• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.6
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• pp.511-519
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• 2006

Autogenous bone grafts have been considered the gold standard for maxillofacial bony defects. However, this procedure could entail a complicated surgical procedure as well as potential donor site morbidity. Possibly the best solution for bone-defect regeneration is a tissue engineering approach, i.e. the use of a combination of a suitable scaffold with osteogenic cells. A major source of osteogenic cells is the bone marrow. Bone marrow-derived mesenchymal stem cells are multipotent and have the ability to differentiate into osteoblastic, chondrocytic, and adipocytic lineage cells. However, the isolation of cells from bone marrow has someproblems when used in clinical setting. Bone marrow aspiration is sometimes potentially more invasive and painful procedure and carries of a risk of morbidity and infection. A minimally invasive, easily accessible alternative would be cells derived from periosteum. The periosteum also contains multipotent cells that have the potential to differentiate into osteoblasts and chondrocytes. In the present study, we evaluated the osteogenic activity and mineralization of cultured human periosteal-derived cells. Periosteal explants were harvested from mandibule during surgical extraction of lower impacted third molar. The periosteal cells were cultured in the osteogenic inductive medium consisting of DMEM supplemented with 10% fetal calf serum, 50g/ml L-ascorbic acid 2-phosphate, 10 nmol dexamethasone and 10 mM -glycerophosphate for 42 days. Periosteal-derived cells showed positive alkaline phosphatase (ALP) staining during 42 days of culture period. The formation of ALP stain showed its maximal manifestation at day 14 of culture period, then decreased in intensity during the culture period. ALP mRNA expression increased up to day 14 with a decrease thereafter. Osteocalcin mRNA expression appeared at day 7 in culture, after that its expression continuously increased in a time-dependent manner up to the entire duration of culture. Von Kossa-positive mineralization nodules were first present at day 14 in culture followed by an increased number of positive nodules during the entire duration of the culture period. In conclusion, our study showed that cultured human periosteal-derived cells differentiated into active osteoblastic cells that were involved in synthesis of bone matrix and the subsequent mineralization of the matrix. As the periosteal-derived cells, easily harvested from intraoral procedure such as surgical extraction of impacted third molar, has the excellent potential of osteogenic capacity, tissue-engineered bone using periosteal-derived cells could be the best choice in reconstruction of maxillofacial bony defects.

• Journal of Periodontal and Implant Science
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• v.41 no.5
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• pp.227-233
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• 2011

Purpose: The aim of this study was to compare osteoblast behavior on zirconia and titanium under conditions cultured with bone morphogenetic protein-2. Methods: MC3T3-E1 cells were cultured on sandblasted zirconia and sandblasted/etched titanium discs. At 24 hours after seeding MC3T3-E1, the demineralized bone matrix (DBM) gel alone and the DBM gel with bone morphogenetic protein-2 (BMP-2) were added to the culture medium. The surface topography was examined by confocal laser scanning microscopy. Cellular proliferation was measured at 1, 4, and 7 days after gel loading. Alkaline phosphatase activity was measured at 7 days after gel loading. The mRNA expression of ALPase, bone sialoprotein, type I collagen, runt-related transcription factor 2 (Runx-2), osteocalcin, and osterix were evaluated by real-time polymerase chain reaction at 4 days and 7 days. Results: At 1, 4, and 7 days after loading the DBM gel alone and the DBM gel with BMP-2, cellular proliferation on the zirconia and titanium discs was similar and that of the groups cultured with the DBM gel alone and the DBM gel with BMP-2 was not significantly different, except for titanium with BMP-2 gel. ALPase activity was higher in the cells cultured with BMP-2 than in the other groups, but there was no difference between the zirconia and titanium. In ALPase, bone sialoprotein, osteocalcin, Runx-2 and osterix gene expression, that of cells on zirconia or titanium with BMP-2 gel was much more highly increased than titanium without gel at day 7. The gene expression level of cells cultured on zirconia with BMP-2 was higher than that on titanium with BMP-2 at day 7. Conclusions: The data in this study demonstrate that the osteoblastic cell attachment and proliferation of zirconia were comparable to those of titanium. With the stimulation of BMP-2, zirconia has a more pronounced effect on the proliferation and differentiation of the osteoblastic cells compared with titanium.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.5
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• pp.386-395
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• 2011

