• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.3
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• pp.103-110
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• 2014

Purpose: The current gold standard for clinical jawbone formation involves autogenous bone as a graft material. In addition, demineralized dentin can be an effective graft material. Although demineralized dentin readily induces heterotopic bone formation, conventional decalcification takes three to five days, so, immediate bone grafting after extraction is impossible. This study evaluated the effect of vacuum ultrasonic power on the demineralization and processing of autogenous tooth material and documented the clinical results of rapidly processed autogenous demineralized dentin (ADD) in an alveolar defects patient. Methods: The method involves the demineralization of extracted teeth with detached soft tissues and pulp in 0.6 N HCl for 90 minutes using a heat controlled vacuum-ultrasonic accelerator. The characteristics of processed teeth were evaluated by scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). Bone grafting using ADD was performed for narrow ridges augmentation in the mandibular area. Results: The new processing method was completed within two hours regardless of form (powder or block). EDS and SEM uniformly demineralized autotooth biomaterial. After six months, bone remodeling was observed in augmented sites and histological examination showed that ADD particles were well united with new bone. No unusual complications were encountered. Conclusion: This study demonstrates the possibility of preparing autogenous tooth graft materials within two hours, allowing immediate one-day grafting after extraction.

• Journal of Periodontal and Implant Science
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• v.39 no.3
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• pp.321-329
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• 2009

Purpose: The purpose of this study was to evaluate the bone regeneration of particulated hydroxyapatite(HA) and block type of hydroxyapatite graft in rabbit calvarial defects. Methods: An 8 mm calvarial circular defects were created in sixteen young adult New Zealand white male rabbits (weight $3.0{\sim}3.5kg$). Each defects were filled with Bio-Oss, particulated HA and block type HA. Sham surgery control defects were filled with blood clots. The specimens were harvested at 4 weeks and 8 weeks for histologic and histomorphometric evaluation. Results: Histomorphometric analysis demonstrated statistical differences in defect closure, new bone formation, and bone density of the four groups. Block type of HA group showed increased bone formation and bone density at 4 weeks and 8 weeks compared with Bio-Oss group or sham surgery control group(p<0.05). Conclusions: Block type of HA is an effective material for osteoconduction in rabbit calvarial defects, which may acts as a guide in use of these products in human application.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.5
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• pp.427-433
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• 2010

Purpose: The objective of this study was to evaluate the efficacy of the subperiosteal tunneling technique with iliac block bone graft for bone augmentation in an edentulous alveolar ridge. Patients and Methods: Total of 8 sites in 7 patients were included in this study. The bone height was evaluated by CBCT preoperatively and 4 months after operation. Total of 11 implants were inserted and evaluated clinically and radiographically. Results: Mean value of the increased bone height was 6.29 mm and no implant failure was observed. There were no complications such as soft tissue dehiscence, exposure of the grafted bone and infection. Conclusion: We have achieved excellent clinical outcomes by this technique, so we concluded that it is useful for augmentation of severely deficient alveolar ridge.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.2
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• pp.145-155
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• 2007

The advent of osseointegration and advances in biomaterials and techniques have contributed to increased application of dental implants in the restoration of maxillary partial edentulous patients. Often, in these patients, soft and hard tissue defects result from a variety of causes, such as infection, trauma, and tooth loss. These create an anatomically less favorable foundation for ideal implant placement. Reconstruction of the atrophic maxillary alveolar bone through a variety of regenerative surgical procedures has become predictable; it may be necessary prior to implant placement or simultaneously at the time of implant surgery to provide a restoration with a good long-term prognosis. Regenerative procedures are used for horizontal and vertical ridge augmentation. Many different techniques exist for effective bone augmentation. The approach is largely dependent on the extent of the defect and specific procedures to be performed for the implant reconstruction. It is most appropriate to use an evidenced-based approach when a treatment plan is being developed for bone augmentation cases. The cases presented in this article clinically demonstrate the efficacy of using a autogenous block graft, guided bone regeneration, ridge split, immediated implant placement technique on the atrophic maxillary area.

• Journal of Periodontal and Implant Science
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• v.45 no.2
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• pp.46-55
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• 2015

Purpose: This study evaluated the mechanical and structural properties of biphasic calcium phosphate (BCP) blocks processed using a modified extrusion method, and assessed their in vivo effectiveness using a rabbit calvarial defect model. Methods: BCP blocks with three distinct ratios of hydroxyapatite (HA):tricalcium phosphate (TCP) were produced using a modified extrusion method:HA8 (8%:92%), HA48 (48%:52%), and HA80 (80%:20%). The blocks were examined using scanning electron microscopy, X-ray diffractometry, and a universal test machine. Four circular defects 8 mm in diameter were made in 12 rabbits. One defect in each animal served as a control, and the other three defects received the BCP blocks. The rabbits were sacrificed at either two weeks (n=6) or eight weeks (n=6) postoperatively. Results: The pore size, porosity, and compressive strength of the three types of bone block were $140-170{\mu}m$, >70%, and 4-9 MPa, respectively. Histologic and histomorphometric observations revealed that the augmented space was well maintained, but limited bone formation was observed around the defect base and defect margins. No significant differences were found in the amount of new bone formation, graft material resorption, or bone infiltration among the three types of BCP block at either of the postoperative healing points. Conclusions: Block bone substitutes with three distinct compositions (i.e., HA:TCP ratios) processed by a modified extrusion method exhibited limited osteoconductive potency, but excellent space-maintaining capability. Further investigations are required to improve the processing method.

