• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.2
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• pp.100-104
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• 2023

Autogenous bone grafts from the mandibular ramus are a known source of inadequate bone volume scenarios of the residual alveolar ridge. However, the conventional block-type harvesting technique cannot prevent bone marrow invasion, which can cause postoperative complications such as pain, swelling, and inferior alveolar nerve injury. This study aims to suggest a complication-free harvesting technique and present the results of bone grafting and donor sites. One patient received two dental implants with a complication-free harvesting technique that involves creation of ditching holes with a 1 mm round bur. Sagittal, coronal, and axial osteotomies produced grid-type cortical squares using a micro-saw and a round bur to confirm the cortical thickness. The grid-type cortical bone was harvested from the occlusal aspect, and the harvesting was extended through an additional osteotomy on the exposed and remaining cortical bone to prevent bone marrow invasion. The patient did not suffer postoperative severe pain, swelling, or numbness. After 15 months, the harvested site exhibited new cortical bone lining, and the grafted area had healed to a cortico-cancellous complex with functional loading of the implants. Our technique, grid-type cortical bone harvesting without bone marrow invasion, allowed application of autogenous bone without bone marrow invasion to achieve acceptable bone healing of the dental implants and to regenerate the harvested cortical bone.

• Journal of the Korea Concrete Institute
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• v.20 no.3
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• pp.291-298
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• 2008

Cracks in concrete generally interconnect flow paths and increase concrete permeability. The increase in concrete permeability due to the progression of cracks allows more water or aggressive chemical ions to penetrate into concrete, facilitating deterioration. The goal of this research is to study the relationship between crack width and water permeability of cracked concrete. Tests have been carried out as a function of hydraulic pressure (0.1 $\sim$ 2 bar) and crack width (30 $\sim$ 100 ${\mu}m$). Splitting and reuniting method was used to manufacture cracked concrete specimens with controlled crack width. Crack widths are checked by using a microscope($\times$100). The results show a considerable increase of water transport with crack width and hydraulic pressure. When the crack width is smaller than 50${\mu}m$, the crack width has little effect on concrete permeability. Due to the autogenous healing, the water flow through the crack gradually reduces with time. When crack width is 100 ${\mu}m$ and hydraulic pressure increase from 0.1 bar to 0.25 bar, concrete permeability increases rapidly about 190 times according to the test results.

• Journal of Periodontal and Implant Science
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• v.26 no.4
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• pp.907-931
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• 1996

The purpose of this study was to study of the effects of the bioglass and the natural coral on healing process of the alveolar bone defects. Three adult dogs aged 1 to 2 years were used in this study. Experimental alveolar bone defects were created surgically with surgical bur and bone chisel at the furcation area of the buccal surface of the right and left mandibular 3rd, 4th premolars. Twelve experimental alveolar bone defects were devided into four groups according to the type of graft materials. The groups were as follows : 1. flap operation with root planing & curettage(Negative control group) 2. flap operation with autogenous bone(Positive control group) 3. flap operation with bioglass(BG group) 4. flap operation with natural coral(NC group) At 2, 4, and 8 weeks, the dogs were serially sacrificed and specimens were prepared with Hematoxylin-Eosin stain for light microscopic evaluation. The results of this study were as follows : 1. The defect areas were filled with granulation tissue at two weeks in negative control group. But in other groups, the appearance of connective tissues around graft materials were formed more densely and the response of inflammation by graft materials itself was not found. 2. In every control and experimental groups at two weeks, there was seen the accumulation of the formation of new bone trabeculae at the bottom of defects and gradually expanded toward the graft materials and in autogenous group there was slightly seen the formation of new cementum. 3. There was seen the erosion of central portion of bioglass particles at two weeks in BG group, and the erosion of the central portion was developed more progressively and was filled with bone-like tissues at eight weeks. 4. The natural coral particles were encapsulated by densely connective tissues and seen the formation of new bone tissues at four weeks and developed more new bone and cementum formation at eight weeks. From the results of this study, the bioglass and the natural coral may be biocompatible and have a weak adverse reaction to the periodontal tissues.