Introduction: Osteoporosis is a major health problem in the elderly that involves changes in the properties of bone as well as impaired bone healing around a titanium implant in both humans and animals. This study examined effect of low intensity pulsed ultrasound (LIPUS) on the bone healing process around a titanium implant in osteoporosis-induced rats. Materials and Methods: Sixteen rats were divided into two groups. A control group with osteoporosis induced by removing both ovaries and an experimental group of rats that were applied with LIPUS after osteoporosis had been induced. A screw type titanium implant (diameter, 2.0 mm: length, 3.5 mm, Cowell-Medi, KOREA) was placed into the tibias of 16 rats. The control and experimental group contained 8 rats each. The rats were sacrificed at 1, 2, 4, and 8 weeks after implantation to examine the histopathology and immunochemistry. Results: The histopathology examination revealed earlier new bone formation in the experimental group than the control group. In particular, at 1 week after implantation, more new bone matrix and collagen were observed around the implant of the experimental group compared to the control group. Immunochemistry analysis showed that the level of OPG expression of the experimental group was higher in the early stages than in the control group. After 8 weeks, the levels of OPG expression were similar in both groups. The expression level of receptor activator of nuclear factor kB ligand (RANKL) was stronger in the experimental group than the control group. After 4 weeks, the level of RANKL expression was similar in both groups. Conclusion: These results suggest that the application of LIPUS to implantation can promote bone healing around titanium in osteoporosis animals.

• Journal of Periodontal and Implant Science
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• v.31 no.3
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• pp.555-564
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• 2001

The purpose of this study is to evaluate the bioresorbability of Calcium Polyphosphate added with $Na_2O$ and chitosan. Though calcium phosphate ceramics meet some of the needs for bone replacement, they have some limitation of unresorbability and fibrous encapsulation without direct bone apposition during bone remodelling. To solve these problem, we developed a new ceramic, calcium polyphosphate(CPP), and report the biologic response to CPP in extraction sites of beagle dog. Porous CPP granules were prepared by condensation of anhydrous $Ca(H_2PO_4)_2$ to form non-crystalline $Ca(PO_3)_2$. CPP granules added with $Na_2O$ and chitosan were implanted in extraction sockets and histologic observation were performed at 12 weeks later. Histologic observation at 12 weeks revealed that CPP matrix were mingled with and directly apposed to new bone without any intervention of fibrous connective tissue. CPP granules added with chitosan were well adatped without any adverse tissue reaction and resorbed slowly and spontaneously. CPP granules added with $Na_2O$ and chitosan show multinucleated giant cells and osteoblast-like cells around grafted material and newly formed bone. This result revealed that CPP, regardless of its additive component, had a high affinity for bone and had been resorbed slowly. From this results, it was suggested that CPP is promising ceramic as a bone substitute and addition of $Na_2O$ and chitosan help biodegradation. In further study , it will be determined which concentration of $Na_2O$ help biodegradation and the other additive components increase the degradation rate.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.5
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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.

• Journal of Periodontal and Implant Science
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• v.33 no.2
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• pp.225-246
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• 2003

