• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권5호
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• pp.366-374
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• 2010

Introduction: This study evaluated the capability of silk fibroin (SF) and recombinant human bone morphogenetic protein-2 loaded SF (SF-BMP) as a bone defect replacement matrix when grafted in a calvarial bone defect of rats in vivo. Materials and Methods: A total 70 calvarial critical size defects (5.0 mm in diameter) made on 35 adult female Sprague-Dawley rats were used in this study. The defects were transplanted with (1) rhBMP-2 loaded silk fibroin graft (SF-BMP: 0.8+$10\;{\mu}g$), (2) Silk fibroin (SF: $10\;{\mu}g$), and (3) no graft material (Raw). The samples were evaluated with soft x-rays, alkaline phosphatase activity, calcium/phosphate quantification, histological and histomorphometric analysis at postoperative 4 and 8 weeks. Results: The SF-BMP group ($48.86{\pm}14.92%$) had a significantly higher mean percentage bone area than the SF group ($24.96{\pm}11.01%$) at postoperative 4 weeks.(P<0.05) In addition, the SF-BMP group ($40.01{\pm}12.43%$) had a higher % bone area at postoperative 8 weeks than the SF group ($33.26{\pm}5.15%$). The mean ratio of gray scale levels to the host bone showed that the SF-BMP group ($0.67{\pm}0.08$) had a higher mean ratio level than the SF group ($0.61{\pm}0.09$) at postoperative 8 weeks. These differences were not statistically significant.(P=0.168 and P=0.243, respectively) The ratio of the calcium and phosphate contents of the SF-BMP ($0.93{\pm}0.22$) group was lower than that of the SF ($1.90{\pm}1.42$) group at postoperative 4 weeks. However, the SF-BMP group ($0.75{\pm}0.31$) had a higher Ca/$PO_4$ ratio than the SF ($0.68{\pm}0.04$) at postoperative 8 weeks. These differences were not statistically significant.(P=0.126 and P=0.627, respectively) For the bone-specific alkaline phosphatase (ALP) activity, which is recognized as a reliable indicator of the osteoblast function, the SF-BMP ($23.71{\pm}8.60\;U/L$) groups had a significantly higher value than the SF group ($12.65{\pm}6.47\;U/L$) at postoperative 4 weeks.(P<0.05) At postoperative 8 weeks, the SF-BMP ($21.65{\pm}10.02\;U/L$) group had a lower bone-specific ALP activity than the SF group ($16.72{\pm}7.35\;U/L$). This difference was not statistically significant.(P=0.263) For the histological evaluation, the SF-BMP group revealed less inflammation, lower foreign body reactions and higher bone healing than the SF group at postoperative 4 and 8 weeks. The SF group revealed more foreign body reactions at postoperative 4 weeks. However, this immunogenic reaction decreased and the remnant of grafted material was observed at postoperative 8 weeks. For histomorphometric analysis, the SF-BMP group had a significantly longer bone length to total length ratio than those of the SF group at postoperative 4 and 8 weeks.(P<0.05) Conclusion: The rhBMP-2 loaded silk fibroin graft revealed fewer immunoreactions and inflammation as well as more new bone formation than the pure silk fibroin graft. Therefore, silk fibroin may be a candidate scaffold for tissue engineered bone regeneration.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권4호
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• pp.293-298
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• 2010