• Journal of Veterinary Clinics
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• v.29 no.5
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• pp.412-415
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• 2012

A 1-year-old, castrated male Yorkshire terrier (case 1) and a 7-year-old female Poodle (case 2) presented with delayed union fractures. In case 1, the dog had a fractured right distal radius and ulna. In case 2, the dog had a fractured left distal tibia and fibula. A physical examination and radiographs performed in both dogs revealed delayed union fractures with large gaps. The fracture sites were fixed by bone plate and screws. Autogenous cancellous bone graft was applied into the fracture gap. To encourage rapid bone union, we used matrigel containing $20{\mu}g$ of recombinant human bone morphogenetic protein-2 (rhBMP-2) in the fracture site. Radiographs were taken postoperatively to monitor healing. Rapid bone union was noted in both dogs in long-term radiographs. In case 1, the radiographs revealed that the fracture gaps of the radius and ulna were bridged at 2 weeks. Fracture lines were not observed and normal appearance was restored at 20 weeks. In case 2, the radiographs showed that fracture repair had progressed at 11 weeks. The fractures healed faster than expected in these two cases. The results indicate that rhBMP-2 and matrigel may be effective and useful materials to enhance healing of delayed fractures.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.5
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• pp.457-464
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• 2008

Purpose: The aim of this study was to evaluate the clinical results of implants which were installed with maxillary sinus elevation by using lateral window technique. Materials and methods: We performed the maxillary sinus elevation by lateral window technique to 87 patients who visited Dept. of Oral & Maxillofacial Surgery, Chonnam National University Hospital from January, 2003 to January, 2007. When the residual bone height was from 3 mm to 7 mm, the sinus elevation and simultaneous implant installation was mostly performed. When the residual bone height was less than 3 mm, the sinus elevation was performed and the delayed implant installation was done after 5 or 6 months. No artificial membranes were used for coverage of the lateral bony window site and freeze dried fibrin sealant was applied to the grafted bone. The mean follow-up period was 28.5 months (ranged from 10 months to 48 months) Results: 1. Unilateral sinus elevations were performed in 51 patients and bilateral sinus elevations were performed in 36 patients. And the total number of sinus elevation procedure was 123 cases. 2. The sinus elevation and simultaneous implant installation was performed in 89 sinuses and 249 implants were installed. The sinus elevation and delayed implant installation was performed in 44 sinuses and 141 implants were installed. The total number of implants were 390 in 133 sinuses. The average healing period after sinus elevations was 6.1 months in delayed implant installation. 3. Only autogenous bone, autogenous bone mixing with allografts or autogenous bone mixing with xenografts were used as graft materials. 4. The average period from first surgery to second surgery was about 7.2 months. 5. Some patients complications, such as perforation of sinus membrane, swelling, infection and exposure of cover screw. Two implants were removed in the infected sinus. 6. The survival rate of implants with maxillary sinus elevation by lateral window technique was 99.5% and the success rate of implants was 95.1%. Conclusions: These results indicated that the implants which were installed with maxillary sinus elevation by lateral window technique showed high survival and success rates.

• Archives of Plastic Surgery
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• v.36 no.6
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• pp.679-684
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• 2009

Purpose: Human lipoaspirate cells are relatively easy to obtain in large quantities without cell culture. The aim of this in vitro pilot study was to determine the effect of cell therapy using uncultured lipoaspirate cells on cell proliferation and collagen synthesis of diabetic fibroblasts, which are the major contributing factors in wound healing. Methods: In order to get diabetic fibroblasts, dermis tissues were obtained from foot skin of diabetic patients who underwent debridements or toe amputations(n = 4). In order to isolate lipoaspirate cells, the same diabetic patients' abdominal adipose tissues were obtained by liposuction. The diabetic fibroblasts were co - cultured with or without autogenous lipoaspirate cells using porous culture plate insert. Initial numbers of the lipoaspirate cells and diabetic fibroblasts seeded were 15,000 cells/well, respectively. For cell proliferation assay, two treatment groups were included. In group I, diabetic fibroblasts were cultured with the insert having no cells, which serves as a control. In group II, the lipoaspirate cells were added in the culture plate insert. For collagen synthesis assay, one additional group(group III), in which diabetic fibroblasts were not seeded in the well and only lipoaspirate cells inside the insert were incubated without diabetic fibroblasts, was included for a reference. Results: One hundred to one hundred sixty thousand lipoaspirate cells were isolated per ml of aspirated adipose tissue. After 3 - day incubation, the mean cell numbers in group I and II were 17,294/well and 22,163/well. The mean collagen level in group I, II, and III were 29, 41, and 2 ng/ml, respectively. These results imply that both cell proliferation and collagen synthesis in the lipoaspirate cell treatment group were 28 and 44 percents higher than in the control group, respectively(p < 0.05). Conclusion: Uncultured lipoaspirate cell autografts may stimulate the wound healing activity of diabetic fibroblasts.