Recent study on the enamel matrix derivatives explained on the effects of new bone and new attachment formation in infrabony pocket of periodontal defects. The purpose of this study was to investigate on the biological effects of enamel matrix derivatives to attachment, proliferation and activation of periodontal ligament and osteoblast cells, After treatment of osteoblast and PDL cells with various Emdogain concentration level(0.03${\mu}g$/ml, 3${\mu}g$/ml, 300${\mu}g$/ml), activation of osteogenetic factor, calcified nodule formation and measuring alkaline phosphatase activity(ALP) were performed. 1. Both osteoblast and PDL cell showed increasing initial cell attachment with 300${\mu}g$/ml Emdogain concentration. 2. At the level of 300${\mu}g$/ml, accelerated proliferation of oseoblast and PDL cell was appeared. 3. As Emdogain's concentration increased, increased ALP activation of osteoblast was shown. In case of PDL cell, Emdogain increased ALP activation prominently at the level of 300${\mu}g$/ml. 4. No statistically significant activating change were founded at all of the concentrations of Emdogain on the activating of transcript factor Runx2 for differentiating osteoblast. 5. At the level of 300${\mu}g$/ml, calcified nodule formation was increased prominently to compare with other concentration. These results indicated that Emdogain should activate initial attachment, proliferation and activation, but not on Runx2 activation and can be used for useful tool of the treatment of periodontal tissue regeneration.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3331-3335
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• 2013

Background: The incidence of prostate cancer, one of the most common cancers in elderly men, is increasing annually in Thailand. Matrix metalloproteinase 11 (MMP-11) is a member of the extracellular matrix metalloproteases which has been associated with human tumor progression and clinical outcome. Aim: To quantify MMP-11 expression in prostatic adenocarcinoma tissues and to determine whether its overexpression correlates with survival outcome, and to assess its potential as a new prognostic marker. Materials and Methods: Expression of MMP-11 was analyzed using immunohistochemistry in 103 Thai patients with prostatic adenocarcinoma. Overall survival was analyzed using Kaplan-Meier methods and Cox regression models. Results: Immunoreactivity of MMP-11 was seen in the stroma of prostatic adenocarcinoma tissue samples, high expression being significantly correlated with poor differentiation in Gleason grading, pathologic tumor stage 4 (pT4), and positive-bone metastasis (p<0.05), but not age and prostatic-specific antigen (PSA) level. Patients with high levels of MMP-11 expression demonstrated significantly shorter survival (p<0.001) when compared to those with low levels. Multivariate analysis showed that MMP-11 expression and pT stage were related with survival in prostatic adenocarcinoma [hazard ratio (HR)=0.448, 95% confidence interval (95%CI)=0.212-0.946, HR=0.333, 95%CI=0.15-0.74, respectively]. Conclusions: Expression of MMP-11 is significantly associated with survival in prostatic adenocarcinoma. High levels may potentially be used for prediction of a poor prognosis.

• Journal of the Korean Arthroscopy Society
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• v.11 no.1
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• pp.1-6
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• 2007

Purpose: The purpose of this preliminary report is to investigate the short term outcome of performing gel type fibrin matrix autologous chondrocyte implantation to patients who have damaged knee joint cartilage using secondary arthroscopy. Material and Methods: Six patients who have damaged knee joint cartilage were involved. The average size of defect was $5.13\;cm^2$. While performing primary arthroscopy, whole layer of cartilage bone was obtained either from the margin of damaged cartilage or the bilateral margin of a trochlea. The cartilaginous cells were obtained for culture for four to six weeks. While performing secondary minimal invasive arthrotomy, gel type fibrin matrix autologous chondrocyte was implanted on the chondral defect site. Results: 4 among 6 patients to be more than good in Modified Cincinnati Knee Scoring system. Lysholm function score was 59.5 preoperatively, and it improved to 76.25. ICRS grading by performing secondary arthroscopy revealed 4 out of 6 patients to be nearly normal. Conclusion: Gel type fibrin matrix autologous chondrocyte implantation is a treatment for cartilage defect, which takes less time to operate than the conventional implantation. In addition, this method minimizes the size of incision and allows arthroscopic surgery. However, long term follow up and more case study is thought to be necessary.