Purpose: The objective of the present study was to determine the capability of electrospun silk fibroin as a biomaterial template for bone formation when mixed with nano-hydoxyapatite in vivo. Materials and Methods: Ten New Zealand white rabbits were used for this study and bilateral round shaped defects were formed in the parietal bone (diameter: 8.0 mm). The electrospun silk fibroin was coated by nano-hydroxyapatite and grafted into the right parietal bone (experimental group). The left side (control group) did not receive a graft. The animals were sacrificed at 6 weeks and 12 weeks, humanly. The microcomputerized tomogram (${\mu}CT$) was taken for each specimen. Subsequently, they were undergone decalcification and stained for the histological analysis. Results: The average value of all measured variables was higher in the experimental group than in the control at 6 weeks after the operation. BMC in the experimental group at 6 weeks after operation was $48.94{\pm}19.25$ and that in the control was $26.17{\pm}16.40$ (P = 0.027). BMD in the experimental group at 6 weeks after operation was $324.59{\pm}165.24$ and that in the control was $173.03{\pm}120.30$ (P = 0.044). TMC in the experimental group at 6 weeks after operation was $19.50{\pm}6.00$ and that in the control was $10.52{\pm}6.20$ (P = 0.011). TMD in the experimental group at 6 weeks after operation was $508.88{\pm}297.57$ and that in the control was $273.54{\pm}175.91$ (P = 0.06). Gross image of both groups showed higher calcification area at 12 weeks than them in 6 weeks. The average value of ${\mu}CT$ analysis was higher at 12 weeks than that in 6 weeks in both groups. BMC in the experimental group at 12 weeks after operation was $51.21{\pm}8.81$ and that in the control was $33.47{\pm}11.13$ (P = 0.010). BMD in the experimental group at 12 weeks after operation was $323.39{\pm}21.54$ and that in the control was $197.75{\pm}76.23$ (P = 0.012). TMC in the experimental group at 12 weeks after operation was $21.44{\pm}5.30$ and that in the control was $13.31{\pm}4.17$ (P = 0.008). TMD in the experimental group at 12 weeks after operation was $524.47{\pm}19.37$ and that in the control was $299.60{\pm}136.20$ (P = 0.016). Conclusion: The rabbit calvarial defect could be successfully repaired by electrospun silk nano-fiber combined with nano-hydroxyapatite.

• 대한소아치과학회지
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• 제34권1호
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• pp.140-149
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• 2007

치조파열 및 구개열과 같은 선천성 기형은 이환된 환자에게 기능적, 심미적으로 많은 문제점을 야기하므로 정상으로 회복시켜 주는 것은 중요한 문제이다. 장기간 방치될 경우 영양장애, 구강위생 불량, 호흡기 감염, 언어 장애, 악안면 변형, 그리고 정신적인 문제 등이 복합적으로 발생할 수 있다. 따라서 구순구개열 환자의 치료는 여러 전문 치료 분야의 복합적 인 접근이 필요하다. 골이식은 구순구개열 환자에 있어 중요한 치과치료 단계이다. 치아의 맹출과 치열의 안정화를 위해 치열궁은 골결손이 없이 완전해져야 한다. 또한 치열궁의 파열이 있는 부위로는 정상적인 교정적 치아이동이 곤란하다. 따라서 구순구개열 환자에 있어 골이식은 광범위하게 적용되고 있는 외과적 술식이다. 치조골을 이식함으로써 치조열은 안정화되고, 견치 또는 절치가 이식부위로 이동할 수 있게 된다. 그리고 골 이식 후, 교정을 통해 치조열 부위의 공간을 폐쇄함으로써 보철치료 없이 치열을 재형성 할 수 있다. 골이식술에는 다양한 이식재료가 사용되었다. 자가골을 이식할 경우 장골이 가장 선호되며, 그밖에 경골, 늑골, 두개골, 하악골을 이용하기도 한다. 그리고 골이식은 골이식 시기에 따라 일차골이식, 조기 이차골이식, 이차골이식, 만기 이차골이식으로 구분할 수 있다. 이차골이식은 혼합치열기 말경에 시행되는 것을 말하며 가장 좋은 것으로 받아들여지고 있다. 영구 견치가 맹출되기 전에 이차골이식을 시행하면 인접치아의 맹출과 보존에 도움이 된다. 본 증례에서는 치조구개파열 환자의 장골에서 골을 채취하여 골 이식을 시행한 후, 골이 채워진 이식 부위에 인접 치아가 성공적으로 이동하거나 치축이 개선되고 교정치료를 통해 치열궁 배열의 만족스러운 결과를 얻었기에 이를 보고하는 바이다.

