• Journal of Periodontal and Implant Science
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• 제31권1호
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• pp.41-57
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• 2001

It is well known that the apposition of bone at implant surface would be influenced by the microstructure of titanium implants. The purpose of this study was to compare bone healing around the screw-shaped titanium implant with three different surface topographies in the canine mandibles by histological and biomechanical evaluation. All mandibular premolars of six mongrel dogs were extracted and implants were placed one month later. The pure titanium implants had different surface topographies: smooth and machined ($Steri-OSS^{(R)}$: Group II); sandblasted and acid-etched ($ITI^{(R)}$, SLA: Group III) surface. The fluorescent dyes were injected on the 2nd (calcein), 4th (oxytetracycline HCI) and 12th (alizarin red) weeks of healing. Dogs were sacrificed at 4 and 12 weeks after implantation. The decalcified and undecalcified specimens were prepared for histological and histo-metrical evaluation of implant-bone contact. Some specimens at 12 weeks after implantation were used for removal torque testing. Histologically, direct bone apposition to implant surface was found in all of the treated groups. More mature and dense bone was observed at the implant-bone interface at 12 weeks than that at 4 weeks after implantation. Under the fluorescent microscope, thick regular green fluorescent lines which mean early bone apposition were observed at the implant-bone interface in Group III, while yellow and red fluorescent areas were found at the implant-bone interface in Group I and II. The average implant-bone contact ratios at 4 weeks of healing were 54.3% in Group I, 57.7% in Group II and 66.2% in Group III. In Group I, implant-bone contact ratio was significantly lower than Group II and III(p<0.05). The average implant-to-bone contact ratios at 12 weeks after implantation were 64.3% in Group I, 66.7% in Group II and 71.2% in Group III. There was no significant difference among the three groups. In Group I and II, the implant-bone contact ratio at 12 weeks increased significantly in comparison to ratio at 4 weeks(p<0.05). The removal torque values at 12 weeks after implantation were 90.9 Ncm in Group I, 81.6 Ncm in Group II and 77.1 Ncm in Group III, which were significantly different(p<0.05). These results suggest that bone healing begin earlier and be better around the surface-treated implants compared to the smooth surface implants. The sandblasted and acid-etched implants showed the most favorable bone response among the three groups during the early healing stage and could reduce the waiting period prior to implant loading.

• 한국환경보건학회지
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• 제32권4호
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• pp.342-352
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• 2006

The experiments was undertaken to evaluate the effects of herbal medicine, Dalsaengtang, in pregnant rats and fetuses. Female Sprague-Dawley rats were orally administered with the Dalsaengtang at dose of 5 mg/kg/day for 20 days. Pregnant rats were sacrificed at 20th day of gestation, and observed internal and reproductive organs. Approximately live fetuses in the 20th day of gestation were randomly selected and fixed in 95% ethanol. To observe skeletal malformations, fetuses were stained with alcian blue and alizarin red S. Maternal body weight of dalsaengtang treated group has a tendency to increase compared to that of control group. The relative liver and kidney weights of dalsaengtang treated group were also increased to that of control group. There were no significant changes between two groups in blood chemistry and hematological values. There were no significant changes in number of corpus luteum, implantation, live fetuses and implantation rate, delivery rate, late resorption rate and sex ratio. But Dalsaengtang administered group showed lower early resorption rate than the control group. From the sex ratio, number of females, bigger than number of males in the control group, and more males than females in Dalsaengtang administered group. Neonatal body weight and number of fetus of Dalsaengtang group were increased to that of control group. The fetuses of dams treated with Dalsaengtang didn't showed external malformation. Vertebral and sternal variations were observed in Dalsaengtang group but, compared to the control, those variations were insignificant. The number of ribs, cervical, thoracic, and lumber were normal. The number of sacral and caudal vertebrae were increased. Fetuses showed significant difference in the number of caudal vertebra (P<0.01). From these results, it can be concluded that Dalsaengtang showed no toxicity effects on maternal body weight, early resorption rate, and number of live fetuses. There were no significant changes in organ weight, hematological data, reproductive organs. Although skeletal variations were showed in vertebrate and sternum, Dalsaengtang did not shown significant changes in bone malformation.

