• Journal of Korean Dental Science
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• 제5권2호
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• pp.77-87
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• 2012

Purpose: This study examined the scanning electron microscopic feature, protein marker expression and osteoinductive activity of demineralized dentin matrix (DDM) from human for nude mice. Materials and Methods: Twenty healthy nude mice, weighing about 20 g were used for study. DDM from Human was prepared and implanted into the dorsal portion of nude mouse. Before implantation, DDM was examined by scanning electron microscopy (SEM). Nude mice were sacrificed at 2 weeks, 4 weeks and 8 weeks after DDM grafting and evaluated histologically by H-E, MT staining. And also immunohistochemistry analysis (ostecalcin, osteopontin) was performed. Result: Dentinal tubules and collagen fibers were observed by SEM of dentin surface of DDM. The DDM induced bone and cartilage independently in soft tissues. And, the histological findings showed bone forming cells like osteoblasts, fibroblasts at 2, 4 and 8 weeks. On immunohistochemistry analysis, osteocalcin and osteopontin positive bone forming cells were observed. Conclusion: This results showed that the DDM from human has osteoinductive ability and is a good alternative to autogenous bone graft materials.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제35권6호
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• pp.353-359
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• 2013

Purpose: Extensive research is actively ongoing for development of an ideal bone substitute that meets the gold standard. Tooth was selected as a donor site for evaluation of potentials in bone substitutes based on its similar chemical compositions to alveolar bone. Previous studies have evaluated inorganic components of autogenous tooth bone graft material (AutoBT) and osteoconductivity. In continuation from the previous studies, the current study was conducted for analysis of organic components and evaluation of osteoinductivity of AutoBT. Methods: Forty-six extracted teeth were collected from actual patients (Korea Tooth Bank, R&D Institute). Extracted teeth were processed into AutoBT and implanted in dorsal subcutaneous muscular tissues of 15 athymic mice. Biopsy samples were harvested at two, five, and eight weeks. The Bradford assay, sodium dodecyl sulphate polyacrylamide gradient gel, and western blotting were performed for investigation of organic contents of AutoBT. Results: Histology analyses showed signs of new bone formation as early as two weeks. Results of the Bradford assay indicated the existence of noncollagenous proteins (NCP). 0.29% (2.89 mg/g) of proteins were extracted by weight in the root portion of AutoBT; 0.02% (0.029 mg/g) and 1.79% (17.93 mg/g) of proteins were measured by weight in crown and block-form of AutoBT, respectively. However, recombinant human bone morphogenetic protein-2 was not observed in AutoBT. Conclusion: Within the limitation of the current study, AutoBT induced new bone formation by NCP embedded in dentin.

• Journal of Korean Dental Science
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• 제5권1호
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• pp.21-28
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• 2012

Purpose: In this study the bone healing ability of autogenous tooth bone graft material as a substitute material was evaluated in a mini-pig cranial defect model through histologic examinations and osteonectin reverse transcription polymerase chain reaction (RT-PCR) quantitative analysis. Materials and Methods: A defect was generated in the cranium of mini-pigs and those without a defect were used as controls. In the experimental group, teeth extracted from the mini-pig were manufactured into autogenous tooth bone graft material and grafted to the defect. The mini-pigs were sacrificed at 4, 8, and 12 weeks to histologically evaluate bone healing ability and observe the osteonectin gene expression pattern with RT-PCR. Result: At 4 weeks, the inside of the bur hole showed fibrosis and there was no sign of bone formation in the control group. On the other hand, bone formation surrounding the tooth powder granule was observed at 4 weeks in the experimental group where the bur hole was filled with tooth powder. Osteonectin gene expression; there was nearly no osteonectin expression in the control group while active osteonectin expression was observed from 4 to 12 weeks in the experimental group. Conclusion: We believe this material will show better results when applied in a clinical setting.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제41권2호
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• pp.109-115
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• 2015

Odontoma is the most common odontogenic benign tumor, and the treatment of choice is generally surgical removal. After excision, bone grafts may be necessary depending on the need for further treatment, or the size and location of the odontoma. Although the osteogenic capacity of a demineralized tooth was verified as early as 1967 by Urist and many other investigators, the cumbersome procedure, including a long demineralization time, may be less than comfortable for clinicians. A modified ultrasonic technology, with periodic negative pressure and temperature control, facilitated rapid and aseptic preparation of demineralized teeth for bone grafts. This approach reduces the demineralization time dramatically (${\leq}80$ minutes), so that the graft material can be prepared chairside on the same day as the extraction. The purpose of this article is to describe two cases of large compound odonotomas used as graft material prepared chairside for enucleation-induced bony defects. These two clinical cases showed favorable wound healing without complications, and good bony support for future dental implants or orthodontic treatment. Finally, this report will suggest the possibility of recycling the benign pathologic hard tissue as an alternative treatment option for conventional bone grafts in clinics.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제42권2호
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• pp.90-98
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• 2016

