• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권3호
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• pp.229-236
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• 2009

Purpose: Some recent literatures report that it is possible to recover defected areas caused by enucleation of relatively large jaw cysts without using bone grafts. The aim was to find out whether spontaneous recovery of defected area with time occurred and what the contributing factors were. Materials and methods: In total, 194 patients were considered as patients. Out of these 194 patients, 74 patients who had no wound dehiscence and who were available for follow-up studies were selected. They were classified into two groups according to the size of radiolucent area in the preoperative panoramic radiographs: in one group, it was larger than $3{\times}4cm$, while in the other group, it was smaller than $3{\times}4cm$. Follow-up panoramic radiographs were taken immediately after the surgery, then after 3, 6, 9 and 12 months. On those radiographs, changes in size and density of the defected areas were observed using the Gray-level histogram of Adobe photoshop v7.0. Correlation between bone regeneration and factors such as the type and size of the cysts, age, sex, site of the cysts and systemic disease was evaluated using the General repeated measure and Mann-Whitney Test. Results: Analyses of panoramic radiographs showed that the recovery of radiopacity after 12 months was more than 97% on average in defected areas that were smaller than $3{\times}4cm$. in the defected areas that were larger than $3{\times}4cm$, considerable portion showed recovery of radiopacity. No statistically significant change was observed in bone density according to the type of cysts. Young patients under 20 years of age with highly active metabolism presented more significant bone regeneration than patients over 20 years of age. Bone regeneration was more hampered in patients who had medical disease, compared with patients who didn’t have any medical problem. No statistically significant change was seen in bone density according to sex. Changes in bone density according to the site of cysts such as maxilla, mandible, anterior or posterior region were not considered to be significant. Conclusion: Analyses of panoramic radiographs suggest that in approximately 12 months after the enucleation of cysts, clinically acceptable spontaneous bone regeneration can be observed even though normal bone graft procedures have not been applied.

• Journal of Periodontal and Implant Science
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• 제37권3호
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• pp.465-478
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• 2007

Various periodontal barrier membranes used in many clinical and experimental fields, and many recent studies of membranes have reported good results. To improve clinical results, selection of barrier membranes is an important factor. So, we need not only to evaluate various barrier mem-branes, but also to understand the property of barrier membranes appropriate to defect characteristics. For this purpose, this study reviewed available literature, evaluated comparable experimental models, and compared various barrier membranes. From above mentioned methods, the following conclusions are deduced. 1. In i-wall periodontal defect models, new bone formation showed a consistent result, almost 30% of the defect size. New cementum formations measured mostly 40% of the defect size, but showed more variations than new bone formations. This seems to be resulted form difference in experimental methods, so standardization in experimental methods is needed for future studies. 2. Application PLGA barrier membrane to periodontal defect demonstrated improved healing in new bone and new cementum. 3. There was a minimal periodontal regeneration with calcium sulfate barrier membrane only. But, there was better healing pattern in combination of calcium sulfate membrane with bone graft material, such as DFDBA, 4. There was no significant difference between the experimental group that used chitosan mem-brane only and the control group. But, in combination with bone graft material for space maintanence, periodontal regeneration was improved. Overall, Space maintenance is a critical factor for Guided tissue regeneration using barrier membranes. Also, a barrier membrane itself that has difficulty in maintaining space, achieved better result when used with graft material.

• 대한의용생체공학회:의공학회지
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• 제16권3호
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• pp.331-336
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• 1995

체내 매입후 경시적으로 분해되면서 재생골조직에 의해 치환되는 인공골복합체를 제조하고 복합체가 세포활성에 미치는 영향을 조사하였다. 복합체시편을 세포배양액에 넣고 1주일동안 $37^{\circ}C$에서 배양한 다음, 사람자궁경부암유래 HeLa S3세포와 쥐피하 L929세포를 복합체가 용해된 세포배양액에서 5일간 배양하여 세포성장율을 비교하여 세포특성을 조사하였다. 한편 HeLa S3세포를 배양중인 배양액에 ${Na_2}^{51}CrO_4$를 첨가하여 HeLa S3세포에 $^{51}Cr$를 표식한 다음, 용해된 $^{51}Cr$의 양을 $\gamma$-counter를 이용하여 측정하였다. 세포성장정도의 측정에서는 HeLa S3 세포 및 L929 세포 모두가 특이한 세포독성을 발견할 수 없었으며, 복합체가 용해된 세포배양액내의 표식된 HeLa S3 세포로 부터 용해된 $^{51}Cr$량을 측정한 결과, 세포활성을 저해하지 않은 것으로 관찰되었다.