• Imaging Science in Dentistry
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• 제30권3호
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• pp.189-198
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• 2000

Purpose: The study was aimed to detect the induction of apoptosis, cell cycle arrest and calcified nodule formation after irradiation on primarily cultured osteoblasts. Materials and Methods: Using rat calvarial osteoblasts, the effects of irradiation on apoptosis, cell cycle arrest, and calcified nodule formation were studied. The single irradiation of 10 and 20 Gy was done with 5.38 Gy/min dose rate using the l37Cs cell irradiator at 4th and 14th day of culture. Apoptosis induction and cell cycle arrest were assayed by the flowcytometry at 1, 2, 3, and 4 days after irradiation. The formation of calcified nodules was observed by alizarin red staining at 1, 3, 10, 14 days after irradiation at 4th day of culture, and at 1, 4, 5 days after irradiation at 14th day of culture. Results: Apoptosis was not induced by 10 or 20 Gy independent of irradiation and culture period. Irradiation did not induced G1 arrest in post-irradiated ostedblasts. After irradiation at 4th-day of culture, G2 arrest was induced but it was not statistically significant after irradiation at 14th-day of culture. In the case of irradiated cells at 4th day of culture, calcified nodules were not formed and at 14th-day of culture after irradiation, calcified nodule formation did not affected. Conclusion: Taken together, these results suggest that irradiation at the dose of 10-20 Gy would not affect apoptosis induction of osteoblasts. Cell cycle and calcified nodule formation were influenced by the level of differentiation of osteblasts.

• 한국해양학회지
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• 제5권1호
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• pp.37-40
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• 1970

삼치, Scomberomorus niphonius (Cuvier et Valenciennes), 는 우리나라 수출전략어종중 가장 중요한 위치를 차지하고 있는 어종의 하나이며 1968년도 삼치총어획고는 7,590 M/T으로서 7억1천4백여만원선에 달하였으며 이중 거의 전량이 수출되고 있다. 이와같이 경제적 위치가 높은 어종인데도 불구하고 삼치자원에 대한 조사연구보고는 전혀 없어 이 자원에 대한 조사연구가 절실히 요망되어 왔었다. 필자는 자원해석을 행함에 있어서 무엇보다 기분적인 지견이 되는 성장과 년령과의 관계를 구명하기 위한 제1차 조사작업으로 삼치의 년령사정법에 관한 문제를 취급하였다. 1969년에 발생한 서남해안 일대의 코레라 사태와 제한된 연구기간등으로 인한 계절적 자료의 부족으로 상기목적에 적합한 표분을 계통적으로 수집하기 못해 완전한 검토는 못하였지만 일부 1969년도 자료를 분석한 결과 춘추골로서 년령사정이 가능하다는 것을 알게 되어 이에 그 개요를 보고한다.

• 한국식품영양과학회지
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• 제39권2호
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• pp.203-209
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• 2010

본 연구를 통하여 여주 추출물은 세포 증식을 제외하고는 조골세포에 긍정적인 영향을 미치지 못하였지만 머위 추출물은 세포의 증식, ALP 활성, bone nodule의 형성이 대조군과 비슷한 결과를 나타내거나 높은 경향을 나타냄으로써 조골세포의 골 형성 과정인 증식, 기질의 성숙, 기질의 석회화의 세 단계에서 유효성을 증명하였다. 또한 OPG mRNA의 2배 이상의 증가는 조골세포의 골 형성에 주요 매개 물질로서 가능성이 있음을 밝혔다. 따라서 머위 추출물은 골수의 미세 환경에서 세포의 조절작용을 하는 물질로 여겨지며, 골다공증을 포함한 각종 골 결손 질환의 예방과 치료약 개발에 긍정적인 가능성을 제시할 것이라 사료된다.