• Oral Biology Research
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• v.42 no.4
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• pp.198-207
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• 2018

Guided tissue regeneration (GBR) has been used to promote new bone formation in alveolar bone reconstruction at defective bone sites following tooth loss. Bone grafts used in GBR can be categorized into autogenous, xenogenous, and synthetic bones, and human allografts depending on the origin. The purpose of this study was to compare the rates of bone regeneration using two different bone grafts in the cranial defects of rabbits. Ten New Zealand rabbits were used in this study. Four defects were created in each surgical site. Each defect was filled as follows: with nothing, using a 50% xenograft and 50% human freeze-dried bone allograft (FDBA) depending on the volume rate, human FDBA alone, and xenograft alone. After 4 to 8 weeks of healing, histological and histomorphometric analyses were carried out. At 4 weeks, new bone formation occurred as follows: 18.3% in the control group, 6.5% in group I, 8.8% in group II, and 4.2% in group III. At 8 weeks, the new bone formation was 14.9% in the control group, 36.7% in group I, 39.2% in group II, and 16.8% in group III. The results of this study suggest that the higher the proportion of human FDBA in GBR, the greater was the amount of clinically useful new bone generated. The results confirm the need for adequate healing period to ensure successful GBR with bone grafting.

• Journal of Periodontal and Implant Science
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• v.34 no.1
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• pp.223-241
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• 2004

The purpose of this present study evaluated the osseous response around Ca-P coated xenogenic bone and compared osteogenic potential of Ca-P coated xenogenic bone to that of combination with type I collagen derived from bovine tendon as a biocompatible binder to prevent migration of bone particle on the repair of calvarial defects in rabbits. To study the effects of Ca-P coated xenogenic bone and collagen on bone healing, four 5-mm-diameter skull defect were made in calvaria with trephine filled with an autogenous bone chip or Ca-P coated xenogenic bone or Ca-P coated xenogenic bone and type I collagen (1:1 mixture by volume) or left empty. The defects were evaluated histologically at 1, 2, 4 and 8 weeks following implantation. Ca-P coated xenogenic bone at the calvarial defects of rabbits showed osteoconductivity at the margin of defect in the early stage of bony healing, but no direct contact with new bone was observed. With time passed by, it was resorbed slowly and showed consistent inflammatory reaction. An additional use of type I collagen derived from bovine tendon improved clinical handling, but no new bone formation was observed histologically. Above all, autogenous bone graft showed most prominent healing in quantity and density of new bone formation. According to this study, the use of Ca-P coated xenogenic bone alone and combination with type I collagen did not showed effective healing in quantity and density of new bone formation.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.4
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• pp.269-274
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• 1993

This is the case report of huge complex odontoma treated with sagittal splitting of buccal bone plate and iliac bone graft in left mandible angle. The 22 years old patient was admitted to the department of Oral and Maxillofacial Surgery of Kyungpook National University Hospital with the chief complaint of swelling on the left mandible angle area. We used extra oral Risdon incision and splitted the buccal cortical bone after making the horizontal bone cut buccally. The tumor mass was removed with cutting into the pieces with surgical bur to prevent mandibular fracture. The dead space was grafted with autogenous iliac bone graft and the splitted buccal cortical bone was fixed with two L-type miniplate. After 12months follow up check, we noticed good process of bone healing and satisfactory aesthetic result. In this case, my operative approach provided the excellent surgical access to the hard tissue mass and minimized post operative complication comparing with the conventional surgical approaches.

• The Journal of the Korean dental association
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• v.37 no.1 s.356
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• pp.62-68
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• 1999

Patients who present with severe maxillary bone loss Secondary to trauma or resorption provide a unique diagnosis and difficulty in implant installation. To solve this problem, various bone grafting methods and graft materials can be used in these compromised cases. But for the patients required wide reconstruction, autogenous iliac bone has been used widely because of easy harvesting of much corticocancellous bone. Usually, implant installations are performed 6-12 months later after grafting. but this method necessary long treatment period and additional surgery. To avoid this disadvantages, bone grafting with immediate implant installations are frequently used. But special care is necessary to prevent postoperative complication in this method. We present three cases of veneer grafting with immediate implant installation. These patients had a knife-edge shaped alveolar bone due to labial alveolar bone loss. We reconstructed this alveolar bone with veneer grafting with iliac bone and performed immediate implant installation. There was no complications during healing periods in these three cases. Six months later, we found good survival of grafting bone and osseointegration of these implants, so we could perform prosthetic treatment successfully.