• Journal of Periodontal and Implant Science
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• 제30권4호
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• pp.835-852
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• 2000

The ultimate goal of periodontal therapy is the regeneration of periodontal tissue and repair of function. For more than a decade there have been many efforts to develop materials and methods of treatment to promote periodontal wound healing. Recently many efforts are concentrated on the regeneration potential of material used in oriental medicine. In some in vitro and in vivo experiments, there have been many evidences that these materials have an effect on bone regeneration. The purpose of this study was to evaluate histologically and radiologically in Sprague-Dawley rats the effects of safflower seed extracts on the regeneration of the calvarial defects surgically produced. So in this study, the critical size defects were surgically produced in the calvarial bone of 30 Sprague-Dawley rats using the 8mm trephine bur. The safflower seed extract was applied into the defect of each rat in experimental group, whereas nothing was applied into the defect of each rat in control group. Rats were sacrificed at 2, 4, 8 weeks following operation and histomorphometric and radiodensitometric analysis were performed. 1. The newly formed bone length was $102.91{\pm}22.05$, $178.29{\pm}24.40$ at 2 week in the each control, experimental group, $130.95{\pm}39.24$, $242.62{\pm}50.33$ at 4 week and $181.53{\pm}76.35$, $240.36{\pm}22.00$ at 8 week($unit,{\mu}m$). In the 2, 4 week, there were statistically significant difference between control and experimental group(P<0.05). 2. The newly formed bone area was $2962.06{\pm}1284.48$, $10648.35{\pm}1284.48$ at 2 week, $5103.25{\pm}1375.88$, $9706.78{\pm}1481.81$ at 4 week, $8046.02{\pm}818.99$, $12057.06{\pm}740.47$ at 8 week($unit,{\mu}m^2$). In every week, there were statistically significant difference between control and experimental group(P<0.05). 3. The radiopacity was $14.26{\pm}.33$, $25.47{\pm}4.33$ at 2 week, $20.06{\pm}9.07$, $26.61{\pm}2.78$ at 4 week, $22.99{\pm}3.76$, $27.29{\pm}1.54$ at 8 week(unit, %). In the 2 week, there was statistically significant difference between control and experimental group(P<0.05). In conclusion, the results of the present study suggest that safflower seed extract initially has an effect on the newly formed bone area, length and radiopacity when it is applied to the calvarial defect of Sprague - Dawley rat. Then. the material has an effect on newly formed bone area and length.

• Journal of Periodontal and Implant Science
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• 제30권4호
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• pp.851-870
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• 2000

The major goals of periodontal therapy is the functional regeneration of periodontal supporting structures already destructed by periodontal disease as well as the reduction of signs and symptoms of progressive periodontal disease. There have been many efforts to develop materials and therapeutic methods to promote periodontal wound healing. There have been increasing interest on the chitosan made by chitin. Chitin is second only to cellulose as the most abundant natural biopolymer. It is a structural component of the exoskeleton of invertebrates(e.g., shrimp, crabs, lobsters), of the cell wall of fungi, and of the cuticle of insects. Chitosan is a derivative of chitin made by deacetylation of side chains. Many experiments using chitosan in various animal models have proven its beneficial effects. The aim of this study is to evaluate the osteogenesis of chitosan on the calvarial critical size defect in Sprague Dawley rats. An 8 mm surgical defect was produced with a trephine bur in the area of the midsagittal suture. The rats were divided into two groups: Untreated control group versus experimental group with 50mg of soluble chitosan gel. The animals were sacrificed at 2, 4 and 8 weeks after surgical procedure. The specimens were examined by histologic, histomorphometric and radiodensitometric analyses. The results are as follows: 1. The length of newly formed bone in the defects was $102.91{\pm}25.46{\mu}m$, $219.46{\pm}97.81{\mu}m$ at the 2 weeks, $130.95{\pm}39.24{\mu}m$, $212.39{\pm}89.22{\mu}m$ at the 4 weeks, $181.53{\pm}76.35{\mu}m$ and $257.12{\pm}51.22{\mu}m$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. But, there was no statistically significant difference between the two groups. 2. The area of newly formed bone in the defects was $2962.06{\pm}1284.48{\mu}m^2$, $5194.88{\pm}1247.88{\mu}m^2$ at the 2 weeks, $5103.25{\pm}1375.88{\mu}m^2$, $7751.43{\pm}2228.20{\mu}m^2$ at the 4 weeks and $8046.20{\pm}818.99{\mu}m^2$, $15578.57{\pm}5606.55{\mu}m^2$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. The experimental group showed statistically significant difference to the control group at the 2 and 8 weeks. 3. The density of newly formed bone in the defects was $14.26{\pm}6.33%$, $27.91{\pm}6.65%$ at the 2 weeks, $20.06{\pm}9.07%$, $27.86{\pm}8.20%$ at the 4 weeks and $22.99{\pm}3.76%$, $32.17{\pm}6.38%$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. The experimental group showed statistically significant difference to the control group at the 2 and 8 weeks. These results suggest that the use of chitosan on the calvarial defects in rats has significant effect on the regeneration of bone tissue in itself

