satisfying esthetics and functions, and as a result the patients were able to accept the outcome more fondly, which makes us less than hard to think that it can be a more convenient treatment for the practitioners.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권6호
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• pp.462-465
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• 2012

Horizontal and vertical ridge augmentation with implant placement was performed, using a block type of autogenous tooth bone graft in a 37-year old male patient. This material was very useful for the case of severe alveolar bone resorption of a single tooth. After 13 months, excellent bony healing was obtained and final restoration was performed successfully.

• 대한심미치과학회지
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• 제31권2호
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• pp.40-46
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• 2022

상악전치부는 심미적 회복이 가장 중요한 부위이지만 구치에 비해 좁은 협설측 치조골 폭 및 발치시의 치조골 흡수로 인하여, 그만큼 심미적인 결과를 얻기가 어려운 부위이다. 본 증례 보고를 통해 외상으로 인한 상악전치부의 발치 즉시 임플란트 식립을 통해 치조골 및 연조직 소실을 최소화 하며 심미성을 확보하기 위한 고려 사항에 대해 살펴 보고자 한다.

• 대한치과의사협회지
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• 제54권4호
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• pp.284-295
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• 2016

The aim of this study was to evaluate the effect of Epigallocatechin-3-Gallate (EGCG) on the alveolar bone metabolism in a collagen-induced arthritis (CIA) model in mice to enhance the understanding of rheumatoid arthritis (RA)-associated alveolar bone loss. Following the induction of CIA in animals (mice, n=16), mandibles were retrieved for micro-computed tomography (micro-CT) and isolation of alveolar bone cells (ABCs). In vitro osteogenic potentials of ABCs were evaluated and the mRNA expression of downstream effector genes was assessed. CIA was successfully induced in all animals, and micro-CT data showed that alveolar bone loss was significantly increased in the CIA group while the treatment of EGCG prevented the alveolar bone resorption. Osteogenesis by ABCs was significantly increased in the CIA+EGCG group in vitro. The analysis of mRNA expressions showed that osteoclastogenesis-associated genes were increased in CIA group while bone protecting genes were upregulated in EGCG treated group. The results demonstrate that EGCG downregulated the alveolar bone resorption in a CIA model in mice, and upregulation of bone protecting genes appear to be involved. Further studies are warranted.

• 대한치과교정학회지
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• 제31권3호
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• pp.357-367
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• 2001

당뇨병 흰쥐를 대상으로 치조골의 교체(turnover)와 치아 이동 중 치조골의 흡수와 형성의 활성을 비교 관찰하기 위하여 8주령의 웅성 Sprague-Dawley계 흰쥐를 정상대조군(N), 당뇨군(D), 정상-치아이동군(N-tm), 당뇨-치아이동군(D-tm)으로 나누고, 각 실험군은 치아이동 실험 1일, 3일, 7일, 14일의 소군으로 나누었다. 당뇨병은 치아이동 실험 18일전에 스트렙토조토신(50mg/체중 kg)을 꼬리정맥에 단 회 주사하여 유발하였다. 치아이동은 상악 제1대구치를 초기 교정력 40그램으로 근심 이동시켰다. 상악 제1대구치 주위 치조골을 대상으로 골형성 징후표지로서 치조골 alkaline phosphatase(ALP)와 osteocalcin(OC)을, 골흡수 징후표지로서 acid phosphatase (ACP)와 tartrate-resistant acid phophatase(TRAP)을 정량 분석하였으며, D군과 N군에서는 이들의 혈중 농도를 정량 분석하였다. 1. D군의 혈청 TRAP농도와 혈청 OC농도는 모든 실험 경과군에서 N군보다 감소하였고(p<0.05), 당뇨기간이 길어질수록 더 많이 감소한 것으로 나타났다. 또한 치조골 흡수 징후표지는 감소하는 경향이었으며 골형성 징후표지도 실험기간이 경과함에 따라 더 많이 감소하는 것으로 나타났다. 2. N-tm군의 치조골 ACP농토와 TRAP농도는 N군과 비교하여 1일과 3일군에서 가장 높았으며(p<0.01), 그 이후 감소경향을 나타냈고, 치조골 OC함량은 3일, 7일 14일군에서 N 군보다 높았다(p<0.001). 그러나 D-tm군에서 치조골 ACP와 TRAP농도는 정상 N군에 비하여 1일에는 낮으나 7일, 14일 경과군에서 가장 높았고(p<0.001), 실험 경과에 따라 계속 증가 하였으며(p<0.001), 치조골 ALP와 OC 함량은 3일 경과 후부터 증가하지만 정상 N군과 유의차가 없었다. 3. 당뇨-치아이동군의 치아이동량은 정상-치아이동군보다 많은 것으로 나타났다. 이러한 실험 결과는 당뇨병의 전신 골격과 치조골은 골 흡수 활성이 억제되어 있으며 골형성 활성은 당뇨 지속시간이 길어질수록 더 많이 억제되는 느린 골교체를 하며, 교정력에 의한 치조골 흡수활성이 처음 높아지는 시기는 정상치아이동시보다 늦고 더 오랬 동안 지속되며 치조골 형성활성은 낮고, 치아 이동량은 증가하며 이동중 치아동요도가 증가함을 시사한다.

• 대한치과의사협회지
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• 제50권6호
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• pp.329-338
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• 2012

Introduction: The purpose of this study is to evaluate the clinical results of vertical alveolar ridge augmentation using autogenous block bone graft, especially resorption rate, and outcomes of dental implants placed in the grafted site. Patients and Methods: Medical records and radiographs were reviewed. Twenty-seven patients who have been received the autogenous block bone graft which harvested from chin, ramus, and ilium, and the implant installation on 31 areas(22 maxillas and 9 mandibles) were included. Eight implants were installed simultaneously at the time of bone graft in 4 patients, and 65 implants were installed after 4.9 months(range 2~18 months) of autogenous block bone graft in 23 patients. The resorption amount and rate of augmented bone, and the success and survival rates implants were evaluated. Results: Mean height of the augmented block bone was $5.9{\pm}2.3mm$(range from 2.5 to 13.0 mm). Mean follow-up period after block bone graft was 30.4 months(range from 16 to 55 months). Mean resorption of the augmented block bone was $2.0{\pm}1.5mm$ (range from 0.5 to 7.24 mm). The success and survival rates of the implants were 78.1 % and 98.6%, respectively. Conclusion: This study indicates that the autogenous block bone graft is a useful and stable method for alveolar ridge augmentation for dental implant. And more augmentation is needed to compensate the resorption of the grafted bone.