• Journal of Periodontal and Implant Science
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• 제30권3호
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• pp.505-527
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• 2000

The 3 beagle dogs aged over one and half years and weighed 14 to 16 Kg were utilized in this study. Horizontal furcation defects were induced around 3rd, and 4th premolars bilaterally. BMP-4 in conjunction with EGF and BMP-4 only were applied in the right and left premolars respectively. 1 animal was sacrificed at 2nd week, 4th week, and 8th week, after regenerative surgery respectively. Semi-thin sections using glass-knife were stained with hematoxylin- eosin and trichrome for light microscopic study. The results were as follows : 1 . The long junctional epithelial downgrowth was observed in both area applied with BMP-4 and with BMP-4 and EGF at 2nd week after the surgery. 2 . The extensive regeneration of new bone and cementum was appeared at 4th week and the maturation of bone was observed at 8th week in both area applied with BMP-4 and with BMP-4 and EGF. 3 . The root ankylosis and resorption was presented along the exposed root surface at the coronal 1/3 of defect in the BMP-4 applied site, but it was not shown in the site applied with BMP-4 in conjunction with EGF at the 4th week. At 8th week, the root ankylosis was apparently appeared in the BMP-4 and EGF applied site as well as in the BMP-4 applied site. 4 . The periodontal ligament tissue including Sharpey's fiber inserted into cementum and alveolar bone, was formed along the exposed root surface in the area applied with BMP-4 only, but in the site applied with BMP-4 and EGF, the collagen fiber running parallel to the root surface without Sharpey's fiber, was observed in the periodontal ligament space at 4th and 8th week. Within the above results, BMP-4 had the remarkable capability to regenerate the periodontal tissue and EGF had possibility to prevent from the root ankylosis. Therefore, growth factors including BMP-4 and EGF may have the strong possibility to be utilized in the clinical periodontal treatments.

• Journal of Periodontal and Implant Science
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• 제26권3호
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• pp.771-778
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• 1996

The assessment of alveolar bone changes on dental radiographs to indicate progression of periodontal diseases or healing response to therapy is routine procedure. However, the diagnostic accuracy in detecting small alveolar bone changes is very limited. Recently, guided bone regeneration therapy is popular, but the quantification of new bone is somewhat difficult with conventional evaluation method. To quantificate the amount of new bone, various evaluating methods have been introduced including histomorphometry, radiomorphometry, biochemical analysis, X-ray probe microanalysis, scanning electron microscope backscatter method. In this study, guided bone regeneration using resorbable membrane with & without PDGF-BB is quatificated through histomorphmetry to evaluate the efficacy of histomorphometric analysis. 4 beagle dogs and 8 Sprague-Dawley rats were selected as experimental animals. In beagle dog experiment, $4{\times}4mm$ Class II defects were created in maxillary both second premolars, and biodegradable membrane containing PDGF-BB(experimental group) were covered over one defect, and same membrane without PDGF-BB(control group) were covered over the other defect. At 2 weeks, 5 weeks after surgery, each beagle dogs were sacrificed, and the tissues were treated by undecalcified fixation. In Sprague-Dawley rat experiment, 5mm round defect were created in temporal bone, the same membranes were covered on the defects. At 1 week, 2 weeks after surgery, each rats were sacrificed, and undecalcified fixation were taken. After grinding tissue specimen, we analyse them histomorphometrically using image analysis system. In beagle dog 2 weeks specimens, new bone formation area were $0.03123mm^2$ in experimental group,and $0.03012mm^2$ in control group. At 5 weeks specimens, $0.15324mm^2$ in experimental group, and $0.09123mm^2$ in control group. In Sprague-Dawley rat specimens, new bone fomation area were $0.20448mm^2$ in 1 week experimental group, $0.03604mm^2$ in 1 week control group. At 2 weeks specimens, $0.46349mm^2$ in experimental group, $0.17741mm^2$ in control group. The results indicated that histomorphometric analysis of new bone formation using image analysis system is very effective quantification method to evaluate the efficacy of treatment modalities.

