• International Journal of Stem Cells
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• 제16권3호
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• pp.304-314
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• 2023

Background and Objectives: Ear cartilage malformations are commonly encountered problems in reconstructive surgery, since cartilage has low self-regenerating capacity. Malformations that impose psychological and social burden on one's life are currently treated using ear prosthesis, synthetic implants or autologous flaps from rib cartilage. These approaches are challenging because not only they request high surgical expertise, but also they lack flexibility and induce severe donor-site morbidity. Through the last decade, tissue engineering gained attention where it aims at regenerating human tissues or organs in order to restore normal functions. This technique consists of three main elements, cells, growth factors, and above all, a scaffold that supports cells and guides their behavior. Several studies have investigated different scaffolds prepared from both synthetic or natural materials and their effects on cellular differentiation and behavior. Methods and Results: In this study, we investigated a natural scaffold (alginate) as tridimensional hydrogel seeded with progenitors from different origins such as bone marrow, perichondrium and dental pulp. In contact with the scaffold, these cells remained viable and were able to differentiate into chondrocytes when cultured in vitro. Quantitative and qualitative results show the presence of different chondrogenic markers as well as elastic ones for the purpose of ear cartilage, upon different culture conditions. Conclusions: We confirmed that auricular perichondrial cells outperform other cells to produce chondrogenic tissue in normal oxygen levels and we report for the first time the effect of hypoxia on these cells. Our results provide updates for cartilage engineering for future clinical applications.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권6호
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• pp.527-537
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• 2007

To evaluate criteria, indications, and prognosis of the various reconstructive methods on the patients with intraoral soft tissue defect who had been treated at Dept. of Oral and Maxillofacial Surgery, Pusan National University Hospital from 2003 to 2005, we have reviewed the clinical data of the patients and analysed. The results were as follows: 1. Tongue flaps have been mainly applied on anterior portion of palate and maxilla. The survival rate was high percent, but the cooperation of patient was inevitable for the success. 2. Palatal mucosa rotational flaps were available on relative large defect on palate, oroantral fistula site. The side effect was a scaring band from secondary healing on denuded donor palate site. Sometimes the band came to be a hinderance to swallowing, phonation. 3. Forearm free flap was a workhorse flap for everywhere in intraoral defects. We had used the flap on cheek, floor of mouth, tongue without any significant complications. But the application of the flap was required for long operation time, which was disadvantageous to the old, weak patients. 4. Cervical platysmal flap could be easily applicable for buccal cheek, floor of mouth after excision of the cancer lesion. The design of the flap could be made simultaneously on neck dissection, but the danger of cancer remnants on the flap always might be remained. 5. Buccal fat pad pedicled flap must have been a primary flap for repair of oroantral fistula especially on posterior maxilla. The flap survival will be expected if the considerations for above reconstructive methods on site, size, condition of defects primarily could be made.

• 자원환경지질
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• 제51권2호
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• pp.77-85
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• 2018

원전 시설 주변 및 심지층 폐기물 처분장 인근 환경은 우라늄으로 오염될 가능성이 높으며, 오염된 우라늄은 지하수를 따라 먼 곳까지 이동 및 확산될 수 있다. 이러한 오염 우라늄의 이동 및 확산을 효과적으로 제어하기 위해서는 지하 환경에서 우라늄의 생지화학적 거동을 이해할 필요가 있다. 일반적으로 토양 및 지질 매체 내에 다양한 종류의 미생물이 생존하고 있으며, 이들의 활동은 핵종들의 산화 환원 반응 및 그에 따른 용해도 변화와 밀접히 연관되어 있다. 우리는 유기물 대신 수소 가스를 전자공여체로 사용하여 고체 매질에 대한 용존 우라늄의 수착 및 침전 거동을 살펴보았다. 화강암을 고체 매질로 사용한 회분식 실험에서는 수소의 영향이 관찰되지 않았으나, 벤토나이트를 사용한 조건에서는 수소의 영향으로 5~8% 우라늄 농도 감소가 관찰되었다. 이러한 결과는 벤토나이트 토착미생물이 수소를 전자공여체로 활용하여 우라늄 거동(감소)에 영향을 준 것으로 보인다. 또한, 폐기물 처분환경의 고열 및 고방사선 조건에서도 벤토나이트 토착미생물은 강한 내성을 보였으며, 이는 향후 자연산 벤토나이트가 처분장 완충재로 사용될 경우 핵종-생지화학 반응이 주요 기작 중의 하나가 될 것으로 예상된다.

