• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.30 no.5
• /
• pp.428-433
• /
• 2004

Sinus floor augmentation has been proven an effective treatment procedure to increase bone volume in the posterior edentulous maxilla. Autogenous bone considered to be the best material for reconstructive bone surgery and has been successfully used as a graft material to augment posterior maxilla. However, the collection of autogenous bone required extra risks for morbidity and complaints. So, various bone graft materials included ${\beta}$-tricalcium phosphate(${\beta}$-TCP) has been introduced for replacing the autogenous bone. The objective of this clinical study was to determine the predictability of endosseous implant placed in a maxillary sinus with ${\beta}$-TCP grafting. We performed sinus elevation with ${\beta}$-TCP to install the implant in the 10 maxillary cases. The prosthetic procedure was performed 6-9 months after. The implant-prosthetics was checked about 1 year. We checked the implant and measured the maximum bite force to evaluate the function of the implant. There was not observed the specific problem and complication in dental implant and maxillary sinus in the grafted materials. The maximum bite force was 558N in case of natural tooth, 365N in implant without grafting, 318N in implant with ${\beta}$-TCP grafting. There was no significant difference between with and without sinus grafting on maximum bite force(p>0.05). As though the long term check-up is needed, the grafting of ${\beta}$-TCP as a osteoconductive materials can expand the volume and induce dense new bone formation in maxillary sinus. So, this short-term results support that ${\beta}$-TCP can be a suitable material for sinus augmentation.

• Journal of Periodontal and Implant Science
• /
• v.36 no.4
• /
• pp.797-808
• /
• 2006

Objective : The purpose of this study was to evaluate the physicochemical properties and cytocompatibility of microporous, spherical biphasic calcium phosphate(BCP) ceramics with a 60/40 $hydroxyapatite/{\beta}$ -tricalcium phosphate weight ratio for application as a bone graft substitute. Materials and Methods : Microporous, spherical BCP granules(MGSB) were prepared and their basic characteristics were compared with commercially available BCP(MBCP; Biomatlante, France) and deproteinized bovine bone mineral(Bio-Oss; GBistlich-Pharma, Switzerland, BBP; Oscotec. Korea), Their physicochemical properties were evaluated by scanning electron microscopy, X-ray diffractometry, Fourier-transform infrared spectroscopy, inductively coupled plasma atomic emission spectrometer, and Brunauer-Emmett-Teller method. Cell viability and proliferation of MC3T3-El cells on different graft materials were evaluated. Results : MGSB granules showed a chemical composition and crystallinity similar with those in MBCP, they showed surface structure characteristic of three dimensionally, well-interconnected micropores. The results of MTT assay showed increases in cell viablity with increasing incubation times. At 4d of incubation, MGSB, MBCP and BBP showed similar values in optical density, but Bio-Oss exhibited significantly lower optical density compared to other bone substitutes(p <0,05). MGSB showed significantly greater cell number compared to other bone substitutes at 3, 5, and 7d of incubation(p <0,05), which were similar with those in polystyrene culture plates. Conclusion: These results indicated the suitable physicochemical properties of MGSB granules for application as an effective bone graft substitute. which provided compatible environment for osteoblast cell growth. However, further detailed studies are needed to confirm its biological effects on bone formation in vivo.

• Journal of Periodontal and Implant Science
• /
• v.41 no.2
• /
• pp.67-72
• /
• 2011

Purpose: The aim of this study is to determine whether certain biomaterials have the potential to support cell attachment. After seeding bone marrow stromal cells onto the biomaterials, we investigated their responses to each material in vitro. Methods: Rat bone marrow derived stromal cells were used. The biomaterials were deproteinized bovine bone mineral (DBBM), DBBM coated with fibronectin (FN), synthetic hydroxyapatite (HA), HA coated with FN, HA coated with $\beta$-tricalcium phosphate (TCP), and pure $\beta$-TCP. With confocal laser scanning microscopy, actin filaments and vinculin were observed after 6, 12, and 24 hours of cell seeding. The morphological features of cells on each biomaterial were observed using scanning electron microscopy at day 1 and 7. Results: The cells on HA/FN and HA spread widely and showed better defined actin cytoskeletons than those on the other biomaterials. At the initial phase, FN seemed to have a favorable effect on cell adhesion. In DBBM, very few cells adhered to the surface. Conclusions: Within the limitations of this study, we can conclude that in contrast with DBBM not supporting cell attachment, HA provided a more favorable environment with respect to cell attachment.

