• Journal of Periodontal and Implant Science
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• v.40 no.5
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• pp.211-219
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• 2010

Purpose: Fibronectin (FN) has been shown to stimulate bone regeneration in animal models. The aim of this study was to evaluate the capacity of bovine bone mineral coated with synthetic oligopeptides to enhance bone regeneration in rabbit calvarial defects. Methods: Oligopeptides including fibrin-binding sequences of FN repeats were synthesized on the basis of primary and tertiary human plasma FN structures. Peptide coated and uncoated bone minerals were implanted into 10 mm calvarial defects in New Zealand white rabbits, and the animals were sacrificed at 4 or 8 weeks after surgery. After specimens were prepared, histologic examination and histomorphometric analysis were performed. Results: At 4 weeks after surgery, the uncoated groups showed a limited amount of osteoid formation at the periphery of the defect and the oligopeptide coated groups showed more osteoid formation and new bone formation in the center of the defect as well as at the periphery. At 8 weeks, both sites showed increased new bone formation. However, the difference between the two sites had reduced. Conclusions: Fibrin-binding synthetic oligopeptide derived from FN on deproteinized bovine bone enhanced new bone formation in rabbit calvarial defects at the early healing stage. This result suggests that these oligopeptides can be beneficial in reconstructing oral and maxillofacial deformities or in regenerating osseous bone defects.

• The Journal of Advanced Prosthodontics
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• v.5 no.2
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• pp.167-171
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• 2013

PURPOSE. The purpose of this case series was to evaluate the effect of guided bone regeneration using demineralized allogenic bone matrix with calcium sulfate. MATERIALS AND METHODS. Guided bone regeneration using Demineralized Allogenic Bone Matrix with Calcium Sulfate ($AlloMatrix^{TM}$, Wright. USA) was performed at the time of implant placement from February 2010 to April 2010. At the time of the second surgery, clinical evaluation of bone healing and histologic evaluation were performed. The study included 10 patients, and 23 implants were placed. The extent of bony defects around implants was determined by measuring the horizontal and vertical bone defects using a periodontal probe from the mesial, distal, buccal, and lingual sides and calculating the mean and standard deviation of these measurements. Wedge-shaped tissue samples were obtained from 3 patients and histologic examination was performed. RESULTS. In clinical evaluation, it was observed that horizontal bone defects were completely healed with new bones, and in the vertical bone defect area, 15.1% of the original defect area remained. In 3 patients, histological tests were performed, and 16.7-41.7% new bone formation was confirmed. Bone graft materials slowly underwent resorption over time. CONCLUSION. $AlloMatrix^{TM}$ is an allograft material that can be readily manipulated. It does not require the use of barrier membranes, and good bone regeneration can be achieved with time.

• Journal of Periodontal and Implant Science
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• v.37 no.4
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• pp.671-679
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• 2007

Background: $TiUnite^{TM}$ is a highly crystalline and phosphate enriched titanium oxide surface which has a unique porous surface structure. This improved implant surface enhances bone response and reduces healing period. It also assures early stability of implant. These help to increase the success of implant. The aim of this study is to evaluate the survival rate of $TiUnite^{TM}$ surfaced single implant. Materials and methods: A retrospective analysis of 89 $TiUnite^{TM}$ surfaced implants replacing a single tooth was assessed according to their dental record. The age of the patients ranged from 17 to 82 years (mean age: $45.8{\pm}14.6)$. Data were recorded regarding the survival rate of these implants. Results: Fifty-two implants (57%) were placed in the maxilla, and 37 (43%) in the mandible. Over 75% were placed in the posterior area. Of the placed implants, 67% were the wide type. while 25% were the regular type and only 8% were of the narrow type. The single implants produced an overall clinical survival rate of 96.6% over the observation period (mean 17.9 months). Among 89 implants, only 2 implants were removed and one implant was submerged. Conclusion: According to these data, $TiUnite^{TM}$ surfaced implant in a single tooth restoration showed favorable survival rate although this study was done in a short term period.