• Journal of Periodontal and Implant Science
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• 제37권3호
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• pp.625-636
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• 2007

Marginal tissue recession makes problems like esthetics, root caries, hypersensitivity and plaque accumulation. Request for root coverage is higer than ever, especially esthetic problems involved. So techniques for root coverage hav been developed. There are some kinds of surgical techniques using soft tissue for root coverage. For example, free gingival graft, kinds of pedicle flap, subepithelial connective tissue graft(SCTG), and so on. Subepithelial connective tissue graft has many advantage for root coverage, that is less pain on donor site, good blood supply for graft, and more esthetic result. For this reaseon, this case report was performed to evaluate the effect of root coverage using subepithelial connective tissue graft. Three patients has Miller's class I marginal tissue recession and one patients has Miller's class III marginal tissue recession. The following period is 36.5 month on average. The results are as follows: 1. Root coverage of 100% was obtained in 5 of 6 defects, and 80% was obtained in 1 of 6 defects, The mean root coverage was 96,6% in six cases on 4 patients. 2. The mean root coverage was 3.83mm and mean recession depth decreased from 4mm to 0.16mm. 3. The mean width of clinical attached gingiva increased from 1.5mm to 4mm. The mean width of gained attached gingiva after surgery was 2.5mm. 4. The mean follow up period was 36.5 months. The longest follow up period was 50 months and the shortest follow up period was 22 months. 5. The result that obtained by surgery was stable during follow up period. Within the above results, root coverage with SCTG is an effective procedure to cover marginal tissue recession defect with long term stability.

• Archives of Reconstructive Microsurgery
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• 제19권1호
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• pp.56-60
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• 2010

Purpose: Breast reconstruction with abdominal flap has many advantages. However, it might cause abdominal complications such as bulging or hernia. SIEA (Superficial inferior epigastric artery) flap is the most advanced form of abdominal flap which has no adverse effect on abdominal fascia. We report 2 cases of breast reconstruction with SIEA flap with reference review. Methods: From Jun 2006 to Jan 2009, 110 patients underwent breast reconstruction with free abdominal flap. We tried to find the SIEA in every cases and adopted SIEP flap if the diameter was larger than 1mm and it had visible pulsation. 2 patients underwent breast reconstruction with SIEA flap. After design of abdominal flap SIEA was investigated with portable Doppler. SIEA was usually found 4-5 cm lateral to the midline. Flap was elevated with SIEA and SIEV to their maximal length at hiatus. Results: There were no complications, such as infection, hematoma, and necrosis of flap. In both cases, flaps survived completely with excellent vascularity and breast reconstruction was successful. In one case, there was skin necrosis of mastectomy flap, and it was healed by conservative management. Conclusion: With the SIEA flap, donor site morbidity can be minimized along with reduction of operation time. If there is reliable SIEA, SIEA flap would be the preferred skills. However, the limitation of the SIEA flap is difficulty in identifying the SIEA. The reason for less availability of the flap in Korea might include high prevalence of the Caesarian section scar and relatively higher level of the lower margin of the flap.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권3호
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• pp.120-126
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• 2013