• International Journal of Oral Biology
• /
• v.30 no.3
• /
• pp.99-103
• /
• 2005

Bone morphogenetic proteins (BMPs), members of a large group of TGF-beta family, are important molecular regulators of morphogenesis of numerous tissues and organs, including bones and teeth. Most BMPs are capable of inducing bone formation in vivo and therefore are of considerable clinical interest for regenerating mineralized tissues. Recently, we have developed a method to culture cells from human cementum (human cementum-derived cells, HCDCs). HCDCs, when attached to synthetic hydroxyapatite/tricalcium phosphate (HA/TCP) ceramic and transplanted into immunodeficient mice, formed histologically identifiable cementum-like tissue. Since it is unclear to what extent BMPs are involved in cementogenesis, the aim of this study was to establish which BMPs are expressed by cementogenic HCDCs and whether the expression of BMPs is related to the degree of cellular differentiation in vitro. HCDCs were maintained in growth medium (DMEM/F12 supplemented with 10% FBS) until confluent (proliferation stage). Upon reaching confluence, cells were incubated in the differentiation medium (DMEM/F12 medium containing 10% FBS and 50 mg/ml ascorbic acid) for 14 days (differentiation stage). Next, HCDCs were incubated in mineralization medium (DMEM/F12, 50 mg/ml ascorbic acid, 2.5 mg/ml of ITS (insulin-transferrinselenium), 5 mM beta-glycerophosphate and $10^{-8}M$ dexamethasone) for another 14 days (mineralization stage). At the end of each differentiation stage, total RNA was isolated and evaluated for BMPs (2 through 8) expression by employing real time RT-PCR. HCDCs expressed most of BMPs examined except BMP-7 and BMP-8. Furthermore, on average, the highest levels of BMPs were expressed at the earlier differentiation stage, prior to the initiation of mineralization in vitro. These results indicate that several BMPs are expressed during cementoblastic differentiation and suggest that BMPs may be involved in the homeostasis of human cementum.

• Journal of Periodontal and Implant Science
• /
• v.50 no.1
• /
• pp.14-27
• /
• 2020

Purpose: To overcome several drawbacks of chemically-crosslinked collagen membranes, modification processes such as ultraviolet (UV) crosslinking and the addition of biphasic calcium phosphate (BCP) to collagen membranes have been introduced. This study evaluated the efficacy and biocompatibility of BCP-supplemented UV-crosslinked collagen membrane for guided bone regeneration (GBR) in a rabbit calvarial model. Methods: Four circular bone defects (diameter, 8 mm) were created in the calvarium of 10 rabbits. Each defect was randomly allocated to one of the following groups: 1) the sham control group (spontaneous healing); 2) the M group (defect coverage with a BCP-supplemented UV-crosslinked collagen membrane and no graft material); 3) the BG (defects filled with BCP particles without membrane coverage); and 4) the BG+M group (defects filled with BCP particles and covered with a BCP-supplemented UV-crosslinked collagen membrane in a conventional GBR procedure). At 2 and 8 weeks, rabbits were sacrificed, and experimental defects were investigated histologically and by micro-computed tomography (micro-CT). Results: In both micro-CT and histometric analyses, the BG and BG+M groups at both 2 and 8 weeks showed significantly higher new bone formation than the control group. On micro-CT, the new bone volume of the BG+M group (48.39±5.47 ㎣) was larger than that of the BG group (38.71±2.24 ㎣, P=0.032) at 8 weeks. Histologically, greater new bone area was observed in the BG+M group than in the BG or M groups. BCP-supplemented UV-crosslinked collagen membrane did not cause an abnormal cellular reaction and was stable until 8 weeks. Conclusions: Enhanced new bone formation in GBR can be achieved by simultaneously using bone graft material and a BCP-supplemented UV-crosslinked collagen membrane, which showed high biocompatibility and resistance to degradation, making it a biocompatible alternative to chemically-crosslinked collagen membranes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.36 no.6
• /
• pp.466-472
• /
• 2010