• Journal of Periodontal and Implant Science
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• v.37 no.4
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• pp.681-690
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• 2007

Mini implants had been used provisionally for the healing period of implants in the beginning. But it becomes used for the on-going purpose, because it is simple to use, economic and especially suitable for the overdenture. But there is few studies about the stability of mini implants, that is most important factor for the on-going purpose, and particularly the implant parameters affecting the initial stability. The purpose of this study was to evaluate the stress and the strain distribution pattern of immediate-loaded screw type orthodontic mini-implant and the parameters affecting the initial stability of immediate-loaded mini-implant. Two dimensional finite element models were made and contact non-linear finite element analysis was performed. The magnitude and distribution of Von Mises stresses were evaluated. The obtained results were as follows: 1. The stress was concentrated on the thread tip of an implant in the cortical bone. 2. The direction of load is the most important factor for the stress distribution in cortical bone. 3. The diameter of an implant is the most important factor for the stress distribution in the trabecular bone. In conclusion, if the horizontal load vector is successfully controlled, mini-implants, which diameter is under 3mm, can be used for the on-going purpose.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.2
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• pp.120-126
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• 2013

Preserving the pulp is important in the treatment of carious pulp exposure in young permanent teeth. Pulpotomy is a vital pulp therapy in which a portion of the coronal pulp tissue is surgically removed, and the remaining radicular tissue is covered with suitable material that protects the pulp from further injury and permits and promotes healing. It is important to develop biocompatible treatment directed at maintaining pulp vitality and increasing tooth longevity. Platelet-rich fibrin (PRF) has been referred to as a second-generation platelet concentrate. Two clinical cases in which PRF was applied as a medicament after pulpotomy of an immature permanent tooth are presented. After isolation, caries removal and pulpotomy with PRF was performed. A layer of mineral trioxide aggregate (MTA) was placed over the PRF, and the final restoration was performed. Postoperatively, the patient had no pain or discomfort, and follow-up radiographs revealed normal periodontal ligament space and trabecular bone pattern.

• Molecules and Cells
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• v.41 no.5
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• pp.476-485
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• 2018

Although tectorigenin (TG), a major compound in the rhizome of Belamcanda chinensis, is conventionally used for the treatment of inflammatory diseases, its effects on osteogenesis and osteoclastogenesis have not been reported. The objective of this study was to investigate the effects and possible underlying mechanism of TG on in vitro osteoblastic differentiation and in vivo bone formation, as well as in vitro osteoclast differentiation and in vivo bone resorption. TG promoted the osteogenic differentiation of primary osteoblasts and periodontal ligament cells. Moreover, TG upregulated the expression of the BMP2, BMP4, and Smad-4 genes, and enhanced the expression of Runx2 and Osterix. In vivo studies involving mouse calvarial bone defects with ${\mu}CT$ and histologic analysis revealed that TG significantly increased new bone formation. Furthermore, TG treatment inhibited osteoclast differentiation and the mRNA levels of osteoclast markers. In vivo studies of mice demonstrated that TG caused the marked attenuation of bone resorption. These results collectively demonstrated that TG stimulated osteogenic differentiation in vitro, increased in vivo bone regeneration, inhibited osteoclast differentiation in vitro, and suppressed inflammatory bone loss in vivo. These novel findings suggest that TG may be useful for bone regeneration and treatment of bone diseases.

• Journal of Periodontal and Implant Science
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• v.50 no.6
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• pp.418-434
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• 2020

Purpose: The purpose of the present study was to evaluate the effect of silica-calcium phosphate composite (SCPC) granules on bone regeneration in extraction sockets. Methods: Ten patients were selected for a split-model study. In each patient, bone healing in SCPC-grafted and control ungrafted sockets was analyzed through clinical, radiographic, histomorphometric, and immunohistochemical assessments 6 months postoperatively. Results: A radiographic assessment using cone-beam computed tomography showed minimal ridge dimension changes in SCPC-grafted sockets, with 0.39 mm and 1.79 mm decreases in height and width, respectively. Core bone biopsy samples were obtained 6 months post-extraction during implant placement and analyzed. The average percent areas occupied by mature bone, woven bone, and remnant particles in the SCPC-grafted sockets were 41.3%±12%, 20.1%±9.5%, and 5.3%±4.4%, respectively. The percent areas of mature bone and woven bone formed in the control ungrafted sockets at the same time point were 31%±14% and 24.1%±9.4%, respectively. Histochemical and immunohistochemical analyses showed dense mineralized bundles of type I collagen with high osteopontin expression intensity in the grafted sockets. The newly formed bone was well vascularized, with numerous active osteoblasts, Haversian systems, and osteocytes indicating maturation. In contrast, the new bone in the control ungrafted sockets was immature, rich in type III collagen, and had a low osteocyte density. Conclusions: The resorption of SCPC granules in 6 months was coordinated with better new bone formation than was observed in untreated sockets. SCPC is a resorbable bone graft material that enhances bone formation and maturation through its stimulatory effect on bone cell function.

