• Journal of Periodontal and Implant Science
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• 제50권6호
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• pp.379-391
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• 2020

Purpose: The aims of this study were to evaluate the 5-year cumulative survival rate (CSR) of implants placed with guided bone regeneration (GBR) compared to implants placed in native bone, and to identify factors contributing to implant failure in regenerated bone. Methods: This retrospective cohort study included 240 patients who had implant placement either with a GBR procedure (regenerated bone group) or with pristine bone (native bone group). Data on demographic features (age, sex, smoking, and medical history), location of the implant, implant-specific features, and grafting procedures and materials were collected. The 5-year CSRs in both groups were estimated using Kaplan-Meier analysis. Risk factors for implant failure were analyzed with a Cox proportional hazards model. Results: In total, 264 implants in the native bone group and 133 implants in the regenerated bone group were analyzed. The 5-year CSRs were 96.4% in the regenerated bone group and 97.5% in the native bone group, which was not a significant difference. The multivariable analysis confirmed that bone status was not an independent risk factor for implant failure. However, smoking significantly increased the failure rate (hazard ratio, 10.7; P=0.002). Conclusions: The 5-year CSR of implants placed in regenerated bone using GBR was comparable to that of implants placed in native bone. Smoking significantly increased the risk of implant failure in both groups.

• 대한치과의사협회지
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• 제47권3호
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• pp.122-130
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• 2009

For the successful guided bone regeneration(GBR) of maxillary bony defect, proper soft tissue coverage is one of the most important things. Soft tissue dehiscence can be most common reason of osseous reconstruction failure. If a vascular supply to the graft should not develop from the host tissue, then the graft may also foil. Both of these prerequisites can be aided by judicious use of the buccal fat pad(BFP). Many methods for adequate soft tissue coverage have been proposed and the use of the BFP is one of them. BFP is useful in posterior maxillary area, can cover larger area and have higher blood flow than other methods. so the use of the BFP may offer protection and early blood supply to maxillary bone graft. This report describes the history, anatomy, blood flow, and clinical usefulness with two clinical cases.

• Journal of Periodontal and Implant Science
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• 제32권3호
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• pp.577-588
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• 2002

Osseointegrated implants have been established as the standard treatment modality for full/partial edentulous patients since the 1960's, and the long term results for full edentulous patients have proven to be successful. Based on these results osseointegrated implants are now widely used for partial edentulous patients. There has been an increased interest towards the efficacy of wide implants, despite many reports mentioning the lower success rate of wide implants compared to regular implants. Recently, mandibular molar area defects are commonly restored using 2 wide implants, but it is not determined whether which treatment modality-3 regular implants or 2 wide implants-shows superior success rate. In this study, 2 wide implants and 3 regular implants used for the restoration of mandibular molar area are used to compare the survival rate of 1-4 years, and to analyze and compare the failure factors. The following conclusions could be drawn from this study. 1. Wide implants and regular implants showed 94.5% and 97,6% of survival rate respectively. After prosthodontic work, the survival rate was 100% and 98.1% for wide implants and regular implants respectively. 2. 5 failed implants have been removed. 2 wide implants and 1 regular implant have been removed due to failure of osseointegration. 1 wide implant was removed due to abscess formation caused by over-heating, and 1 regular implant was removed due to mechanical failure caused by over-loading within the first year of function. 3. No statistically significant difference was observed with respect to the amount of marginal bone loss of wide and regular implants.(P>0.05) In conclusion, restoration of the mandibular molar area using 3 regular implants was found to be a good treatment modality, and 2 wide implants could he considered a good treatment modality when success factors are taken into account.

• 한국건설관리학회논문집
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• 제10권4호
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• pp.67-75
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• 2009

최근 활발히 진행되고 있는 도시재생사업과 같은 대규모 복합개발사업은 사업기간이 길고 다양한 사업주체들이 참여한다. 이러한 특성 때문에 사업추진 과정상 많은 위험요인들을 내포하게 되고 이를 관리하는 것은 사업의 성패에 큰 영향을 미친다. 그러므로 도시재생사업에서 위험을 인지하고 대응하는 일련의 위험관리 과정은 정확하고 체계적으로 수행되어야 한다. 위험관리과정에서 위험인지단계는 다양한 위험요인을 인지하고 그 위험의 성격을 규정하는 첫 단계이며, 위험을 인지하는 기법 체크리스트는 가장 보편적이고 실용적인 방법이라고 할 수 있다. 따라서 본 연구에서는 도시재생사업의 개발단계에서 사업주체들의 업무를 분석하고, 위험요인을 도출하여 사업주체별로 위험을 분류하는 체크리스트를 제안하였다. 이러한 주체별 위험인지 체크리스트는 실무자가 쉽게 위험을 파악할 수 있는 도구로써, 도시재생사업과 같이 다양한 사업주체들이 자신은 물론 다른 사업 참여자들의 위험을 인지하는데도 효과적일 것이라고 기대된다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.487-490
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• 2008