Objectives: This study sought to elucidate the effect of autogenous tooth bone material by experimenting on minipig's maxillary sinus and performing histological and histomorphometric analyses. Materials and Methods: Five 18-24 month-old male minipigs were selected, and right maxillary sinuses were grafted with bone graft material made of their respective autogenous teeth extracted eight weeks earlier. The left sides were grafted with synthetic hydroxyapatite as control groups. All minipigs were sacrificed at 12 weeks after bone graft, which was known to be 1 sigma (${\sigma}$) period for pigs. Specimens were evaluated histologically under a light microscope after haematoxylin-eosin staining followed by semi-quantitative study via histomorphometric analysis. The ratio of new bone to total area was evaluated using digital software for calculation of area. Results: All specimens were available, except one on the right side (experimental group), which was missing during specimen preparation. This study demonstrated new bone at the periphery of the existing bone in both groups, showing evidence of bone remodeling, however, encroachment of new bone on the central part of the graft at the 1 ${\sigma}$ period was observed only in the autogenous tooth bone group (experimental group). Histomorphometric analysis showed more new bone formation in the experimental group compared to the control group. Although the difference was not statistically significant (P>0.05), the mean percentage area for new bone for the experimental and control groups were $57.19%{\pm}11.16%$ and $34.07%{\pm}13.09%$, respectively. Conclusion: The novel bone graft material using autogenous tooth is a good alternative to autogenous bone, comparable to autogenous bone, and outperforming synthetic hydroxyapatite bone graft materials in terms of bone regeneration capacity. Augmentation with autogenous tooth bone materials will reduce donor site morbidity without hampering the safety of the autogenous bone graft.

• Journal of Periodontal and Implant Science
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• 제30권2호
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• pp.277-287
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• 2000

For the regeneration of osseous defect on the furcation area, autogeneous bone graft has been primarily used. But it has the limitation of donor site, additive surgical operation etc. Recently anorganic xenogenic bone graft materials of removing all organic components are commonly used for the regeneration of periodontal defects. This study was the comparison of the effect on the regeneration with two types xenografts($Bio-oss^{(R)}$ and Ca-P thin coated Bovine bone powder) on the furcation involvement in Beagle dogs. After surgically induced chronic periodontitis in bifurcation area of premolar, $Bio-oss^{(R)}$ and Ca-P BBP were grafted on the osseous defects. Tissue blocks including defects with soft tissues were harvested following a four-& eight-week healing interval and prepared for histologic analysis. The results of this study were as follows: 1. $Bio-oss^{(R)}$ group: there were significant differences among the $Bio-oss^{?}$ group at 4weeks and 8weeks, but the control group had various appearances : new bone formation, resorption of graft materials by multinuclear giant cells, connective tissue cells intervention in the bone graft sites etc. 2. Ca-P BBP group: lots of new bone formation were observed but the arrangement of periodontal ligament was not completed at 4weeks. New bone were replaced mature bone and the periodontal ligaments showed the functional arrangement at 8weeks. 3. By reason of undergrowing the epithelium within the osseous defects, new bone formation was not happened in the upper area of bifurcation in $Bio-oss^{(R)}$ group. 4. In Ca-P BBP group, epithelial undergrowth was not seen and generally showed much more new bone formation. 5. Ca-P BBP group showed the osteocyte-like cells at the inner portion of the graft materials 6. Both groups were similar to resorptive appearances of graft materials, but Ca-P BBP group had the better effects of osteoconduction.

• 대한두개안면성형외과학회지
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• 제22권5호
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• pp.239-246
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• 2021

Background: Bone grafts can provide an optimal environment for permanent tooth to erupt and enhance the stability of the alveolar maxilla. Although autologous bone is an optimal source for osteogenesis, its inevitable donor site morbidity has led to active research on bone substitutes. This study was designed to evaluate the safety and feasibility of using biphasic calcium phosphate (BCP; Osteon) as a bone substitute in dogs. Methods: Bilateral third and fourth premolars of four 15-week-old mongrel dogs were used. All teeth were extracted except the third premolar of the right mandible, which was used as a control. After extraction of the premolars, each dog was administered BCP (Osteon), demineralized bone matrix (DBM; DBX), and no graft in the hollow sockets of the right fourth premolar, left fourth premolar, and left third premolar, respectively. Radiographs were taken at 2-week intervals to check for tooth eruption. After 8 weeks, each dog was sacrificed, and tooth and bone biopsies were performed to check for the presence of tooth and bone substitute particle remnants. Results: Four weeks after the operation, permanent tooth eruptions had started at all the extraction sites in each dog. Eight weeks after the operation, all teeth had normally erupted, and histological examination revealed BCP particles at the right fourth premolar. Conclusion: In all four dogs, no delay in the eruption of the teeth or shape disfigurement of permanent teeth was observed on gross inspection and radiologic evaluation. On histological examination, most of the BCP and DBM were replaced by new bone. Bone substitutes can be used as graft materials in patients with alveolar clefts.