• Journal of Periodontal and Implant Science
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• 제35권4호
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• pp.1019-1037
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• 2005

The major goals of periodontal therapy are the functional regeneration of periodontal supporting structures already destructed by periodontal disease as well as the reduction of signs and symptoms of progressive periodontal disease. There have been many efforts to develop materials and therapeutic methods to promote periodontal wound healing. There have been increasing interest on the chitosan made by chtin. Chitosan is a derivative of chitin made by deacetylation of side chains. Chitosan has been widely studied as bone substitution and membrane material in periodontology. Many experiments using chitosan in various animal models have proven its beneficial effects. Tetracycline has been considered for use in the treatment of chronic periodontal disease and gingivitis. The aim of this study is to evlauate the osteogenesis of tetracycline blended chitosan membranes on the calvarial critical size defect in Sprague Dawley rats. An 8mm surgical defect was produced with a trephine bur in the area of the midsagittal suture. The rats were divided into five groups: Untreated control group versus four experimental group. Four types of membranes were made and comparative study was been done. Two types of non-woven membranes were made by immersing non-woven chitosan into either the tetracycline solution or chitosan-tetracycline solution. Other two types of sponge membranes were fabricated by immersing chitosan sponge into the tetracycline solution, and subsequent freeze-drying. The animals were sacrificed at 2 and 8 weeks after surgical procedure. The specimens were examined by histologic analyses. The results are as follows: 1. Clinically the use of tetracycline blended chitosan membrane showed great healing capacity. 2. The new bone formations of all the experimental group, non-woven and sponge type membranes were greater than those of control group. But, there was no significant difference between the experimental groups. 3. Resorption of chitosan membranes were not shown in any groups at 2 weeks and 8 weeks. These results suggest that the use of tetracycline blended chitosan membrane on the calvarial defects in rats has significant effect on the regeneration of bone tissue in itself. And it implicate that tetracycline blended chitosan membrane might be useful for guided tissue regeneration.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권5호
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• pp.365-374
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• 2009

Purpose : This research evaluates the effect of the use of absorbable membrane barrier with deproteinized bovine bone (Bio-$Oss^{(R)}$, Switzerland) on bone healing in surgically created critical-sized defects in rat calvaria. Materials and Methods : Two standardized transosseous circular calvarial defects (5 mm in diameter) are made in each calvarium of 30 rats. These rats are divided into negative control group(n=15), positive control group(n=15) and two experimental groups(n=15). In the negative control group, defects are only filled with blood clots. In the positive control group, defects are filled with autogenous bone obtained from calvarium; in the experimental group 1, defects are filled with deproteinized bovine bone; and in the experimental group 2, defects are filled with deproteinized bovine bone with absorbable membrane. At the postoperative 1 week, 3 weeks. and 6 weeks, clinical. histologic and histomorphometric evaluations of the defects are performed. Results : 1. The grafted bone without membrane in the calvarial bone defect was scattered but, the grafted bone with membrane was stable. 2. $BioMesh^{(R)}$ membrane was absorbed beginning at 3 weeks, and was absorbed considerably at 6 weeks while maintaining the structural form of the membrane. 3. The use of membrane blocked soft tissue invasion. 4. In histomorphometric analysis. it showed the greatest amount of new bone formation in the positive control group. The amount of new bone formation was greater in the experimental group 2 than experimental group 1. At 6 weeks. the amount of new bone formation was greater in the positive control group than experimental group l(p<0.005). Conclusion : These results suggest that membrane increase the stability of grafted bone and protects from soft tissue invasion, and the use of the membrane may promote new bone formation in deproteinized bovine bone graft area.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1982년도 제16차 학술대회연제순서 및 초록
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• pp.17.2-19
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• 1982

