Periodontal therapy has dealt primarily with attempts at arresting progression of disease, however, more recent techniques have focused on regenerating the periodontal ligament having the capacity to regenerate the periodontium. The effect of chitosan, a carbohydrate biopolymer extracted from chitin, on periodontal ligament regeneration is of particular interest. The purpose of this study was to evaluate the effect of chitosan on the expression of extracellular matrix proteins in primary rat calvarial cells in vitro. In the control group, cells was cultured with BGJb media. In the experimental groups, cells were cultured with chitosan in concentration of 0.01, 0.1, 1.0 and 2.0 mg/ml. Then each group was characterized by examining alkaline phosphatase activity at 3 and 7 days, and the ability to produce mineralized nodules of rat calvarial cells at 14 and 21 days. Synthesis of type I collagen (COL-I), osteocalcin (OCN), bone sialoprotein (BSP) was evaluated by RT-PCR at 14 days. The results were as follows: 1. Alkaline phosphatase activity was significantly higher in the concentration of chitosan 0.01mg/ml, 0.1mg/ml and 1.0mg/ml compared to control (p<0.05). 2. The percentage of mineralized bone nodule was more in the concentration of chitosan 0.1mg/ml and 1.0 mg/ml than the control. 3. At 14 day culture, the expression of OCN was increased by chitosan in concentration of 1.0 mg/ml and 2.0 mg/ml. These results suggested that chitosan in concentration of 0.1 and 1.0 mg/ml stimulate the extracellular matrix of primary rat calvarial cells and may facilitate the formation of bone.
Alkaline Phosphatase ; Animals ; Biopolymers ; Bone Matrix* ; Chitin ; Chitosan* ; Collagen Type I ; Extracellular Matrix ; Extracellular Matrix Proteins ; Integrin-Binding Sialoprotein ; Osteocalcin ; Periodontal Ligament ; Periodontium ; Rats* ; Regeneration

The effect of chitosan, a carbohydrate biopolymer extracted from chitin, on periodontal regeneration is of particular interest. The purpose of this study was to evaluate the effect of chitosan on primary rat calvarial cells in vitro, with special focus on their proliferative properties by cell activity and the amount of total protein synthesis. The experimental groups were cultured with chitosan in concentration of 0.01, 0.1, 1.0, 2.0 and 5.0 mg/ml for MTT assay. In the experimental groups, cells were cultured with chitosan in concentration of 0.01, 0.1, 1.0 and 2.0 mg/ml. Each group was characterized by examining alkaline phosphatase activity at 3 and 7 days and the ability to produce mineralized nodules of rat calvarial cells at 14 and 21 days. The results were as follows: 1. The cell activity was not reduced in the concentration of 0.01~1.0 mg/ml whereas the cell activity was reduced in the concentration of 5.0 mg/ml than the control at day 1 and 3 (p<0.05). 2. Primary rat calvarial cells treated with chitosan in the concentration 0.01 mg/ml and 0.1 mg/ml showed more protein synthesis than the control at day 3 (p<0.01). But primary rat calvarial cells treated with chitosan showed more protein synthesis than in control but they didn't have statistically difference among groups at day 7. 3. At 3 and 7 days, alkaline phosphatase activity was significantly increased in the concentration of 0.01 mg/ml. 0.1 mg/ml and 1.0 mg/ml (p<0.05). 4. The percentage of mineralized bone nodule was more in the concentration of chitosan 0.1 mg/ml and 1.0 mg/ml than the control. These results suggested that chitosan has a positive effect on the bone formation of primary rat calvarial cells in the concentration of 0.1 mg/ml and 1.0 mg/ml.
Alkaline Phosphatase ; Animals ; Biopolymers ; Chitin ; Chitosan* ; Osteogenesis ; Rats* ; Regeneration

No abstract available.
Alendronate* ; Animals ; Diphosphonates ; Rats*

Helicobacter pylori(H. pylori) has been associated with the cause of chronic gastritis, peptic ulcers and gastric cancer. Although it may be transmitted through the oral cavity, it is unknown whether the oral cavity acts as a reservoir of H. pylori. The purpose of this study was to investigate the mode of detection of H. pylori in oral cavity of adult periodontitis patients with plaque and periodontal pocket which atmosphere is grown well H. pylori. We analysed detection rate of H. pylori in saliva and subgingival plaques of 17 adult periodontitis patients without symptoms of gastroduodenal disease by nested PCR. Samples tested comprised saliva and subgingival plaques from central incisor, 1st premolar and 1st molar. H. pylori DNA was not identified in saliva from all patients. The detection rate in subgingival plaque from incisors, premolars and molars was 5.9%, 5.9% and 17.7%, respectively. In conclusion, the dental plaque and periodontal pocket (especially, of molars) in adult periodontitis can be favorable reservoir of H. pylori and may be the source of infection and transmission of H. pylori.
Adult* ; Atmosphere ; Bicuspid ; Chronic Periodontitis* ; Dental Plaque ; DNA ; Gastritis ; Helicobacter pylori* ; Helicobacter* ; Humans ; Incisor ; Molar ; Mouth ; Peptic Ulcer ; Periodontal Pocket ; Polymerase Chain Reaction ; Saliva* ; Stomach Neoplasms

