• Journal of Periodontal and Implant Science
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• v.34 no.1
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• pp.177-193
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• 2004

Several experimental studies showed that the application of small amounts of electric current to bone stimulated osteogenesis at the site of the cathode and suggested that electrical currents promote osseointegration around dental implants. The purpose of this study was to determine the effect of direct microcurrent to endosseous titanium implants placed in bone defects. The right and left 2nd, 3rd and 4th mandibular premolars in ten mongrel dogs (15Kg of weight) were extracted. One monthe later, Ti-machined screw type implants(3.8 mm diameter x 8.5 mm length, $AVANA^{(R)}$, Ostem) were placed in surgically created circumferential defect area(width 5mm, depth 4mm). The implants were divided into three groups according to the treatment modalities: Control group- implants without electrical stimulation; Experimental group I- implants with allogenic demineralized freeze dried bone grafting; and Experimental group II-implants allogenic demineralized freeze dried bone grafting and electric stimulation. The animals were sacrificed in the 4th and 8th week after implant placement and un-decalcified specimens were prepared for histological and histometrical evaluation of bone-implant contact ratio (BIC) and bone formation area ratio (BFA) in defect area. Some specimens at 8 weeks after implantation were used for removal torque testing. Histologically, there was connective tissue infiltration in the coronal part of defect area in control and the experimental group I, whereas direct bone contact was found in the experimental group II without connective tissue invasion. Average BIC ratios at 4 weeks of healing were 60.1% in the experimental group II, 47.4% in the experimental group I and 42.7% in the control. Average BIC ratios at 8 weeks after implantation were 67.6% in the experimental group II, 55.9% in the experimental group I and 54.6% in the control. The average BFA ratio was 84.0% in the experimental group II, 71.8% in the experimental group I and 58.8% in the control at 4 weeks, and the BFA ratios were 89.6% in the experimental group II, 81.4% in the experimental group I and 70.5% in the control at 8 weeks after implantation. The experimental group II showed also significantly greater BIC and BFA ratios compared to the control and the experimental group I (p<0.05). The removal torque values at 8 weeks after implantation were 56 Ncm in the experimental group II, 49 Ncm in the experimental group I and 43 Ncm in the control. There was a statistically significant difference among 3 groups (p<0.05). These results suggest that electrical stimulation improve and accelerate bone healing around endosseous titanium implants in bone defect.

• Journal of the Korean Orthopaedic Association
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• v.55 no.2
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• pp.127-134
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• 2020

Purpose: The aims of this study were (1) to investigate the relationship between the characteristics of allogenic bone block and the compressive strength of an allogenic bone block measured by biomechanical experiments, and (2) to compare the maximum pressure load of allogenic bone block with the gap pressure measured at the high tibial opening osteotomy. Materials and Methods: Ten patients who provided informed consent for gap pressure measurements during opening wedge high tibial osteotomy (OWHTO) were included. The gap pressures were measured at 1 mm intervals while opening the osteotomy site from 8 mm to 14 mm. Seventeen U-shaped allogenous wedge bone blocks were made from the femur, tibia, and humerus. The height, width, cross-sectional area, and cortex thickness of the bone blocks were measured, along with the maximum compressive load just before breakage. The relationship between these characteristics and the maximum pressure load of the bone blocks was evaluated. The gap pressures measured in OWHTO were compared with the maximum pressure loads of the allogenous wedge bone blocks to evaluate the possibility of inserting allogenous wedge bone blocks into the osteotomy site without a distractor in OWHTO. Results: The OWHTO gap pressure increased with increasing osteotomy site opening. The mean gap pressure, which occurred at a 14-mm opening, was 282±93 N; the maximum pressure was 427 N. The maximum pressure load of the allografts was 13,379±6,469 N (minimum, 5,868; maximum, 29,130 N) and was correlated significantly with the cortical bone thickness (correlation coefficient=0.693, p=0.002) and cross-sectional area (correlation coefficient=0.826, p<0.001). Depending on the sterilization method, the maximum pressure loads for the bone blocks were 13,406±5,928 N for freeze-dried and 13,348±7,449 N for fresh frozen. The maximum compressive load of the allogenous wedge bone blocks was 13.7-times greater than that in OWHTO opened to 14 mm (5,868 N vs. 427 N). Conclusion: The compressive strength of allogenous wedge bone blocks was sufficiently greater than the gap pressure in OWHTO. Therefore, allogenous wedge bone blocks can be inserted safely into the osteotomy site without a distractor.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.1
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• pp.9-15
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• 2006