• 대한소아치과학회지
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• 제34권3호
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• pp.473-480
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• 2007

함치성 낭종은 치관이 형성된 후 성상세망(stellate reticulum)의 변성으로 인하여 치관과 환원법랑질상피 사이에 유동물질이 축적되어 나타난다. 연령별로는 10대 또는 20대에서 발생율이 높고 거의 미맹출 치관과 관련되어 나타난다. 일반적으로 무증상이지만 낭이 크거나 염증이 동반된 경우 종창과 통증을 유발한다. 함치성 낭종은 방사선 검사 시 미맹출 치아의 치관을 둘러싸는 경계가 명확한 단방성의 방사선 투과성 병소로 나타나며, 인접치의 변위나 치근흡수가 관찰되기도 한다. 함치성 낭종의 치료 목적은 비정상조직을 완전히 제거하되 낭종내 전위된 치아를 가급적 보존하여 맹출을 유도하고 악궁 내에서 기능할 수 있도록 하는 것이며, 제거술식으로는 적출술과 조대술이 널리 이용되고 있다. 조대술은 낭벽의 일부분을 제거하여 구강점막과 연결시켜 주는 술식으로 낭내의 압력이 감소함에 따라 결손부 골 재생이 일어나며 낭벽은 정상적인 점막으로 변하게 된다. 특히 이는 인접 주요 구조물을 보호할 수 있고, 맹출 공간이 충분하다면 낭에 포함된 영구치의 맹출을 유도할 수 있는 가장 보존적인 치료이다. 본 증례들에서 임상 및 방사선학적 검사소견상 함치성 낭종으로 판단하고 조대술을 이용하여 낭종을 제거하였으며 전이된 치아를 보존하고 자연맹출을 유도하여 양호한 결과를 얻었기에 보고하는 바이다.

• 대한소아치과학회지
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• 제44권1호
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• pp.108-115
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• 2017

매복치의 치료방법으로 교정적 견인, 발치 후 임플란트, 자가치아이식 등 다양한 치료 방법이 있다. 그 중에서도 자가치아이식은 성장하는 환자들에게서 이식치 고유의 치주인대세포의 보존 및 치조골 성장이 가능하다는 점에서 좋은 치료방법이라고 생각된다. 이 증례에서는 성장중인 청소년의 이소 매복 치아를 자가치아이식으로 치료한 두 개의 증례를 소개하고자 한다. 첫 번째 증례에서 이소 매복된 좌측 하악 제2소구치를 발거 후 정위치로 자가치아이식하였고 혈소판 농축 피브린(PRF)과 mineral trioxide aggregate (MTA)를 사용하여 재생 근관 치료를 하였다. 석회화 치성낭으로 인해 이소매복된 좌측 하악 제2대구치를 지닌 두 번째 증례에서 병소의 적출술을 시행하였다. Obturator를 3개월 간 장착하여 매복치아의 자발적 맹출을 기대하였으나 맹출 양상이 없어 자가치아이식한 후 MTA를 이용한 근관치료를 하였다. 두 증례 모두 자가치아이식술로 이소매복치를 간단하고 빠르게 치료하였다. 성장하는 환자에게서 이소매복치의 자가치아 이식술은 임플란트나 보철물 수복 대신 좋은 치료 방법이 될 것이다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제33권2호
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• pp.112-119
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• 2011

Purpose: Collagen membranes are used extensively as bioabsorbable barriers in guided bone regeneration. However, collagen has different effects on tissue restoration depending on the type, structure, degree of cross-linking and chemical treatment. The purpose of this study was to evaluate the inflammatory reaction, bone formation, and degradation of dehydrothermal treated porcine type I atelocollagen (CollaGuide$^{(R)}$) compared to of the non-crosslinked porcine type I, III collagen (BioGide$^{(R)}$) and the glutaldehyde cross-linked bovine type I collagen (BioMend$^{(R)}$) in surgically created bone defects in rat mandible. Methods: Bone defect model was based upon 3 mm sized full-thickness transcortical bone defects in the mandibular ramus of Sprague-Dawley rats. The defects were covered bucolingually with CollaGuide$^{(R)}$, BioMend$^{(R)}$, or BioGide$^{(R)}$ (n=12). For control, the defects were not covered by any membrane. Lymphocyte, multinucleated giant cell infiltration, bone formation over the defect area and membrane absorption were evaluated at 4 weeks postimplantation. For comparison of the membrane effect over the bone augmentation, rats received a bone graft plus different covering of membrane. A $3{\times}4$ mm sized block graft was harvested from the mandibular angle and was laid and stabilized with a microscrew on the naturally existing curvature of mandibular inferior border. After 10 weeks postimplantation, same histologic analysis were done. Results: In the defect model at 4 weeks post-implantation, the amount of new bone formed in defects was similar for all types of membrane. Bio-Gide$^{(R)}$ membranes induced significantly greater inflammatory response and membrane resorption than other two membranes; characterized by lymphocytes and multinucleated giant cells. At 10 weeks postoperatively, all membranes were completely resorbed. Conclusion: Dehydrotheramal treated cross-linked collagen was safe and effective in guiding bone regeneration in alveolar ridge defects and bone augmentation in rats, similar to BioGide$^{(R)}$ and BioMend$^{(R)}$, thus, could be clinically useful.