Objectives: The aim of this study was to compare the osteogenic effects of demineralized dentin matrix (DDM) combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) in rabbit calvarial defects with DDM and anorganic bovine bone (ABB) combined with rhBMP-2. Materials and Methods: Four round defects with 8-mm diameters were created in each rabbit calvaria. Each defect was treated with one of the following: 1) DDM, 2) ABB/rhBMP-2, or 3) DDM/rhBMP-2. The rhBMP-2 was combined with DDM and ABB according to a stepwise dry and dip lyophilizing protocol. Histological and microcomputed tomography (${\mu}CT$) analyses were performed to measure the amount of bone formation and bone volume after 2- and 8-week healing intervals. Results: Upon histological observation at two weeks, the DDM and ABB/rhBMP-2 groups showed osteoconductive bone formation, while the DDM/rhBMP-2 group showed osteoconductive and osteoinductive bone formation. New bone formation was higher in DDM/rhBMP-2, DDM and ABB decreasing order. The amounts of bone formation were very similar at two weeks; however, at eight weeks, the DDM/rhBMP-2 group showed a twofold greater amount of bone formation compared to the DDM and ABB/rhBMP-2 groups. The ${\mu}CT$ analysis showed markedly increased bone volume in the DDM/rhBMP-2 group at eight weeks compared with that of the DDM group. Notably, there was a slight decrease in bone volume in the ABB/rhBMP-2 group at eight weeks. There were no significant differences among the DDM, ABB/rhBMP-2, and DDM/rhBMP-2 groups at two or eight weeks. Conclusion: Within the limitations of this study, DDM appears to be a suitable carrier for rhBMP-2 in orthotopic sites.

• 대한소아치과학회지
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• 제27권4호
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• pp.564-572
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• 2000

치아매복에 의한 미맹출시 치아 매복의 방향과 위치 치근단의 완성정도, 맹출공간의 존재여부, 매복치 주변에 과잉치, 치아종, 낭종 등의 존재여부 등에 따라 발치, 교정적 견인, 외과적 자가이식중 어떤 술식을 시행할 것인지 결정하게 된다. 자가 치아이식은 치아의 위치가 교정력을 가할 수 없는 위치에 존재하거나 치아이동이 제한을 받게 되어 통상적인 치료가 불가능할 경우에 발거에 앞서 고려할 수 있다. 자가치아이식의 예후는 치근의 완성도, 외과적 시술능력 환자의 나이, 근관치료, 고정기간과 형태, 치주인대의 보존, 저장 방법 등에 영향을 받는다. 특히 이식 수여부의 골의 결손이 너무 클 경우 치아의 동요도를 감소시키고 골치유를 빠르게 하기위해 골이식을 고려할 수 있다. 치아 미맹출을 주소로 본원에 내원한 증례들로 상악과 하악의 여러 부위에서 과잉치, 치아종, 이소맹출 등의 다양한 원인요소들이 발견되었다. 자가치아이식전 필요시 공간확보를 행하고, 과잉치 및 치아종의 발거로 인해 골결손이 클 때, 탈회냉동건조골과 자가골 이식을 시행하였다. 치아고정은 $2\sim3$주정도 시행하고 $3\sim4$주 후 방사선적 검사와 임상검사후 근과치료의 필요성을 결정하고 정기적인 검사를 시행한 결과 치근흡수소견 등의 비정상적인 소견은 보이지 않고 정상적인 치유소견을 관찰할 수 있었다.

• Journal of Periodontal and Implant Science
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• 제44권5호
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• pp.216-221
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• 2014

Purpose: This retrospective study compares the amount of bone resorption around implants between an autogenous tooth bone graft (AutoBT) and a synthetic bone graft after a bone-added crestally approached sinus lift with simultaneous implant placements. Methods: In all, 37 patients participated in this study. Seventeen patients were grouped as group I and underwent an AutoBT-added sinus lift using the crestal approach. The remaining 20 patients were grouped as group II and underwent synthetic bone grafting. Both groups received the implant placements simultaneously. Of the 37 participating patients, only 22 patients were included in the final results: Eleven patients of group I and 11 patients of group II. Before the surgery, the distance from the alveolar crest to the sinus floor was measured using panoramic radiography. After the surgery, the distance was measured again from the neck of the implant thread to the most superior border of the added graft materials. Then, the amount of sinus lift was calculated by comparing the two panoramic radiographs. After a year, a panoramic radiograph was taken to calculate the resorption of the bone graft material from the radiograph that was taken after the surgery. The significance of the resorption amount between the two types of graft materials was statistically analyzed. Results: The bone height was increased to an average of 4.89 mm in group I and 6.22 mm in group II. The analysis of panoramic radiographs 1 year after the surgery showed an average bone resorption of 0.76 mm and 0.53 mm, respectively. However, the degree of lifting (P=0.460) and the amount of bone-grafted material resorption (P=0.570) showed no statistically significant difference. Conclusions: Based on this limited study, AutoBT can be considered a good alternative bone graft to a synthetic bone graft in a bone-added sinus lift, when extraction is necessary prior to the surgery.