Peripheral bood stem cell collection (PBSCC), including peripheral blood stem cell transplantation (PBSCT), has been utilized worldwide as a very beneficial treatment method instead of allogenic Bone Marrow Transplantation (BMT) because it has many advantages such as rapid bone marrow engraftment and hematopoietic recovery, easy and safe accessibility and lower risk of rejection compared with allogenic BMT. In order to identify most the observable parameter in PBSCC, we analyzed various hematological parameters before and after PBSCC, and evaluated the correlation between the time of bone marrow engraftment and the number of CD34+ cells. Thirteen patients, who underwent 54 PBSCCs from January, 2003 to August, 2004 at Chungnam National University Hospital due to various systemic neoplasms, were analyzed in aspects of various hematological parameters including CD34+ cells using by Flow Cytometry (FCM). PBSCC harvests are described below: Mononuclear cells (MNC) $2.3{\pm}1.4{\times}10^8/kg$ and CD34+ cells $0.63{\pm}0.35{\times}10^6/kg$ on average, respectively. There was a statistical significance in Hb and Hct before and after PBSCC, but not in WBC and platelet counts. The period to reach the hematological bone marrow engraftment was 13.4(10~21) days and 19.5(11~38) days according to the criteria of absolute neutrophile counts (ANC) ${\geq}500/uL$ and platelet counts ${\geq}50,000/{\mu}L$ in peripheral blood, respectively. There was a significant correlation between the numbers of CD34+ cell and ANC (p<0.05), and a borderline significance between MNC and ANC (p=0.051). We found that a group of patients, who were infused with CD34+ cells more than $3.5{\times}10^6/kg$, reached more rapidly the period of bone marrow engraftment in platelet counts (p=0.040). This present study suggested that Hb and Hct were the most useful parameters and should be closely monitored before and after PBSCC, that a PBSCT with the dosage of more than $3.5{\times}10^6/kg$ of CD34+ cells was needed to perform successful bone marrow engraftment, and additionally that platelet counts could be more useful in indicating bone marrow engraftment than ANC.

• Tuberculosis and Respiratory Diseases
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• v.49 no.2
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• pp.207-216
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• 2000

Background : The occurrence of lung complications after allogenic bone marrow transplantation(BMT) has been reported as 40-60 percent. The risk factors for lung complications are whole body irradiation, high dose chemotherapy, graft versus host disease, old age and CMV infection. The prevalence of graft versus host disease is less in Korea than in Western countries, but frequency of CMV infection is higher. Therefore, the pattern of lung complications may be different in Korea from those in Western countries. Methods : A retrospective cohort study was performed on one hundred consecutive adult patients who underwent allogenic bone marrow transplantation from December, 1993 to May, 1999 at Asan Medical Center. Lung complications were divided into two groups by the time of development, within 30days (pre-engraftment) and beyond 30 days (post-engraftment), and then subdivided into infectious and non-infectious complication. Infectious complications were defined as having the organism in blood, BAL fluid, pleural fluid or sputum, or compatible clinical findings in patients, which improved with antibiotics or an anti-fungal therapy. Result: 1) Eighty three episodes of lung complications had occurred in 54 patients. 2) Within thirty days after BMT, non-infectious complications were more common than infections, but this pattern was reversed after 30 days. After one year post-BMT, there was no infectious complication except in cases of recurrence of underlying disease or development of chronic GVHD. 3) Among the non-infectious complications, pleural effusion (27 episodes) was most common, followed by pulmonary edema (8 episodes), bronchiolitis obliterans(2 episodes), diffuse alveolar hemorrhage (1 episode) and bronchiloitis obliterans with organizing pneumonia (1 episode). 4) The infectious complications were pneumonia (bacterial: 9 episodes, viral: 4 episodes, fungal : 5 episodes, pneumocystis carinii : 1 episode), pulmonary tuberculosis(3 episodes) and tuberculous pleurisy (3 episodes). 5) Lung complications were more frequent in CMV positive patients and in patients with delayed recovery of neutrophil count. 6) The mortality was higher in the patients with lung complications. Conclusion : Lung complications developed in 54% after allogenic BMT and were associated with higher mortality.