• 한국지반환경공학회 논문집
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• 제13권9호
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• pp.53-59
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• 2012

본 연구에서는 Slow Release Substrate(SRS)로 사용되는 TBOS의 분해특성과 TBOS 분해생성물인 acetate와 butyrate를 적용한 탈염소화 효율을 파악하고자 하였다. 회분식 실험은 GC/FID를 이용하여 TCE 및 cis-dichloroethene(cis-DCE), 1-butanol, TBOS를 분석하였으며, acetate와 butylate는 HPLC를 이용하여 분석하였다. 혐기성 가수분해 반응을 통해 1M의 TBOS는 4M의 1-butanol로 전환 및 축적되었으며, 가수분해율은 $0.186{\mu}M/day$로 나타났다. 또한, 1-butanol은 퇴적토 내 토착균주에 의해 acetate와 butyrate로 분해되었다. 이 결과 TBOS는 자연에서의 탈염소화 공정에서 SRS로 사용하기에 적합한 것으로 판단된다. Acetate와 butyrate를 전자공여체로 적용한 TCE 탈염소화 반응은 초기 TCE 농도가 낮아짐에 따라 탈염소화 효율은 높아지는 것으로 나타났다. 또한, acetate를 적용한 탈염소화 반응의 1차 반응 상수가 butyrate를 적용한 경우보다 높게 나타났다. 이는 탈염소화 반응에서 Geobacter lovleyi의 기질친화도 및 생분해성, 그리고 다양한 기질에 대한 적응도의 영향으로 판단된다. 그러나 Geobacter lovleyi의 TCE 탈염 소화 반응에 따른 cis-DCE의 축적이 발생할 경우 Geobacter lovleyi의 탈염소화 능력이 감소하는 것으로 나타났다. 결론적으로 SRS는 Geobacter lovleyi를 이용한 TCE 탈염소화 공정 향상에 도움이 될 것이며, 이에 따라 발생되는 cis-DCE는 영가철 같은 환원성 금속이나 공존 가능한 탈염소화 미생물을 이용한 처리가 함께 필요할 것으로 판단된다.

• 한국미생물·생명공학회지
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• 제38권4호
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• pp.448-454
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• 2010

광양, 하남, 여천지역의 토양, 하천 및 해양 퇴적물 등을 이용하여, 난분해성 염소화합물인 PCE (perchloroethylene) 및 TCE(trichloroethylene)의 혐기성 탈염소화에 관련하는 미생물을 탐색하고 이들의 탈염소화 효율을 조사하였다. 혐기성 상호대사에 의한 탈염소화 효율을 조사하기위해 전자 공여체로 아세테이트를 사용하여 혐기성 회분식 실험을 실시 하였으며, 미생물 군집을 분석하기 위해, 분자생물학적인 기법인 16S rDNA의 DGGE 기법을 이용하였다. 그 결과, 4주간 집적배양을 통해 광양, 하남, 여천시료는 PCE와 TCE를 PCE 75% 이상, TCE 81% 이상 탈염소화하는 것으로 나타내며, 여천시료가 우수한 PCE/TCE탈염소화율을 보이고 있다(PCE 87.37%, TCE 84.46%). 또한, 전자 수용체에 따른 탈염소화 배양액의 미생물 다양성은 DGGE로 분석하였으며, 우점하는 미생물은 Clostridium sp., Desulfotomaculum sp.와 unculutured bacteria로 나타났다.