중이 병변에 관한 수술적 처치는 그 병소 부위가 고막에 국한되어 있거나 중이 강 전벽부 및 내면부의 경우 수술시야가 좋아서 그 처치가 용이하며 술후 청력개선 및 치유경과도 만족할만하며 다양한 수술적 처치방법이 연구되어 널리 시행되고 있다. 그러나 아직도 중이강 후벽이나 상고실에 있는 병소의 처리방법에 대하여서 많은 문제점을 노출시키고 있으며 그 이유로서는 첫째 수술 시야의 장애, 둘째 안면신경 손상의 위험, 셋째 등골 주변부 병소 조작에 의한 외임프의 유출 및 미로 손상의 위험, 넷째 상고실 부위가 너무 협소하여 수술시 병변 확인이 힘든 경우등을 들수 있다. 특히 Staged operation (단계수술)과 Intact Canal Wall Typanoplasty(외청도 보존형 유양동 삭개술)이 소개된 이후로는 더욱더 중이강후벽에 대한 해부학적 지식이 더욱 절실하게 되었으며, 두개골의 인종적 차이를 감안 할때 한국인에 대한 중이강 후벽의 구조적 연구를 필요로 하게 되었다. 중이강의 후벽(유돌벽)은 Reichert's 연골에서 기원되며 제 2새궁(Second branchial arch)에서 발생되며 이 후벽의 구조물중 Sinus tympani는 이관의 내피와(endothelial pouch) 중 후낭 (Saccus posticus) 에서 함기화 (pneumatization)된 중이봉소로서 이부위 병변의 제거가 중이수술시 중요한 의의를 갖는 이유는 만성중이염에 의해 염증성반응이 오래 지속되면 비 후된 점막에 의해 Sinus tympani가 밀폐되고, 지속되는 자극에 의해 주로 안면신경관의 골성부와 등골 및 후반규관(Posterior Semicircular Canal)의 골성부에 육아조직을 형성하기 쉬울뿐더러 진주종에 의해 이 부위의 침식성 파괴를 이르켜 각각의 조직을 노출시킴으로 인해 중요한 합병증을 초래하기 쉬우며 수술로 인한 중대한 후유증이 병발하기 쉬운 곳이므로 임상면에서 중요하다. 그러므로 오래 전부터 이곳 병변의 안전한 제거를 위해 여러사람의 끊임없는 연구가 있었다. Amjad (1968), Donaldson (1970)등은 각각 24개, 20개의 측두골 계측을 실시하여 Sinus tympani의 형태 해부하적 구조에 대하여 연구한 결과 Sinus tympani의 크기와 모양은 여러형태로 변형이 많으며, 특히 주위 중요한 조직과 연관성이 많은 Sinus tympani의 가장 은밀한 심부 (Deepest portion)는 거의 대부분 후부로 신전되는 경우의 변형이 많아 주위조직의 손상없이 Sinus tympani의 병변을 제거하기 힘든 형태라는 결론을 내리고 이곳의 수술적 처리에서 발생 할 수 있는 여러 문제점을 지적하였다. Jako (1965) 등은 Sinus tympani병소의 안전한 제거를 위해 Sinus tympani를 확인할 수 있는 광학거울 (Fine-grade optical mirror)을 이 부위에 넣고 반사시야에서 수술적 처치를 시행할 것을 주장했으나, 수술시의 출혈등에 의한 명료시야의 확보에 문제점이 있어 널리 시행되지 않았다. Saito(1971)등은 Sinus tympani의 접근방법으로서 종래의 중이강내에서 접근방식 (Tympani approach) 보다 유양동을 통한 접근(mastoid approach)이 보다 편리하고 확실한 방법일 것이라는 생각으로 42개의 측두골에 대한 미세해부학적 계측을 실시하였다. 그러나 연구결과에서 그는 Sinus tympani의 상부는 안면신경과 지나치게 가까운 거리에 있어 접근이 용이하지 않았고 후부는 이낭(Otic capsule)에서 발생한 중치밀골(Hard compact bone)로 되어 있으며 안면신경 과 후반규관 사이가 협소하여 수술시 micro-drill burr로서 제거하기가 용이치 않다는 사실을 밝혀내고 mastoid approach로는 Sinus tympani 접근이 힘들다는 결론을 지었다. Goodhill (1973)등은 술자의 위치에서 수술의 전 과정을 시행하는 보편적인 방법에서는 Sinus tympani의 병변제거가 힘들므로 술자의 위치의 반대방향에서 현미경적 시야를 확보함으로써 은밀한 부위의 병변제거가 용이하다는 Circumferential approach 방법을 주장하였으나 수술부위의 감염성이 높다는 점이 문제점으로 지적되었다. 