최근 활발히 진행되고 있는 도시재생사업과 같은 대규모 복합개발사업은 사업기간이 길고 다양한 사업주체들이 참여한다. 이러한 특성 때문에 사업추진 과정상 많은 위험요인들을 내포하게 되고 이를 관리하는 것은 사업의 성패에 큰 영향을 미친다. 그러므로 도시재생사업에서 위험을 인지하고 대응하는 일련의 위험관리 과정은 정확하고 체계적으로 수행되어야 한다. 위험관리과정에서 위험인지단계는 다양한 위험요인을 인지하고 그 위험의 성격을 규정하는 첫 단계이다. 위험을 인지하는 기법 중 체크리스트는 가장 보편적이고 실용적인 방법이라고 할 수 있다. 따라서 본 연구에서는 도시재생사업의 개발단계에서 사업주체들의 업무를 분석하고, 위험을 도출하여 사업주체별로 위험을 분류하는 체크리스트를 제안하였다. 이러한 주체별 위험요인 체크리스트는 실무자가 쉽게 위험을 파악할 수 있는 도구로써, 도시재생사업과 같이 다양한 사업주체들이 자신은 물론 다른 사업 참여자들의 위험을 인지하는데도 효과적일 것이라고 기대된다.

• Journal of Periodontal and Implant Science
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• 제38권3호
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• pp.535-542
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• 2008

Purpose: The aim of this retrospective study is to evaluate survival rate of implant and bone formation, to analyze failure contribution factor. Material and Methods: A total of 52 consecutive patients(35 male, 17 female, mean age 49 years) with 104 osseous defects were treated during the period from October 2004 to June 2007 with a simultaneous or staged GBR approach using non-resorbable or resorbable membranes combined with autogenous bone grafts or xenograft(Bio-Oss, Bio-cera, BBP). Result: A total of 32(30,8%) of 104 GBR-treated sites failed the bone formation and a total of 5(5.6%) of 89 implants were removed. Early exposure of the membrane has significantly affected bone formation(p<0.05). Non-resorbable membrane showed more exposure of the membrane and low success rate of bone formation than resorbable membrane(p<0.05). There were no difference between success rate of bone formation and using autogenous bone or graft materials. There were no statistically significant difference between success rate of bone formation and smoking or using PRP. Mandible showed more success rate of bone formation than maxilla(p<0.05). Conclusion: Early exposure of the membrane, membrane type and maxilla/mandible type have influence on success rate of bone formation during GBR.

• Animal cells and systems
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• 제2권1호
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• pp.1-8
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• 1998

Hepatocyte growth factor (HGF), originally discovered and cloned as a powerful mitogen for hepatocytes, is a four kringle-containing growth factor which specifically binds to membrane-spanning tyrosine kinase, c-Met/HGF receptor. HGF has mitogenic, motogenic (enhancement of cell movement), morphogenic (e.g., induction of branching tubulogenesis), and anti-apoptotic activities for a wide variety of cells. During embryogenesis, HGF supports organogenesis and morphogenesis of various tissues, including liver, kidney, lung, gut, mammary gland, and tooth. In adult tissues HGF elicits an organotrophic function which supports regeneration of organs such as liver, kidney, lung, and vascular tissues. HGF is also a novel member of neurotrophic factor in nervous systems. Together with the preferential expression of HGF in mesenchymal or stromal cells, and c-Met/HGF receptor In epithelial or endothelial cells, the HGF-Met coupling seems to orchestrate dynamic morphogenic processes through epithelial-mesenchymal (or-stromal) interactions for organogenesis and organ regeneration. HGF or HGF gene may well become unique therapeutic tools for treatment of patients with various organ failure, through its actions to reconstruct organized tissue architectures. This review focuses on recently characterized biological and physiological functions integrated by HGF-Met coupling during organogenesis and organ regeneration.