• Journal of the Korean Arthroscopy Society
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• v.3 no.2
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• pp.97-101
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• 1999

Purpose : The purpose of this study is to prevent thc graft-tunnel mismatch by measuring the patellar tendon length, intertunnel distance, tibial tunnel length and by obtaining appropriate bone block length. Materials and Methods : Authors analyzed 15 patients who had taken the anterior cruciate ligament reconstruction from March 1997 to June 1999. Tibial guide was always set on the "endo" $40^{\circ}$ position(Acufex, MA, USA). We measured the following indices, intertunnel distance(X), tibial tunnel length(T), patellar tendon length(N), tibia bone plug length(Y). Both of the femoral tunnel length(F) and the patellar bone plug length(P) were made in 25mm. The appropriate tibial bone plug length was simply calculated by subtracting the patellar tendon length from the sum of the intertunnel distance and thc tibial tunnel length(Y=X+T-N). Results : The average indices were as follows ; the intertunnel distance(X) was $23.4{\pm}1.4mm$, the tibial tunnel length(T) was $43.6{\pm}1.7mm$, the patellar tendon length was $40{\pm}2.4mm$, and the tibia bone plug length was $27{\pm}2.4mm$. Conclusion : In authors' endoscopic technique, establishment of individually determined optimal tibial bone plug length, based on total tunnel length and patellar tendon length could prevent the problem of graft-tunnel mismatch.

• 대한치주과학회:학술대회논문집
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• 2007.11a
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• pp.182-183
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• 2007

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.4
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• pp.376-381
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• 1999

A variety of materials and procedures such as sinus floor elevation, sinus-lift graft, inlay bone graft using Le Fort I osteotomy, and onlay graft have been used to create adequate bone volume in the maxillary sinus for placement of endosseous implants in the posterior atrophic maxilla. Because of the frequent lack of bone in the posterior maxilla, sinus lift procedure has become a commonly practiced treatment modality. The 138 endosseous implants of 36 patients with sinus augmentation procedures performed in Korea University Hospital from January 1991 to December 1998 were summarized and analysed. The result of this study were as follows: 1. Age ranged from 39 to 57, with a mean of 50.7. 2. The mean survival rate for 138 implants with maxillary sinus lift procedure was 80.4%. 3. There was no corelationship between the fixture length, width and the survival rate. 4. The result showed that the healing period for 8-12 months was necessary if the residual alveolar bone height was less than 5mm. 5. Autogenous iliac corticocancellous block graft showed the most favorable survival rate(95%).

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.1
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• pp.63-79
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• 1993

To repair bony defects with tansplanted bone in the body, fresh autogenous bone is undoubtly, the most effective bone graft for clinical applications. But the demineralized bone has the matrix-induced bone formation which was suggested by Urist in 1965. Many authors assisted that demineralized bone powder induces phenotypic conversion of mesenchymal cells into osteoblasts, with high-density bone formation. The process of inducing differentiated cells becomes osteogenic properties. The purpose of this study was to evaluate the osteoinductive capacity of allogenic freeze-dried demineralized bone block (FDD, $7{\times}7mm$) and to compare FDD with the same sue of deep-frozen allogenic bone(DF), fresh autogenous bone (A) after implantation. The histological and ultrastructural features of tissue responses were examined after 1, 2, 4, 6, 8 weeks implantation of each experimental groups in the operative site of the New Zealand white rabbits. The results were as follows : 1. Inflammatory cell infiltration generally has appeared at 1 week, but reduced at 4 weeks in each group, but most severe in DF group. 2. Osteoblastic activity has increased for 4 weeks, but decreased at 6 weeks in each group and there was no significant difference among experimental groups. 3. New bone formation has begun at 1week, least activations in A groups, and showed the revesal line of bone formation among each group at 6 to 8 weeks. 4. Bone resorption has appeared at 1 week, but disappeared at 4 weeks in both A and DF groups, but more severe in DF than A groups. 5. In ultrastructural changs, the DF group have showed the most remarkable osteoclastic activities among experimental groups. 6. Osteoid or tangled collagen fibrils near the implanted sites were replaced by more mature, lamellated bony trabeculae during bone remodeling. There was little difference among each experimental groups. 7. During the convertion osteoblasts to osteocytes which embedded within the bone matrix, there was organ-less-poor cytoplasm, increased nuclear chromatin, abundant rough endothelial reticulum (RER) in each groups. From the above the findings, the DF group shored more bone resorption and foreign body reaction than FDD and A groups, and FDD group showed more new bone formation or osteoblastic activity than DF and A groups in early stage. There was no significant difference of cellular activities among the FDD DF, and A groups according to the time.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.6
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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.