• The Journal of Korean Academy of Prosthodontics
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• v.33 no.2
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• pp.300-316
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• 1995

Methods for restoring the posterior portion of the maxilla with delayed and simultaneous sinus lift, composite graft and placement of TPS cylinder and screw type implants are presented. Sinus grafting is needed because of minimal remaining alveolar bone and supporting posterior maxillary portion, The composite graft material uses a combination of autogeneous bone from tuberosity, dimeneralized freeze dried allogenic bone and hydroxylapatite with saline. Since 1991, feb, 1 sinus graft with delayed implantation of 3 cylinder implants and 5 sinus grafts with simultaneous placement of 4HA coated screw typed, 8 TPS cylinder typed implants have been performed for 6 patients. None of the 15 restored implants have been lost, Temporization of prosthesis was done about 2-5 months before final prosthetic work, None of them shows any severe complication.

• Journal of the Korean Arthroscopy Society
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• v.7 no.2
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• pp.147-152
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• 2003

Purpose : The purpose of this study was to evaluate the arthroscopic findings of the transplanted human allogenic meniscus including MRI changes at follow up. Materials and Methods : From Oct. 1999 to Jun. 2002, nine patients underwent arthroscopic evaluation at follow-up. We used nonirradiated cryopreserved meniscus allograft for 6 cases and fresh-frozen for 3 cases. We used bone-plug method for medial meniscus and bone-bridge method for lateral meniscus to fix the transplanted meniscus. The average follow-up time was 13 months. We evaluated the result by lysholm score, MRI and second-look arthroscopic finding. Results : The second-look arthroscopy after allogenic meniscal transplantation revealed that grafts were well incorporated with surrounding capsular tissue. But one case showed wear on the post horn and the other case which was operated at other local clinic showed tear of the anterior hem due to non-anatomic placement of bone bridge. There was improvement of average Lysholm score form 64 to 87. Conclusion : Second-look arthroscopy revealed excellent incorporation of the allograft with firm attachment and early clinical results are satisfactory. But further studies are necessary to assess whether meniscal transplantation can prevent progressive degenerative changes.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.20 no.2
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• pp.139-147
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• 1998

This study has been performed to evaluate the relationship between the remained mineral components in a decalcified bone matrix and an ectopic bone formation efficiency. The freezed rat diaphyseal cortical bones measuring 0.5cm in length were demineralized in heated 0.6N HCl at $60^{\circ}C$ for 5, 10, 15, 20, 25, 30, 35, 40 minutes, respectively, using a controlled heat ultrasonic cleaner. Each 1cc of decalcifying solution taken during decalcification procedure was used to calculate calcium content using calcium dignostics kit under 600nm of spectrophotomer. After decalcification, each specimen was also weighed. Then each prepared specimen was implanted into the dorsal pouch of 24 Sprague-Dawley rats divided into 8 groups by time course. The implants were harvested at 1, 2, and 3 weeks and prepared for routine H-E stain specimens to evaluate osteogenic activity. The results are as follows: 1. There was statistical significant difference in change of calcium concentration up to demineralization of 30 minutes and each allogenic bones decalcifed up to 20 minutes revealed 99.65% of decalcification in average. 2. There was statistical significant difference in change of weight in demineralized allogenic bone up to 20 minutes treatment but, no significant change was noted after that time. 3. The histologic analysis revealed active ectopic bone formation in the implanted allografts demineralized for 20, 25, 30 minutes, respectively. However, the other groups of allografts showed relatively poor osteoinductive activity. These findings suggest that complete decalcification with a minimized degeneration of collagen matrix is necessary to induce maximal osteogenesis by decalcified bone allograft.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.2
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• pp.137-152
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• 1995

This study was designed to evaluate the bone formation capability of the bone substitute when compared with autogenic bone, freeze-dried demineralized allogeneic bone and bioglass into parietal bone of the rats. We made the parietal bone defects in $7{\times}7mm$ size on rats and has performed the bone graft in each experimental groups. Postoperatively 1, 2, 4, 6, 8, weeks, each specimen stained with H & E, Masson's trichrome methods. We evaluated the osteogensis capability in each groups. The result were as follow : 1. Inflammatory cell infiltration approached at 1 week and disappeared at 4 weeks in all experimental group, expecially severe in freeze-dried demineralized allogeneic bone group. 2. New capillry proliferation was increased in autogeneic bone graft group than any other groups and was increased till 2 weeks and decreased in freeze-dried demineralized allogeneic bone group and was few in bioglass group. 3. Osteoblastic activity increased in autogeneic bone and freeze-dried demineralized allogeneic bone groups till 4 weeks, and decreased in 6 weeks which no difference between these groups. But, few occurred in bioglass group till 6 weeks. 4. Initial osteoclastic activity was prominent in freeze-dried demineralized allogeneic bone group and few in autogeneic bone group. 5. New bone formation bega at 1 week in autograft and freeze-dried demineralized allogenic bone groups, but, mild new bone formation at 8 weeks in bioglass.