• Journal of Periodontal and Implant Science
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• 제51권6호
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• pp.433-443
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• 2021

Purpose: This study aimed to evaluate the effectiveness of the partial split-flap technique with a K-incision on vertical guided bone regeneration (vGBR) and to retrospectively analyze the clinical and radiographic outcomes of dental implantation using this approach. Methods: In total, 78 patients who received 104 dental implants with vGBR, categorized as (1) pre-GBR and post-implantation and (2) simultaneous GBR and implantation, were enrolled. Data analysis was based on periapical radiographs, clinical photos, and dental records. The 2-sample t-test was used to compare the 2 surgical procedures. Results: The baseline vertical bone level, augmented bone height (ABH), and treatment duration were significantly higher in the pre-GBR procedure group. The survival rates of the implants were 96.1% and 94.8% in implant- and patient-based analyses, respectively. In Cox regression analysis, high rates of implant failure were found in the presence of ABH of ≥4 mm, smoking, and diabetes. Conclusions: Within the limitations of this retrospective study, the partial split-flap technique using a K-incision for vGBR showed stable clinical outcomes and favorable dental implant survival.

• 대한의생명과학회지
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• 제30권1호
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• pp.10-16
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• 2024

Oxidative stress caused by elevated reactive oxygen species (ROS) in the heart causes various heart diseases. Oxidative stress is known as a factor that causes diseases in various organs as well as the heart. Diseases such as heart failure, myocardial infarction, and cardiomyopathy caused by oxidative stress in the heart can be treated with medication or surgery. Recently, blood cells concentrate (BCC) is used in various treatment areas such as orthopedics, gynecology, and urology. BCC therapy is applied to treatment by concentrating platelets and white blood cells necessary for regeneration through simple centrifugation using autologous blood. As the platelets are activated, many growth factors are released from alpha granules of the platelets. Growth factors such as TGF-β1, PDGF, VEGF, and EGF derived from platelets are involved in various cell signaling pathway. Due to these growth factors, BCC can contribute to tissue regeneration and can treat various diseases. CD34+ cells contained in BCC may also play an important role in tissue regeneration. In this study, we investigated whether BCC has a regenerative effect on heart disease, and if so, what mechanism causes the effect. To observe this, cardiomyocyte cells were treated with H₂O₂ to induce oxidative stress. And the effect was confirmed in the presence or absence of BCC. As a result, in the presence of BCC, the oxidative stress of cardiomyocyte cells was reduced and cell damage was also reduced. These results suggest that BCC therapy can be a new treatment alternative for heart disease.

• Journal of Periodontal and Implant Science
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• 제52권3호
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• pp.230-241
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• 2022

Purpose: The purpose of this study was to evaluate failed implants and reimplantation survival and to identify the relative risk factors for implant re-failure. Methods: Ninety-one dental implants were extracted between 2006 and 2020 at the National Health Insurance Service Ilsan Hospital, including 56 implants in the maxilla and 35 implants in the mandible that were removed from 77 patients. Patient information (e.g., age, sex, and systemic diseases) and surgical information (e.g., the date of surgery and location of the implants and bone grafts) were recorded. If an implant prosthesis was used, prosthesis information was also recorded. Results: In total, 91 first-time failed dental implants in 77 patients were analyzed. Of them, 69 implants in 61 patients received reimplantation after failure. Sixteen patients (22 implants) refused reimplantation or received reimplantation at a different site. Eight of the 69 reimplants failed again. The 1-year survival rate of the 69 reimplants was 89.4%. Age at reimplantation and smoking significantly increased the risk of reimplantation failure. However, a history of taking anti-thrombotic agents showed a statistically significant negative association with reimplantation failure. Of the failed implants, 66% showed early failure and 34% showed late failure of the initial implantation. All 8 re-failed implants showed early failure. Only 3 of these 8 failed reimplants were re-tried and the second reimplants all survived. Conclusions: The total survival rate of implants, which included reimplants and second reimplants was 99.2%, although the survival rate of the initial implantations was 96.3%. Previous failure did not affect the success of the next trial. Reimplantation failure was more strongly affected by patient factors than by implant factors. Therefore, each patient's specific factors need to be meticulously controlled to achieve successful reimplantation.