• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.4
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• pp.278-286
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• 2011

Introduction: This study examined the predictability of new bone formation in the pneumatized maxillary sinus using only fibrin-rich blocks with concentrated growth factors as an alternative to bone grafts. Materials and Methods: Maxillary sinus augmentation was performed in thirty-three patients with a deficient alveolar bone height (mean 3.9 mm). All patients were treated consecutively with sinus membrane elevation via the lateral window approach and panoramic radiograms and cone-beam computed tomograms were taken to evaluate the remaining bone height and the new bone formation in the maxillary sinus, before and after surgery. Four biopsy specimens were taken at the time of implant consolidation (after an average of five months healing) and were stained by H & E and Trichrome staining. Results: None of the patients had postoperative complications during implant consolidation. After an average of 5 months since sinus augmentation, newly formed bone was observed in all cases by a radiographic evaluation. In 4 biopsy samples, newly formed bone was observed along the floor of the replaced bony window. The osteoblast lining and well distinguished Osteocytes in the lacunas were observed in the newly formed bone. Of the 74 implants (4 different surfaced implants - resorbable blast media-surfaced (RBM), Hydroxyapatite (HA) coated, acid-etched, sintered porous-surfaced implant) placed, one RBM implant failed. The success rate was 98.6% after a mean of 15 months. Discussion: These results suggest that maxillary sinus augmentation using fibrin rich block with concentrated growth factors is a successful and predictable technique.

• The korean journal of orthodontics
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• v.50 no.2
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• pp.108-119
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• 2020

Objective: The primary objective of this study was to quantitatively analyze the bone parameters (thickness and density) at four different interdental areas from the distal region of the canine to the mesial region of the second molar in the maxilla and the mandible. The secondary aim was to compare and contrast the bone parameters at these specific locations in terms of sex, growth status, and facial type. Methods: This retrospective cone-beam computed tomography (CBCT) study reviewed 290 CBCT images of patients seeking orthodontic treatment. Cortical bone thickness in millimeters (mm) and density in pixel intensity value were measured for the regions (1) between the canine and first premolar, (2) between the first and second premolars, (3) between the second premolar and first molar, and (4) between the first and second molars. At each location, the bone thickness and density were measured at distances of 2, 6, and 10 mm from the alveolar crest. Results: The sex comparison (male vs. female) in cortical bone thickness showed no significant difference (p > 0.001). The bone density in growing subjects was significantly (p < 0.001) lower than that in non-growing subjects for most locations. There was no significant difference (p > 0.001) in bone parameters in relation to facial pattern in the maxilla and mandible for most sites. Conclusions: There was no significant sex-related difference in cortical bone thickness. The buccal cortical bone density was higher in females than in males. Bone parameters were similar for subjects with hyperdivergent, hypodivergent, and normodivergent facial patterns.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.623-634
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• 1995

Periodontitis is characterized by gingival inflammation and results in periodontal pocket formation with loss of the supporting alveolar bone and connective tissue around the teeth. Therapeutic modalities should therefore aim not only at eliminating the gingival inflammatory process and preventing the progression of periodontal disease but also at reestablishing and regenerating the periodontal tissue previously lost to the disease. To achieve periodontal regeneration, progenitor cells must migrate to the denuded root surface, attach to it, proliferate and mature into an organized and functional fibrous attachment apparatus. Likewise, progenitor bone cells must also migrate, proliferate, and mature in conjunction with the regenerating periodontal ligament. Significant advances have been made during the last decade in understanding the factors controlling the migration, attachment and proliferation of cells. A group of naturally occuring molecules known as polypeptide growth factors in conjunction with certain matrix proteins are key regulators of these biological events. Of these, the fibroblast growth factor(FGF), platelet-derived growth factor(PDGF) , insulin like growth factor(CIGFs), transforming growth factor(TGFs), epidermal growth factor(EGF) and bone morphogenetic growth factor(BMPs) apper to have an important role in periodontal wound healing. The purpose of this study was to determine the effects of BMP on periodontal ligament cells. Human periodontal ligament cells were cultured from extracted tooth for non-periodontal reason. Cultured periodontal ligament cells were treated with BMP. Cellular activities were determined by MTT(3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay and ALP(alkaline phosphatase) activity. The results were as follows ; Regardless of cultured time, cellular activities were stimulated by BMP. Also, BMP greatly increased alkaline phosphatase(ALP) in periodontal ligament cells. These results suggest that BMP not only have no cytotoxic effect on periodontal ligament cells, but also have osteogenic stimulatory effect on periodontal ligament cells.