Introduction: This study examined the effect of recombinant human bone morphogenetic protein (rhBMP)-2 and $\beta$-tricalcium phosphate ($\beta$-TCP) on new bone formation in a rabbit calvarium using a rapid prototype titanium cap (RP Ti cap). Materials and Methods: Eight New Zealand white rabbits were used in this study. Hemispherical RP Ti caps (10 mm in diameter) were implanted subperiosteally on the rabbit calvaria. $\beta$-TCP was filled in the RP Ti cap in the control group, and rhBMP-2 soaked $\beta$-TCP was used in experimental group. The rabbits were sacrificed 2 and 4 weeks after the operation. The volume and pattern of newly formed bone was analyzed by micro computed tomography (CT). Results: Macroscopically, there were no abnormal findings in any of the animals. The micro CT images revealed new bone from the calvaria that expanded gradually toward the top of the titanium cap, particularly along the inner surface of the titanium cap in the experimental group at 4 weeks after grafting. There was no significant difference in new bone volume ratio between the control and experimental groups at 2 weeks after grafting. There was a statistically significant difference in the new bone volume ratio between the experimental ($14.1{\pm}1.8\;%$) and control ($7.2{\pm}1.5\;%$) groups at 4 weeks after grafting (P<0.01). Conclusion: The RP Ti cap can effectively guide new bone formation and rhBMP-2 can induce the new bone formation.

• Journal of Life Science
• /
• v.20 no.8
• /
• pp.1207-1213
• /
• 2010

The purpose of this study was to evaluate the effect of porcine cancellous bone as a scaffold in a rat calvarial defect model. Critical-sized defects were created in 30 male Sprague-Dawley rats. The animals were divided into critical defect (CD, n=10), $\beta$-tricalcium phosphate (TCP) graft (BT, n=10) and porcine cancellous bone graft (PCB, n=10) groups. Each defect was filled with $\beta$-TCP mixed with fibrin glue or porcine cancellous bone powder mixed with fibrin glue. In the CD group, the defect was left empty. All rats were sacrificed at 8 weeks after bone graft surgery, and bone formation was evaluated by gross observation, plain radiography, micro-computed tomography scanning and histological evaluation. Repair of bone defect was the least in the CD group, and significant new bone formation was observed in the PCB group. Grafting of porcine cancellous bone was more efficient for regenerating new bone than grafting $\beta$-TCP.