• 생명과학회지
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• 제16권6호
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• pp.925-931
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• 2006

골조직은 골아세포, 파골세포, 골세포 등으로 구성되며, 골개조시 여러 인자가 세포증식, 분화, 활성화 및 골대사 조절에 관여한다. 이때 조골세포의 활성은 골형성에 중요하므로, 본 연구에서는 MC3T3-E1 조골세포주를 이용하여 해조류로 조제한 알칼리의 ENA-A 이온수가 조골세포의 증식과 분화활성에 미치는 영향을 조사하였다. 먼저 ENA-A 이온수가 조골세포의 성장에 미치는 영향을 MTT 검색법으로 조사 한 결과, ENA-A 이온수 2% 처리시 대조군과 비교하여 134% 증가하여 조골세포에 대해 높은 성장률을 보였다. 또한 ALP 효소 활성에 미치는 영향을 9일간 배양하여 그 변화를 측정하였다. 결과, 농도 1, 2, 4, 8% 처리시 112, 150, 188%까지 ALP 활성을 증가시켰다. ENA-A 이온수는 다시 ALP 효소 염색법과 Alizarin Red 염색으로 조골세포의 ALP활성유도, 분화와 석회화 형성능을 재확인하였으며 골기질 유전자의 발현의 변화도 확인하였다. 이에 본 연구결과를 통해 각종 무기질 성분을 함유한 ENA 이온수가 조골세포의 분화시에 hydroxyapatite 형성에 영향을 줌으로써 골다공증 예방에 효과가 있을것으로 생각하여 이를 보고하는 바이다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권1호
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• pp.24-39
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• 2000

Various methods and graft materials have been used to fill in the defect adjacent to the implants and considered as clinically acceptable. But it is not clear whether the regenerated bone increases the implant-bone contact and supports the implant. The purpose of this study is to evaluate regenerated bone surrounding implants using bone morphogenetic protein(BMP) and demineralized freeze-dried bone(DFDB), and the interfaces between implants and regenerated bone. bBMP was extracted and partially purified from the bovine bone matrix using heparine chromatography. Demineralized freeze-dried bone was made from the dog. Inactive insoluble collagenous bone matrix(IBM) of dog was used as carrier of bBMP. Interfaces of titanium coated epoxy resin implants were processed for demineralized section for transmission electron microscopy(TEM) and those of screw type implants were for nondemineralized section for light and fluoromicroscopic examination. Implants were inserted in the inferior border of mandible of adult dogs and artificial bony defects($3{\times}3{\times}4mm$) were made at the mesial and distal side of implants. Defects were filled with BMP(BMP group) and DFDB(DFDB group). For the fluoromicroscopic examination, the fluorescent dyes(oxytetracycline, calcein green, alizarin red) were injected 2, 4, 6, 8, 12 weeks after implantation. The experimental animals were sacrificed at the 6th and the 12th week and their mandible were extirpated and processed for examination with light microscopy, fluoromicroscopy and TEM. The obtained results were as follows : 1. By the light microscopic findings, the defects were filled with woven bone at the 6th week and compact bone at the 12th week, and the osseointegrations were seen in both groups. There was no histological difference between them. 2. On the basis of the histomorphometric analysis, BMP group(6th week: 40.25%, 12th week: 56.04%) had higher bony contact ratio than DFDB group(38.37%, 42.63%). There was significant difference between two groups at the 12th week(p<0.05). 3. The amount of bone formation in BMP group was more prominent than in DFDB group. Significant difference was noted among two groups at the 6th and the 8th week(p<0.05). 4. By the transmission electron microscopic findings, $0.4-2{\mu}m$ soft tissue layer was found in adjacent to the interfaces and over the collagen fibrils of bone at the 6th week. However, about 100nm amorphous layer was noted at the interface or collagen fibrils directly extended to the titanium surface at the 12th week. There was no significant difference between two groups. 5. These results suggest that BMP and DFDB can be used as good graft materials in the regeneration of bone adjacent to implant, and BMP is more valuable as a bone inducer than DFDB.

• Journal of Acupuncture Research
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• 제23권5호
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• pp.69-77
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• 2006