• The korean journal of orthodontics
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• v.18 no.2
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• pp.343-366
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• 1988

Craniofacial complex is influenced by numerical skeletal elements. Though the analysis of growth change has been done by various analytical methods, it was dependent on any method of registration and superimposition, based on reference plane and reference point. However, the craniofacial growth is composed of a number of local growth elements. Therefore, it will be necessary to use a clinically useful method for estimating craniofacial skeletal growth independently. The author analysed longitudinal cephalometric roentgenogram of 15 Korean males and 15 Korean females aged from 6 to 12 years by the finite element method and results were as follows : 1. The finite element method for craniofacial skeletal complex and soft tissue made it possible to analyze the independent local growth. 2. Regression equations from the value of each strain will make it possible to predict the craniofacial growth. 3. The growth of anterior cranial base was different from that of other facial bone. 4. The growth of posterior cranial base influenced the growth of upper pharyngeal region, midfacial region, maxilla and posterior region of mandible. 5. The growth of maxillary complex was vertical rather than horizontal. 6. The growth direction of ramus, mandibular body, alveolar bone was various. 7. The relation between hard tissue and soft tissue by finite element method was variant.

• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.341-356
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• 1995

The purpose of this study was to evaluate the effect of demineralized freeze dried bone and demineralized bone gel with guided tissue regeneration treatment around titanium implants with dehisced bony defects and also evaluate space maintaining capacity of demineralized bone gel type and DFDB powder type under e-PTFE membrane. In 3 Beagle dogs, mandibular premolar was extracted and four peri-implant osteotomies were formed for dehiscence. After insertion of implants, the four peri-implant defects were treated as follows. 1) In control group. no graft material and barrier membrane were applied. 2) In experimental group.1, the site was covered only with the e-PTFE membrane. 3) In experimental group 2,received DFDB powder and covered by the e-PTFE membrane. 4) In experimental group 3, demineralized bone gel and e-PTFE membrane were used. By random selection, animals were sacrificed at 4, 8, 12 weeks. The block sectioned specimens were prepared for decalcified histologic evaluation(hematoxylin and eosin staining) and undecalcified histologic evahiation(Von Kossa's and toluidine blue staining) with light microscopy. The results of this study were as follows. 1) In control group, there was a little new bone formation and connective tissue was completely filled in the defect area. 2) Experimental group 1 showed lesser quantity of bone formation as compared to the bone grafted group. Thin vertical growth of new bone formation around implant fixture was shown. 3) Experimental group 2 showed thick bucco-lingual growth of new bone formation and grafted bone particles were almost resorbed in 12 week group. 4) In experimental group 3, most grafted bone particles were not resorbed in 12 week group and thick bucco-lingual bone formation was shown in dehisced defect base area. 5) There was no remarkable differences in space making capacity and new bone formation procedure between demineralized freeze-dried bone powder type and demineralized bone gel type.

• Journal of Periodontal and Implant Science
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• v.31 no.2
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• pp.421-436
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• 2001

Transforming growth $factor-{\beta}(TGF-{\beta})$is a polypeptide biologic mediator considered to play a role in promoting bone formation in bony defect area. The purpose of this study was to examine the effect of $TGF-{\beta}$ to the periodontal regeneration of class III furcation defect in dogs. Classs III furcation defects were surgically created on the third and the fourth premolars bilaterally in the mandibles of eight mongrel dogs. Experimental periodontitis were induced by placing small cotton pellets into the created defects for 3 weeks. Experimental sites were divided into 4 groups according to the treatment modalities: Group I-Surgical debridement only; Group II-allogenic demineralized freeze dried bone grafting; Group III-allogenic demineralized freeze dried bone soaked in $TGF-{\beta}(4ng/10{\mu}l)$grafting; Group IV-allogenic demineralized freeze dried bone soaked in $TGF-{\beta}(20ng/10{\mu}l)$ grafting. The animals were sacrificed in the 8th week after periodontal surgery and the decalcified and undecalcified specimens were for histological and histometric examination. Although no significant differences was seen in the length of epitheial growth and connective attachment, group III showed the least apical migration among treatment groups. The amount of bone repair was significantly greater in group III, IV compared to group I and group II. New attachment formation was significantly greater in group III and group IV compared to group I and group II. These results suggest the allogenic demineralized freeze dried bone with $TGF-{\beta}$ in class III furcation defect has the potentiality of promoting alveolar bone formation and periodontal regeneration.