• Journal of Periodontal and Implant Science
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• 제33권1호
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• pp.13-26
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• 2003

Periodontal regeneration therapy with bone-substituting materials has gained favorable clinical efficacy by enhancing osseous regeneration in periodontal bony defect. As bone-substituting materials, bone powder, calcium phosphate ceramic, modified forms of hydroxyapatite, and hard tissue replacement polymer have demonstrated their periodontal bony regenerative potency. Bone-substituting materials should fulfill several requirements such as biocompatibility, osteogenecity, malleability, biodegradability. The purpose of this study was to investigate biocompatibility, osteo-conduction capacity and biodegradability of $Na_2O$, $K_2O$ added calcium metaphosphate(CMP). Beta CMP was obtained by thermal treatment of anhydrous $Ca_2(H_2PO_4)_2$. $Na_2O$ and $K_2O$ were added to CMP. The change of weight of pure CMP, $Na_2O$-CMP, and $K_2O$-CMP in Tris-buffer solution and simulated body fluid for 30 days was measured. Twenty four Newzealand white rabbits were used in negative control, positive control(Bio-Oss), pure CMP group, 5% $Na_2$-CMP group, 10% $Na_2O$-CMP goup, and 5% $K_2O$-CMP group. In each group, graft materials were placed in right and left parietal bone defects(diameter 10mm) of rabbit. The animals were sacrificed at 3 months and 6 months after implantation of the graft materials. Degree of biodegradability of $K_2O$ or $Na_2O$ added CMP was greater than that of pure CMP in experimental condition. All experimental sites were healed with no clinical evidence of inflammatory response to all CMP implants. Histologic observations revealed that all CMP grafts were very biocompatible and osseous conductive, and that in $K_2O$-CMP or $Na_2O$-CMP implanted sites, there was biodegradable pattern, and that in site of new bone formation, there was no significant difference between all CMP group and DPBB(Bio-Oss) group. From this result, it was suggested that all experimental CMP group graft materials were able to use as an available bone substitution.

• 대한소아치과학회지
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• 제41권1호
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• pp.85-92
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• 2014

함치성 낭종은 미맹출치의 치관을 둘러싸는 퇴축법랑상피로부터 기원한다. 대부분의 함치성 낭은 적출술 또는 조대술로 치료된다. 조대술을 통해 낭 내부의 압력이 감소하고 골의 재생이 일어나면서 낭벽은 정상적인 점막으로 변하게 된다. 조대술은 적출술에 비해 인접 주요 구조물을 보호할 수 있다는 장점이 있다. 본 증례는 5세와 11세 남아의 상악 정중 과잉치와 치수 치료된 하악 유구치 부위에서 발견된 각각의 함치성 낭종을 치료한 증례로 모두 낭의 크기가 2개 이상의 인접 영구치의 변위를 발생시킬 정도로 크기가 매우 컸다. 환자의 나이가 어리고 낭의 크기가 커서 조대술을 이용하여 치료하였고 그 결과 변위된 인접 영구치의 맹출 방향이 개선되고 방사선투과상의 크기가 점점 감소하는 것으로 관찰되었다. 본 증례와 같이 크기가 매우 큰 함치성 낭의 경우에서 조대술을 이용하여 치료할 경우 위치가 변이된 인접치아를 보존하고 영구치의 자연 맹출을 유도할 수 있는 양호한 결과가 예상되기에 보고하는 바이다.