Background : Mesenchymal stem cells (MSCs) are present in most of the tissue matrix, taking part in their regeneration when injury or damage occurs. The aim of this study was to investigate the presence of cells with pluripotential characteristics in human subchondral bone and the capacity of these cells to differentiate to osteoblast. Methods : Human subchondral bone were digested with collagenase. Isolated cells were cultured with a-MEM, 15% FBS, 10-8M dexamethasone and 50 ng/mL ascoric acid. Cells from 0 day(isolated cells), 7 day (first subculture) and 14 days (third subculture) were used to carry out phenotypic characterization experiments flowcytometry analysis with 11 monoclonal antibodies) and osteogenic differentiation experiments. Osteogenic differentiation of cells was assessment by quantification of bone extracellular matrix components by following analysis: alkaline phosphatase(ALP) stains to detect ALP activity, RT-PCR and western blot to detect osteocalcin (OCN), osteopontin (OPN) and type I collagen(Col I), and Alizarin red stains to detect calcium deposition. Results : Flowcytometry analyses showed that in our population more than 98% of cells were positive for MSC markers: SH-2(CD105, 99%), CD29 (95%), CD73 (95%). Cells were negative for hematopoietic markers (CD11b, CD34, and CD45). Furthermore, cells showed positive stain to multipotent markers such as CDl17 (c-kit) (15.1%), and CD166 (74.9%), and cell adhesion molecules such as CD54 (78.1%) and CD106 (63.5%). The osteogenic specific marker analyses showed that the culture of these cells for 7 and 14 days stimulates ALP, OCN, OPN and Col I synthesis by RT-PCR and Western blot analysis. Also, after 14 days in the culture of MSCs induces mineralization by Arizarin red stain. Conclusion : In this work, we demonstrated a new and efficient method for osteoblastic differentiation of human subchondral bone stem cells. As MSCs takes part in reparative processes of adult tissues, these cells could play an important role in osteogenesis.

• Journal of Periodontal and Implant Science
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• 제34권3호
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• pp.475-487
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• 2004

Purpose: This study was aimed to evaluate the effect of the deproteinated bovine bone powder (DBBP) coated with calcium phosphate (Ca-P) on osseous regeneration in the calvarial bone defect of rat. Materials and Methods : The DBBP (Control group, n=6) and the Ca-P coated DBBP (Experimental group, n=6) were grafted in the critical sized calvarial bone defect (8 mm) of rat weighing 250 g. The animals were sacrificed at 1, 4 week. The biopsy specimens were decalcified with 5%formaldehyde and embedded in paraffin. The rats were sacrificed at 8 week received tetracycline (1 week), calcein blue (4 week), and alizarin red (7 week), and the biopsy specimens were taken. The specimens were embedded in methylmethacrylate and ground to 10 ${\mu}m$ thin sections were made. All of the specimens were stained with H & E and Masson's trichrome and examined under light microscope. The specimens at 8 week were examined under fluorescent microscope. Results : In the Control group, the grafted DBBP was surrounded with connective tissue, and osteoblasts were observed partially around the grafted particles at 1 week. At 4 week, some osteoid was observed and, new bone formation was observed at the periphery of grafted materials at 8 week, In the Experimental group, some osteoid was seen at the periphery of the grafted Ca-P coated DBBP at 1 week, and osteoblast and newly formed bone were observed around the grafted materials. At 8 week, newly formed bone was observed at the periphery of the grafted materials. Conclusion: These results suggest that Ca-P coated DBBP group was more and faster than DBBP group in new bone formation and Ca-P could contribute to enhance bone formation in the critical sized calvarial bone defect of rat.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제39권
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• pp.7.1-7.9
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• 2017

Background: This study was to investigate the effect of biomechanical stimulation on osteoblast differentiation of human periosteal-derived stem cell using the newly developed bioreactor. Methods: Human periosteal-derived stem cells were harvested from the mandible during the extraction of an impacted third molar. Using the new bioreactor, 4% cyclic equibiaxial tension force (0.5 Hz) was applied for 2 and 8 h on the stem cells and cultured for 3, 7, and 14 days on the osteogenic medium. Biochemical changes of the osteoblasts after the biomechanical stimulation were investigated. No treatment group was referred to as control group. Results: Alkaline phosphatase (ALP) activity and ALP messenger RNA (mRNA) expression level were higher in the strain group than those in the control group. The osteocalcin and osteonectin mRNA expressions were higher in the strain group compared to those in the control group on days 7 and 14. The vascular endothelial growth factor (VEGF) mRNA expression was higher in the strain group in comparison to that in the control group. Concentration of alizarin red S corresponding to calcium content was higher in the strain group than in the control group. Conclusions: The study suggests that cyclic tension force could influence the osteoblast differentiation of periosteal-derived stem cells under optimal stimulation condition and the force could be applicable for tissue engineering.