• Journal of Periodontal and Implant Science
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• v.32 no.1
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• pp.89-112
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• 2002

The earliest reports of the use of electrical energy to directly stimulate bone healing seem to be in 1853 from England, the techniques involved the introduction of direct current into the non-united fracture site percutaneously via metallic needles, with subsequent healing of the defect. One endpoint of the periodontal therapy is to generate structure lost by periodontal diseases. Several procedural advances may support regeneration of attachment, however, regeneration of alveolar bone does not occur consistently. Therefore, factors which stimulate bone repair are areas for research in periodontal reconstructive therapy. Effects of cytokines or growth factors on bone repair are examples of such areas. Another one is electrical current which occurs in bone naturally, so that such bone may be particularly susceptible to electrical therapy. The purposes of this study were to observe the effects of electrical stimulation on the normal periodontium, to determine whether the electricity is the useful means for periodontal regeneration or not. Forty rats weighted about 100 gram were used and divided into 4 groups, the first group, there was no electrical stimulation with the connection of electrodes only. In the second group, there was stimulated by the 10 mA during 10 minutes per a day, in the third group was stimulated by the 25 mA , and the fourth by the 50 mA. At 3, 5, 10 and 15 days post-appliance , two rats in each group were serially sacrificed. and the maxillae and the mandible processed to paraffin, and the specimens were prepared with Hematoxylin-Eosin stain for the light microscopic evaluation. The results of this study were as follows : 1. There was the distinct reversal line on the lingual alveolar crest, whereas a little changes in the labial alveolarcrest to the duration and amount of currents. 2. In 50 mA group, the cells were highly concentrated at the apex of anterior teeth, and was observed the necrotic tissue. In posterior root apex, the hypercementosis was appeared, and newly formed cementum layer has been increased continuously with the time. 3. The periodontal ligament fiber and Sharpey's fiber were arranged in order, and the bone trabeculae were increased as the experiment proceeded by, relatively the bone marrows were decreased. 4. In the pulp tissue, the blood vessels were increased with blood congestion in the experimetal specimens remarkably, and the dentinal tubules were obstructed . 5. The osteoblasts in alveolar bone proper had been showed highly activity, and also observed the formation of bone trabeculea. In the conclusion, it was suggested that the electrical stimulation has influence on the periodontium and the pulp tissue. However, there might be the injurious effects.

• The korean journal of orthodontics
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• v.39 no.3
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• pp.185-198
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• 2009

Tooth anklylosis is defined as the adhesion state of alveolar bone to dentin or cementum. Trauma, disturbed metabolic disease, and congenital disease have been given as etiologic factors. Complications of tooth ankylosis are tipping of the neighboring teeth, space loss, and supraeruption of the opposing teeth. Particularly if dental ankylosis occurs in maxillary incisors of a growing child, the ankylosed tooth can not move vertically with subsequent disturbance in vertical growth of the alveolar process. With an appropriate treatment approach, an esthetic condition must be achieved especially in the maxillary anterior region. In this report, two cases are presented which were treated by the surgical repositioning method. One is treated by alveolar bone distraction osteogenesis which used a tooth-borne type distraction device and the other by single tooth osteotomy.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.2
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• pp.252-259
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• 2010

Trauma commonly leads to ankylosis for the tooth whose periodontal ligaments have been injured. In growing patients, an ankylosed tooth can disrupt alveolar development, resulting in infraocclusion of the affected tooth. Consequently, this causes aesthetic problems during adolescence, interferes with prosthetic treatment due to the inclination of adjacent teeth, and complicates orthodontic dental movement. When the infraoccluded ankylosed tooth is extracted, a considerable amount of alveolar bone is lost, especially in the maxillary anterior region. Moreover, depression of the thin buccal alveolar bone compromises aesthetic restoration. In order to prevent alveolar bone loss, the ankylosed tooth should be treated by decoronation. In the present study, the traumatically injured maxillary incisors of 9-year-old and 10-year-old patients that present infraocclusion accompanied by ankylosis were treated with decoronation procedures. Decoronation procedures were performed when the affected teeth were 2-3 mm below relatively to the adjacent teeth. Moreover, the patients were treated before they get to 16 years old considering the maximum growth peak of the korean adolescents. As the results, there are favorable clinical results associated not only with preservation of horizontal alveolar volume but also with increase in vertical alveolar height after decoronation in growing individuals.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.2
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• pp.155-161
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• 2012

Platelet-rich fibrin (PRF) is a strong but flexible fibrin including a enrich platelet which contain growth factors and cytokines. PRF can be made very simply and requires no artificial additives unlike platelet-rich plasma. While PRF is remodeled and released in the tissue, this induces cell growth, vascularization, collagen synthesis, osteoblast differentiation and an anti-inflammatory reaction. Taking advantage of these functions, PRF can stimulate regeneration of bone and soft tissue in a diverse number of ways during the course of hemostasis, wound coverage, preservation, and reconstruction of alveolar bone. Moreover, the use of PRF to improve bone regeneration has become a recent technique in implantology. In this study, through a literature review of PRF's existing clinical applications, we classified a range of potential PRF oral and maxillofacial surgery applications including preservation of extraction sockets, guided bone graft, sinus lift, dressing and periodontal treatment. This trial gave us chance to confirm the usefulness of PRF. Recently, updated clinical studies results concerning skin and tendon wound healing have become available. These results suggest that the usage of RPF will gradually expand.