• Journal of Periodontal and Implant Science
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• v.49 no.4
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• pp.258-267
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• 2019

Purpose: Increased bone regeneration has been achieved through the use of stem cells in combination with graft material. However, the survival of transplanted stem cells remains a major concern. The purpose of this study was to evaluate the viability of transplanted mesenchymal stem cells (MSCs) at an early time point (24 hours) based on the type and form of the scaffold used, including type I collagen membrane and synthetic bone. Methods: The stem cells were obtained from the periosteum of the otherwise healthy dental patients. Four symmetrical circular defects measuring 6 mm in diameter were made in New Zealand white rabbits using a trephine drill. The defects were grafted with 1) synthetic bone (${\beta}$-tricalcium phosphate/hydroxyapatite [${\beta}-TCP/HA$]) and $1{\times}10^5MSCs$, 2) collagen membrane and $1{\times}10^5MSCs$, 3) ${\beta}-TCP/HA+collagen$ membrane and $1{\times}10^5MSCs$, or 4) ${\beta}-TCP/HA$, a chipped collagen membrane and $1{\times}10^5MSCs$. Cellular viability and the cell migration rate were analyzed. Results: Cells were easily separated from the collagen membrane, but not from synthetic bone. The number of stem cells attached to synthetic bone in groups 1, 3, and 4 seemed to be similar. Cellular viability in group 2 was significantly higher than in the other groups (P<0.05). The cell migration rate was highest in group 2, but this difference was not statistically significant (P>0.05). Conclusions: This study showed that stem cells can be applied when a membrane is used as a scaffold under no or minimal pressure. When space maintenance is needed, stem cells can be loaded onto synthetic bone with a chipped membrane to enhance the survival rate.

• The Journal of the Korean dental association
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• v.57 no.3
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• pp.149-160
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• 2019

Atrophic alveolar ridge of maxillary anterior area is commonly observed after the extraction of teeth in patients with severely compromised periodontal disease, causing difficulties with implant placement. Successful esthetics and functional implant rehabilitation rely on sufficient bone volume, adequate bone contours, and ideal implant positioning and angulation. The present case report categorized the ridge augmentation techniques using guided bone regeneration (GBR) on the maxillary anterior site by Seibert classification. Case I patient presented for implant placement in the position of tooth #11. The alveolar ridge was considered a Seibert classification I ridge defect. Simultaneous implant placement and GBR were performed. Eight months after implantation, clinical and radiological examinations were performed. Case III patient presented with discomfort due to mobility of the upper maxillary anterior site. Due to severe destruction of alveolar bone, teeth #11 and #12 were extracted. After three months, the alveolar ridge was considered a Seibert classification III ridge defect. A GBR procedure was performed; implantation was performed 6 months later. Approximately 1-year after implantation, clinical and radiological examinations were performed. During the whole treatment period, healing was uneventful without membrane exposure, severe swelling, or infection in all cases. Radiographic and clinical examinations revealed that atrophic hard tissues and buccal bone contour were restored to the acceptable levels for implant placement and esthetic restoration. In conclusion, severely resorbed alveolar ridge of the maxillary anterior area can be reconstructed with ridge augmentation using the GBR procedure so that dental implants could be successfully placed.

• Journal of Periodontal and Implant Science
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• v.52 no.5
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• pp.370-382
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• 2022

Purpose: The aim of this study was to evaluate the preclinical results of 2 types of commercially available deproteinized bovine bone mineral (DBBM) when applied to alveolar bone defects in dogs. Methods: This study was conducted using 6 beagles. Alveolar defects in the mandible were formed and filled with 2 DBBMs produced by a similar procedure. Defects were randomly assigned to be filled using DBBM 1 or 2. All defects were covered with a collagen membrane and had a healing period of 12 weeks. After the dogs were sacrificed, histological, histomorphometric, and linear/volumetric analyses were performed. Results: Both DBBM groups showed similar histological findings, demonstrating that bone remodeling had occurred and new bone had formed. The residual bone particles were surrounded by newly formed vital bone. In the histomorphometric analysis, the ratio of the area of vital bone and residual bone substitute in DBBM 2 (38.18% and 3.47%, respectively) was higher than that of DBBM 1 (33.74% and 3.41%, respectively), although the difference was not statistically significant. There were also no statistically significant differences between both groups in linear and volumetric analyses using micro-computed tomography scans and digitized images of dental casts. Conclusions: In the present study, DBBM 1and 2, which were produced by similar processes, showed similar results in histological, histomorphometric, and volumetric analyses. Further studies are needed to identify more specific differences between the 2 DBBMs.