• Journal of Periodontal and Implant Science
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• 제46권5호
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• pp.291-302
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• 2016

Purpose: The aim of the present study was to evaluate the effectiveness of using a mineralized bone cortical allograft (MBCA), with or without a resorbable collagenous membrane derived from bovine pericardium, on alveolar bone remodeling after immediate implant placement in a dog model. Methods: Six mongrel dogs were included. The test and control sites were randomly selected. Four biradicular premolars were extracted from the mandible. In control sites, implants without an allograft or membrane were placed immediately in the fresh extraction sockets. In the test sites, an MBCA was placed to fill the gap between the bone socket wall and implant, with or without a resorbable collagenous membrane. Specimens were collected after 1 and 3 months. The amount of residual particles and new bone quality were evaluated by histomorphometry. Results: Few residual graft particles were observed to be closely embedded in the new bone without any contact with the implant surface. The allograft combined with a resorbable collagen membrane limited the resorption of the buccal wall in height and width. The histological quality of the new bone was equivalent to that of the original bone. The MBCA improved the quality of new bone formation, with few residual particles observed at 3 months. Conclusions: The preliminary results of this animal study indicate a real benefit in obtaining new bone as well as in enhancing osseointegration due to the high resorbability of cortical allograft particles, in comparison to the results of xenografts or other biomaterials (mineralized or demineralized cancellous allografts) that have been presented in the literature. Furthermore, the use of an MBCA combined with a collagen membrane in extraction and immediate implant placement limited the extent of post-extraction resorption.

• 대한치과의사협회지
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• 제50권9호
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• pp.574-585
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• 2012

Purpose : This study was performed to evaluate the healing response around the root perforation restorative material. Materials and Methods : Four beagle dogs were used for experimental study. Endodontic treatment was performed at four maxillary premolars and artificial perforation was formed at furcation area of pulp chamber. Canal was filled with gutta percha cone and the perforation was sealed with MTA at group 1. At group 2, canal was filled and the perforation was sealed with dentin paste. Tooth paste was fabricated using extracted human teeth. Histologic examination of furcation area was performed 2, 4, 8 and 12 weeks after experiment. Results : New trabecular bone formation was observed around the MTA and tooth paste. Lamellar bone was observed as time is over. There were no inflammatory reaction in both groups. Conclusion : There is a possibility which endodontic filling material can be developed using extracted teeth.

• 대한소아치과학회지
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• 제27권2호
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• pp.344-350
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• 2000

외상으로 인하여 치아가 받는 여러 가지 손상형태 중 치관-치근파절이 나타나는 빈도는 영구치에서 5%, 유치열에서는 2%라고 알려져 왔다. 치조정 하방에 파절선이 존재하고 치수노출을 동반한 치관-치근 파절에서는 크게 두가지의 보존적인 치료방법이 있다. 첫째, 교정력에 의해 정출시키는 방법과 둘째 치조와내에서 교합면 방향으로 재위치시키는 Intra-alveolar transplantation 등이 있다. 외과적 정출법은 1970년대에 소개된 이래로 교정적 정출법의 대안으로 많이 시행되고 있으며 높은 성공률을 가진 술식으로 여겨지고 있다. 본 증례는 외상으로 인해 상악 우측 중철치의 치수노출을 동반한 치관-치근 파절이 발생한 경우로 외과적 정출을 시행하기로 하였으나, 치근단 파절편의 길이가 짧아서 치아를 발거 후 회전시켜 재식하는 방법만으로는 파절선을 치조정 상방으로 위치시킬 수가 없었다. 따라서 치아를 발거한 후 파절편의 지지를 위해 치조와의 치근단부에 탈회냉동건조골을 이식한 후에 치근단 파절편을 노출한 후 suture splint를 시행하였다. 1년 3개월간의 관찰결과, 치조백선이 회복되고 정상적인 동요도를 보였으며, 염증성, 대체성 치근흡수 등과 같은 합병증은 발생되지 않았다.