• The Journal of the Korean dental association
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• v.48 no.4
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• pp.256-262
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• 2010

bone grafting is indicated in the case of bony defects and is classified into autograft, allograft, and xenograft. Synthetic bone graft is contrasted with these three categories in that it has a different donor source. Autograft is most prominent as it is known as a gold standard of all grafting procedures. Its principles and practices are well established via accumulated informations and clinical experiences, which imposes no regulations or restrictions in its clinical use. On the other hand, other bone graft procedures are under tight control for the safety and effectiveness of each product. Food and Drug Administration of the United States has a system in which the information on the approvals and clearances of bone graft materials on their internet homepage. All the bone graft materials that are under the regulations of the United States are classified into the category of medical devices, which includes allogenic bone, xenogenic bone, and synthetic bone graft materials. Each bone graft material has its own indication and the FDA approvals and clearances of medical devices contain the item of "intended use" to specify the indications of each bone graft materials. US dentists, as users of the specific bone graft materials, are provided with adequate information on the approved materials they are to utilize. As an user of these materials, Korean dentists are less provided with the information on the bone graft materials they want to use. Medical providers of the bone graft materials have to be able to provide their users with the essential information such as the intended use of the regulatory approval. Dentists must also be active in gathering informations on the material of their interest, and the system must be built in which both of the medical providers and users of bone graft materials can be satisfied in providing and getting the information, respectively.

• Implantology
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• v.22 no.4
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• pp.242-254
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• 2018

The aim of the current study was to evaluate the results of horizontal guided bone regeneration (GBR) with xenograf t (deproteinized bovine bone mineral, DBBM), allograf t (irradiated allogenic cancellous bone and marrow), titanium membrane, resorbable collagen membrane, and advanced platelet-rich fibrin (A-PRF) in the anterior maxilla. The titanium membrane was used in this study has a three-dimensional (3D) shape that can cover ridge defects. Case 1. A 32-year-old female patient presented with discomfort due to mobility and pus discharge on tooth #11. Three months after extracting tooth #11, diagnostic software (R2 GATE diagnostic software, Megagen, Daegu, Korea) was used to establish the treatment plan for implant placement. At the first stage of implant surgery, GBR for horizontal augmentation was performed with DBBM ($Bio-Oss^{(R)}$, Geistlich, Wolhusen, Switzerland), irradiated allogenic cancellous bone and marrow (ICB $cancellous^{(R)}$, Rocky Mountain Tissue Bank, Denver, USA), 3D-titanium membrane ($i-Gen^{(R)}$, Megagen, Daegu, Korea), resorbable collagen membrane (Collagen $membrane^{(R)}$, Genoss, Suwon, Korea), and A-PRF because there was approximately 4 mm labial dehiscence after implant placement. Five months after placing the implant, the second stage of implant surgery was performed, and healing abutment was connected after removal of the 3D-titanium membrane. Five months after the second stage of implant surgery was done, the final prosthesis was then delivered. Case 2. A 35-year-old female patient presented with discomfort due to pain and mobility of implant #21. Removal of implant #21 fixture was planned simultaneously with placement of the new implant fixture. At the first stage of implant surgery, GBR for horizontal augmentation was performed with DBBM ($Bio-Oss^{(R)}$), irradiated allogenic cancellous bone and marrow (ICB $cancellous^{(R)}$), 3D-titanium membrane ($i-Gen^{(R)}$), resorbable collagen membrane (Ossix $plus^{(R)}$, Datum, Telrad, Israel), and A-PRF because there was approximately 7 mm labial dehiscence after implant placement. At the second stage of implant surgery six months after implant placement, healing abutment was connected after removing the 3D-titanium membrane. Nine months after the second stage of implant surgery was done, the final prosthesis was then delivered. In these two clinical cases, wound healing of the operation sites was uneventful. All implants were clinically stable without inflammation or additional bone loss, and there was no discomfort to the patient. With the non-resorbable titanium membrane, the ability of bone formation in the space was stably maintained in three dimensions, and A-PRF might influence soft tissue healing. This limited study suggests that aesthetic results can be achieved with GBR using 3D-titanium membrane and A-PRF in the anterior maxilla. However, long-term follow-up evaluation should be performed.