Clinical study on therpeutic effects of Guided tissue regeneration by Nanogide-C(R) and Biomesh(R) in furcation defects / 대한치주과학회지

This study was designed to compare the effects of treatment using chitosan membrane (Nanogide-C(R)) resorbable barrier with control treated by polylactic acid/polylacticglycolic acid membrane(PLA/PLGA membrane, Biomesh(R)). 44 furcation defecs from 44 patients with class 2 furcation degree were used for this study, 22 sites of them were treated by chitosan membrane as experimental group and 22 site were treated by PLA/PLGA membrane as control group. Clinical parameters including probing depth, gingival recession, attachment level and radiographic examination were evlauated at base line, 1 month, 2 month and 3 month. after surgery. Statistical test used to analyze these data included paired t-test, one way ANOVA. The results are as follows : 1. Probing depth was significanlly decreased in the two group and there were significant differences between groups(p<0.05). 2. Gingival recession was not significanlly increased in the two group and there were no significant differences between groups(p<0.05). 3. Loss of attachment was statistically decreased in the two group and there were no significant differences between groups(p<0.05). 4. Horizontal bone level was significanlly increased in the two group and there were significant differences between groups(p<0.05). On the basis of these results, chitoans resorbable membrane has similar potential to PLA/PLGA membrane in GTR for furcation defect.

Effects of a xenographic bovine bone on the bone mineralization in human fetal osteoblasts / 대한치주과학회지

The ultimate goal of periodontal therapy is to promote the regeneration of lost periodontal tissue, there have been many attempts to develop a method to achieve this goal, but none of them was completely successful. The purpose of this study is to evaluate the effects of Bio-Oss(R) on alkaline Phosphatase (ALP) activity in human fetal osteoblasts (hFOB1). The results of this study were as follows, in ALP Activity, 100 microgram/ml Bio-Oss(R) treated group showed significantly increased value than negative control group, but positive group(10(-7) M dexamethasone treated group) showed the highest ALP activity at 3 day. In mineralization assay, numerous mineralized nodules were identified as darkly stained spots in 100 microgram/ml Bio-Oss(R) treated group than two control groups, whereas a small number of mineralized nodules were showed in the positive control. ALP may relate to the initial phase of bone nodule formation. On the basis of these results, this study showed Bio-Oss(R) is capable of accelerating new bone formation through hFOB1 differentiation in vitro.

Effects of Cervi Parvum Cornu on Cell Cycle Regulation in Human Fetal Osteoblasts / 대한치주과학회지

Recently, many natural medicines, whose advantages are less side effects and possibility of long-term use, have been studied for their capacity, their anti-bacterial and anti-inflammatory effects and regenerative potential of periodontal tissues. Cervi Parvum Cornu(CPC) have been traditionally used as an hale, growth, hematogenous, anti-aging, back pain in Eastern medicine. The purpose of present study was to investigate the effects of CPC extract on cell cycle progression and its molecular mechanism in human fetal osteoblasts. CPC extracts (10 microgram/ml) increased cell proliferation in the human fetal osteoblasts as compared to non-supplemented control. There was no significant change in the G1 and S phase, but a increase in the G2/M phase in 10 microgram/ml and 100 microgram/ml of CPC extracts group as compared to non-supplemented control. The protein expression of cyclin E, cdk 2, cyclin D, cdk 4, and cdk 6 was higher than that of control group. The level of p21 was lower than that of control. But that of pRb and p16 was not distinguished from control. These results indicate that the increase of cell proliferation by CPC extracts may be due to the increased expression of cyclin E , cdk 2, cyclin D, cdk 4 and cdk 6, and the decreased expression of p21 in human fetal osteoblasts .

Establishment of Immotalized Human Gingival Fibroblast Cell Lines / 대한치주과학회지

Human gingival fibroblasts have proven to useful as a species specific cell culture system in various system on periodontal disease and regeneration. However, their use is limited, since they are hard to obtain and lifespan is short due to replicative senescence. To overcome these disadvantages, we transfected primary human gingival fibroblasts by the E6 and E7 genes of the Human papilloma virus(HPV) 16. The full length of HPV 16 E6 and E7 was cloned from the pBR322 into BamH1 and Sal I of a pBabe vector including hygromycin B resistance. Before pBabeE6/E7 plasmid transfection, peak 8 GFP including G418 resistance was transfected into primary GF to check the transfection efficency. PBabe E6/E7 plasmid was transfected using Lipofectamine plus following manufacter's instruction into primary normal human gingival fibroblasts in 60mm dishes with FBS free DMEM. After 2 days of transfection, the cells were treated with hygromycin for 2 weeks until the transfected control cells died. The resulting hygromycin resistant colonies were pooled, and clonned, and sucessful transfection was established for immortalized gingival fibroblast cell lines. Immoralized GF cells showed stellate shape, that is similar to that of orange grains, and more rapid growth and higher proliferation than that of primary gingival fibroblasts. This cell lines overcame crisis and could be cultured over 30 subcultured, could be use for three dimentional culture, epithelial-mesenchymal interaction study.

Change of Stratification of Three Dimensional Culture by Gingival Keratinocytes & Fibroblasts / 대한치주과학회지

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.