• Journal of Life Science
• /
• v.28 no.10
• /
• pp.1220-1232
• /
• 2018

The purpose of this animal study was to evaluate, by histological analysis, bone regeneration in rabbit maxillary sinuses with an anorganic bovine graft (Bio-Oss) and a ${\beta}-tricalcium$ phosphate (${\beta}-TCP$) grafting. Bilateral sinus augmentation procedures were performed in 12 adult male rabbits. Rectangular replaceable bony windows were made with a piezoelectric thin saw insert. In the Bio-Oss group, Bio-Oss was grafted and in the ${\beta}-TCP$ group, ${\beta}-TCP$ was grafted and covered by replaceable bony windows. The animals were sacrificed at 2, 4, and 8 weeks after the surgical procedure. The augmented sinuses were evaluated by histomorphometric analysis using hematoxylin-eosin, Masson trichrome, and tartrate-resistant acid phosphatase stains and also by immunohistochemical analysis of proliferating cell nuclear antigen (PCNA), type I collagen, and osteocalcin content. Histologically, new bone formation was found on the surface of Bio-Oss and ${\beta}-TCP$ particles from 2 weeks and continued to 8 weeks. Significant higher new bone formation was revealed in the ${\beta}-TCP$ group than in the Bio-Oss group at 8 weeks. The amount of graft materials was significantly decreased in the ${\beta}-TCP$ group and the number of osteoclasts was significantly increased in the ${\beta}-TCP$ group from 4 to 8 weeks. Immunoreactivity to PCNA was reduced at 8 weeks. The expression of type I collagen was significantly increased in the ${\beta}-TCP$ group at 2 weeks, but was significantly increased in the Bio-Oss group at 8 weeks. Immunoreactivity to osteocalcin was increased from 2 to 8 weeks. These histological results can help in the selection of graft materials for implants. Both Bio-Oss and ${\beta}-TCP$ are proven graft materials, however, these results indicate that ${\beta}-TCP$ showed better bone regeneration results in rabbit maxillary sinus augmentation.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.36 no.1
• /
• pp.25-29
• /
• 2014

The purpose of this study is to report on five cases treated with bone graft using recombinant human bone morphogenetic protein-2 (rhBMP-2) on jaw defects after cyst enucleation. We performed bone graft with BMP (rhBMP-2+${\beta}$-tricalcium phosphate/hydroxyapatite) wrapped with a collagen sponge on jaw defects after cyst enucleation. Postoperative panoramic radiographs were taken periodically. After 1 to 12 months, bone remodeling was observed in the jaw defect area. In our cases, there were few signs or symptoms of recurrence of the cyst during the follow-up period.

• Journal of Periodontal and Implant Science
• /
• v.52 no.3
• /
• pp.242-257
• /
• 2022

Purpose: This study investigated periodontal ligament (PDL) restoration in osseointegrated implants using stem cells. Methods: Commercial pure titanium and zirconium oxide (zirconia) were coated with beta-tricalcium phosphate (β-TCP) using a long-pulse Nd:YAG laser (1,064 nm). Isolated bone marrow mesenchymal cells (BMMSCs) from rabbit tibia and femur, isolated PDL stem cells (PDLSCs) from the lower right incisor, and co-cultured BMMSCs and PDLSCs were tested for periostin markers using an immunofluorescent assay. Implants with 3D-engineered tissue were implanted into the lower right central incisors after extraction from rabbits. Forty implants (Ti or zirconia) were subdivided according to the duration of implantation (healing period: 45 or 90 days). Each subgroup (20 implants) was subdivided into 4 groups (without cells, PDLSC sheets, BMMSC sheets, and co-culture cell sheets). All groups underwent histological testing involving haematoxylin and eosin staining and immunohistochemistry, stereoscopic analysis to measure the PDL width, and field emission scanning electron microscopy (FESEM). The natural lower central incisors were used as controls. Results: The BMMSCs co-cultured with PDLSCs generated a well-formed PDL tissue that exhibited positive periostin expression. Histological analysis showed that the implantation of coated (Ti and zirconia) dental implants without a cell sheet resulted in a well-osseointegrated implant at both healing intervals, which was confirmed with FESEM analysis and negative periostin expression. The mesenchymal tissue structured from PDLSCs only or co-cultured (BMMSCs and PDLSCs) could form a natural periodontal tissue with no significant difference between Ti and zirconia implants, consequently forming a biohybrid dental implant. Green fluorescence for periostin was clearly detected around the biohybrid implants after 45 and 90 days. FESEM showed the invasion of PDL-like fibres perpendicular to the cementum of the bio-hybrid implants. Conclusions: β-TCP-coated (Ti and zirconia) implants generated periodontal tissue and formed biohybrid implants when mesenchymal-tissue-layered cell sheets were isolated from PDLSCs alone or co-cultured BMMSCs and PDLSCs.