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.1
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• pp.23-27
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• 2018

Purpose The introduction of bone scan has been reported as a useful tool in the diagnosis, treatment, and treatment response of skeletal disease. The purpose of this study is to improve the anatomical information and tolerance of the bone by combining bone scan and pelvic X-ray without additional radiation exposure. Materials and Methods From November 2015 to August 2016, 236 patients(64 men and 172 women, average age $50.96{\pm}15.39years$) take Bone scan and Pelvis AP(Anteroposterior) X-ray scan at the National Cancer Center. The scan equipment was a gamma camera, Symbia Ecam (SIEMENS, Germany), and a digital x-ray, DRS-800 (Listem, Korea). Osirix version 3.8.1 (Osirix, USA) and Stata/SE version 14.0 (StataCorp, USA) were used for image combination and analysis. The patient was intravenously injected with $^{99m}Tc-DPD$ (740 MBq), and the scan was performed 2 to 4 hours later. Gamma camera image acquisition were Matrix size $256{\times}1024$, Zoom 1.00, and scan speed 17 cm/min. The digital X-ray was made with a collimator size of $14^{{\prime}{\prime}}{\times}17^{{\prime}{\prime}}$, 77 kVp (60 to 97 kVp) and an average of 30 mAs (20 to 48). ASIS and pubic symphysis Select virtual points then Combine three virtual points and pelvic contour lines. The acquired images were evaluated by three radiologists who worked for more than 5 years in the nuclear medicine department. Results Of the total 236 patients, 216 (91.53%) were matched. The median and range (min~max) of the age were 67 (46~81) years old in the unmatched group and 52 (22~87) years old in the matched group, The Wilcoxon rank-sum test was performed to determine whether age was different between the two groups. As a result, the age difference between the two groups was statistically significant at p < 0.0001. Of the 64 men, 60 (93.75%) were match and of the 172 women, 156 (93.75%) were match. There was no statistically significant difference according to gender(p = 0.4542). Of the 54 patients without pelvic lesions, 54 (100.00%) were match, and 162 (89.01%) of 182 patients with pelvic lesions were match. There was a statistically significant difference according to the presence of pelvic lesions. Conclusion There are many variables in the combination of bone scan and pelvic X-ray imaging, and the patient's age and pelvic lesion may have some effect on the image combination. This study is expected to be useful for the diagnosis of pelvic osteosarcoma of children without radiation exposure. It is expected that this combination of images will help to develop the nuclear medicine image.

• Journal of Periodontal and Implant Science
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• v.29 no.3
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• pp.507-519
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• 1999

The ultimate objective of periodontal treatment is to stop disease progression and to regenerate destroyed periodontal tissues and thereby regain normal function. Growth factors are naturally found polypetides which stimulate many cellular activities pertaining to wound healing by acting as signal molecule in controlling cell movement, proliferation, and matrix production. Platelet derived growth factor (PDGF) is 28,000-35,000 Da molecular weight dimeric protein with 2 long positively charged polypeptide chains connected by sulfide bonds. The purpose of this study is to evaluate histologically the initial guided tissue regeneration in a periodontal defect f a beagle dog treated with a biodegradable membrane formed with polylactic acid (poly-L-lactic acid) and polyglycolic acid loaded with 200ng/$cm^2$ platelet derived growth factor. 2 beagle dogs were used in he experiment. $5mm{\times}6mm$ alveolar bone defect was formed in upper and lower canines and third premolars and a reference notch was placed. PDGF-BB non-containing membrane was used as control. Each defect was randomly assigned to the test roup or the control group. The dogs were sacrificed 3 weeks after membrane placement. Toluidine blue and multiple staining was done for histological analysis. In the 3 week specimen in the control group, no new one formation could be seen. Small amount f bone resorption below the notch could be seen. In the notch, loose connective tissue with infiltration of inflammatory cells could be seen. Also thin discontinuous new cementum could be seen and the membrane still retained its structure. Where PDGF-BB containing membrane was used, new bone formation could be seen in the notch at weeks and also continuous thin cementum could be seen. PDL cells were observed between new bone and new cementum and some were attached to bone and cementum. These results suggest that new bone and cementum formation seen when PDGF-BB loaded membrane was used was due to inhibition of downgrowth of epithelial cells and also due to continuous release of the growth factor. Further study on the resorption characteristics of the membrane nd the release characteristics of the PDGF-BB is necessary. Also, development of a membrane easier to use clinically is necessary.