한편 Sinus tympani와 함께 수술시 문제점이 될 수 있는 후벽구조의 일부인 facial recess는 내피와(Endothelial pouch)중 상낭(Saccus superior)과 내낭(Saccus medius)에서 발생한다. 최근 Intact Canal Wall Tympanoplasty에 대한 활발한 연구가 진행되고 이에 따라 단계수술을 시행하는 빈도가 증가함에 따라 이 수술의 성공여부에 관건이 되는 중이강과 유양동의 통기(Ventilation)를 유지시키기 위해서 facial recess에 대한 많은 연구가 있었다. Sheehy(1967)등은 facial recess를 개방하는 이유로서는 첫째 facial recess의 병변이 제거되고 둘째 골성고실륜(bony annulus)을 손상시키지 않고 난원창과 중이강 후부를 노출시킬 수 있으며 셋째 atticotomy를 시행치 않고도 안면신경의 일부와 상고실 (epitympsnum) 을 노출시키는 것이 용이하며 넷째 수술후 유양동의 통기를 유지시키는 Posterior tympanotony를 주장하였다. 중이수술을 성공적으로 시행하려면 중이강후벽의 정확한 형태해부학적 구조를 이해하고 이 부위 병변을 제거하는 용이한 접근방법에 대한 술자의 고도의 기술이 요구되므로 이에 저자는 다양한 해부학적 변형에 대하여 연구할 필요성을 느껴 Sinus tympani와 facial recess를 중심으로 한국인 정상성인의 중이강후벽의 크기와 모양을 계측하였다. 연구대상은 측두골 35개 대상으로 능형융기 (pyramidal eminence) 안면신경, 등골 및 반규관등을 중심으로 주변부 구조의 계측을 시도하였다. 계측의 정확성과 정밀성을 높이기 위해 각각의 은밀한 부위에 Elastic impression material 인 PERMLASTIC$^{(R)}$ (type 1 Polysul_fide base class 2 Regular body)을 삽입한뒤 1 시간 경과 후 그 주위에 복잡한 구조가 양각된 주형물을 분리하여 계측을 실시하였다. 각부위와의 거리는 1/20mm까지 측정가능한 부척이 있는 척도계인 Matui$^{(R)}$ caliper를 사용하여 수술현미경하에서 시행하여 다음과 같은 결과를 얻었다. 1) 능형융기의 전부에서 Sinus tympani의 후부 및 Sinus tympani의 후부와 상부의 최대 신전 거리는 각각 2.54(1.05~5.40)mm, 3.22(1.25~7.45)mm, 0.67(0.40~l.75)mm 였다. 2) Sinus tympani는 상하경계가 난원창하부에서 정원창상부인 경우가 29예 (82.9 %)로 가장 많았다. 3 ) Sinus tympani의 후부는 심부(Deepest portion)가 ponticulus와 subiculum 사이인 경우가 22예(62.9 %)로 가장 많았다. 4) Facial recess의 침골와(Fossa incudis)로부터 하고실(hypotympanum)까지의 사선거리와 난원창과 정원창사이 중앙부에서의 횡선거리 및 침골와에서의 횡선거리는 각각 8.13 (7.90~9.55)mm 3.00 (2.85~3.45)mm 1,81 (1.40~2.15)mm 였다. 5) 안면신경관의 골결손 (bony dehiscence)은 5예 (14.3 %)에서 있었다. 6) 등골족판(footplate)의 전후거리 및 시상돌기(Cochleariform process)와 정원창까지의 거리는 각각 2.98(2.85~3.05)mm, 1.42 (1.35~l.55)mm, 1.85(1.45~2.10)mm 였다.