The purpose of this study is to evaluate the regenerated bone histollogically using titanium reinforced ePTFE(TR-ePTFE) membrane and to investigate cell occlusiveness, wound stabilization and tissue integration of TR-ePTFE membrane. Adult male rabbits (mean BW 2kg) and TR9W (W.L.Gore&Associate.INC,USA) were used in this study. Intramarrow penetration defects were surgically created with round carbide bur(HP long #6) on calvaria of rabbits. TR-ePTFE membrane was applied to defect. Then guided bone regeneration was carried out using TRePTFE membrane and resorbable suture. At 2,4,8,12 weeks after the surgery, animals were sacrificed. Nondecalcified specimens were processed for histologic analysis. The result and conclusion of this study were as follows: 1. TR-ePTFE membrane had good ability of biocompatibility and cell occlusiveness. 2. space making for guided bone regenerayion was good at TR-ePTFE membrane. 3. Tissue integration was not good at TR-ePTFE membrane. So, wound stabilization was not good. 4. At 8 weeks, 12 weeks after GBR procedure, bone formation was seen. From the above results, TR -ePTFE membrane fixed tightiy on alveolar bone might be recommended for the early bone formation.
Adult ; Animals ; Bone Regeneration ; Humans ; Male ; Membranes* ; Osteogenesis ; Rabbits ; Skull ; Sutures ; Titanium* ; Wounds and Injuries

The present study was performed to evaluate histomorphological difference in various surface-treated implants in beagle. Implants(Implantium(R), Dentium Co. Korea) with pure titanium machined surface, acid treated surface, and Al2O3(50~100micrometer)blasted with acid treated surface were used in this study. All mandibular premolars of 1.5~2 year old male beagle dogs were extracted. At 3 months after extraction, the implants(phi 4mm, l6mm) were installed. The beagle were sacrificed at 1, 3 months after installation and then tissues including implants were prepared for non-decalcified specimens. These specimens were analyzed comparatively under light microscope. The results of this study were as follow 1. Higher rate of osseointegration were showed in the Al2O3(50~100micrometer)blasted with acid-treated surface. 2. Increased osseointegration were showed in the Al2O3(50~100micrometer)blasted with acidtreated surface with time. 3. Higher maturation of integration were showed in the Al2O3(50~100micrometer)blasted with acid-treated surface. In conclusion, surface treatment of Al2O3blasted with acid might be considered to shorten healing time and improve success rate as increasing contact of implant and bone.
Animals ; Bicuspid ; Dogs ; Humans ; Male ; Osseointegration* ; Titanium

The present study evaluated the effects of guided tissue regeneration using xenograft material(deproteinated bovine bone powder), with and without biodegradable membrane in beagle dogs. Contralateral fenestration defects (6 x 4 mm) were created 4 mm apical to the buccal alveolar crest of maxillary premolar teeth in 5 beagle dogs. Deproteinated bovine bone powders were implanted into fenestration defect and one randomly covered biodegradable membrane (experimental group). Biodegradable membrane was used to provide GTR. Tissue blocks including defects with soft tissues which were harvested following four & eight weeks healing interval, prepared for histo-phathologic analysis. The results of this study were as follows. 1. In control group, at 4 weeks after surgery, new bony trabecular contacted with interstitial tissue and osteocytes like cell were arranged in new bony trabecule. Bony lamellation was not observed. 2. In control gruop, at 8 weeks after surgery, scar-like interstitial tissue was filled defect and bony trabecule form lamellation. New bony trabecular was contacted with interstitial tissue but defect was not filled yet. 3. In experimental group, at 4 weeks after surgery, new bony trabecular partially recovered around damaged bone. But new bony trabecule was observed as irregularity and lower density. 4. In experimental group, at 8 weeks after surgery, lamella bone trabecular developed around bone cavity and damaged tissue was replaced with dense interstitial tissue. In conclusion, new bone formation regenerated more in experimental than control groups and there was seen observe more regular bony trabecular in experimental than control groups at 4 weeks after surgery. In control group, at 8 weeks after surgery, the defects was filled with scar-like interstitial tissue but, in experimental group, the defects was connected with new bone. Therefore xenograft material had osteoconduction but could not fill the defects. We thought that the effective regeneration of periodontal tissue, could be achieved using GTR with biodegradable membrane.
Animals ; Bicuspid ; Bone Regeneration ; Dogs* ; Furcation Defects* ; Guided Tissue Regeneration ; Heterografts ; Membranes* ; Osteocytes ; Osteogenesis ; Powders ; Regeneration* ; Tooth

No abstract available.
Cell Differentiation ; Cell Proliferation ; Fibronectins* ; Osteoblasts* ; Titanium

Epithelial-mesenchymal interaction plays a important role in cell growth and differentiation. This interaction is already well known to have an importance during the organ development as well as cell growth and differentiation. However, in vitro experimental model is not well developed to reproduce in vivo cellular microenvironment which provide a epithelial-mesenchymal interaction. Because conventional monolayer culture lacks epithelial-mensenchymal interaction, cultivated cells have an morphologic, biochemical, and functional characteristics differ from in vivo tissue. Moreover, it's condition is not able to induce cellular differention due to submerged culture condition. Therefore, the aims of this study were to develop and evaualte the in vitro experimental model that maintains epithelial-mesenchymal interaction by organotypic raft culture, and to characterize biologic properties of three-dimensionally reconstituted oral keratinocytes by histological and immunohistochemical analysis. The results were as follow; 1. Gingival keratinocytes reconstituted by three-dimensional organotypic culture revealed similar morphologic characteristics to biopsied patient specimen showing stratification, hyperkeratinosis, matutation of epithelial architecture. 2. Connective tissue structure was matured, and there is no difference during stratification period of epithelial 3-dimensional culture. 3. The longer of air-exposure culture on three-dimensionally reconstituted cells, the more epithelial maturation, increased epithelial thickness and surface keratinization 4. In reconstitued mucosa, the whole epidermis was positively stained by anti-involucrin antibody, and there is no difference according to air-exposured culture period. 5. The Hsp was expressed in the epithelial layer of three-dimensionally cultured cells, especially basal layer of epidermis. The change of Hsp expression was not significant by culture stratification. 6. Connexin 43, marker of cell-cell communication was revealed mild immunodeposition in reconstitued epithelium, and there is no significant expression change during stratification. These results suggest that three-dimensional oragnotypic co-culture of normal gingival keratinocytes with dermal equivalent consisting type I collagen and gingival fibroblasts results in similar morphologic and immunohistochemical characteristics to in vivo patient specimens. And this culture system seems to provide adequate micro-environment for in vitro tissue reconstitution. Therefore, further study will be focused to study of in vitro gingivitis model, development of novel perioodntal disease therapeutics and epithelial-mensenchymal interaction.
Cells, Cultured ; Cellular Microenvironment ; Coculture Techniques ; Collagen Type I ; Connective Tissue ; Connexin 43 ; Epidermis ; Epithelium ; Fibroblasts* ; Gingivitis ; Humans ; Keratinocytes* ; Models, Theoretical ; Mucous Membrane

The purpose of this study is to evaluate histologically the tissue response and resorption of various nonresorbable and resorbable suture materials used for periodontal surgery, using a subcutaneous model on the dorsal surface of the rat. In this study, 10 Sprague-Dawley male rats (mean BW 150gm) were used and the commercially available materials included polyglactin 910, pain gut, nylon, e-PTFE. Animals were sacrificed at 3 days, 1, 2 and 4 weeks after implantation of various nonresorbable and resorbable suture materials. Specimens were prepared with Hematoxylin-Eosin stain for light microscopic evaluation. The results of this study were as follows: 1. Resorption : The resorption of plain gut was showed at 1 week after implantation, was lost their structure and almost resorbed at 4 weeks. The resorption of polyglactin 910 was started at 2 weeks and slowly absorbed untill 4 weeks. 2. Tissue response : Plain gut showed persistent and severe inflammatory reactions from 3 days to 4 weeks. Polyglactin 910, e-PTFE and nylon showed mild inflammatory reactions. Suture material should be biocompatible and be able to be functioned until tissue tensile strength reaches maximum level. In this study, polyglactin 910, nylon and e-PTFE are considered to be proper suture materials for periodontal surgery.
Animals ; Humans ; Male ; Nylons ; Polyglactin 910 ; Rats* ; Rats, Sprague-Dawley ; Sutures* ; Tensile Strength ; Wound Healing