Altan Doğan

Gazi University, Ankara, Ankara, Turkey

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Publications (3)8.51 Total impact

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    ABSTRACT: The purpose of this study was to assess the seeding of fibroblast-like cells to promote periodontal healing in artificial fenestration defects in a dog. Fibroblast-like cells were cultured by incubating regenerated periodontal ligament tissue, that had been surgically taken, underneath a Teflon membrane. Fenestration defects were surgically induced on the maxillary canine and first molar teeth at a spacing of 5 to 5 mm. Passage 4 cells (2 x 10(5) cells) in autologous blood coagulum were placed on root surfaces in two defects; the remaining two defects were used as controls. Healing was evaluated histomorphometrically on postoperative day 42. The main periodontal healing pattern consisted of connective tissue adaptation in three of the four specimens including one control, with cementum formation at 9-12%; one control specimen that exhibited 100% cementum formation. New bone formation was greater in the cell-seeding group (84%) compared with control (39%). In the cell-seeding group, one specimen exhibited total regeneration of bone (100%); however, the connective tissue located between newly formed bone and the root surface was observed to adapt to the dentin surface, with limited cementum formation. Seeding of cells from periodontal ligament may be promising to promote periodontal regeneration, but needs to be investigated in further studies.
    Tissue Engineering 01/2004; 9(6):1189-96. · 4.25 Impact Factor
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    ABSTRACT: The regeneration of periodontal supporting tissues lost as a result of disease could be accomplished by repopulating the exposed root surfaces with cells originating from periodontal ligament. Thus, we aimed to assess the seeding of cells derived from regenerated periodontal ligament (RPL) to promote the regeneration in artificial furcation defects of a dog. The fibroblast-like cells were obtained by incubating the explants of RPL tissue taken under a teflon (E-PTFE) membrane. Class II furcation defects were induced on the second and fourth mandibular premolars. Control defects were also included on the contralateral side. A suspension of the fourth passage cells (2 x 10(5) cells) in 0.5 mL of autologous blood coagulum was placed over each furcation area. The healing was histomorphometrically evaluated at the 42nd day postoperatively and expressed as percentage. The healing by new connective tissue attachment with cementum formation was found 75% in the cell-seeding defects whereas, it was 71% in controls. Bone formation was found to fill 51% of furcation defects; however, it was 35% of the defects in the control sites. In this pilot study, we suggested that regeneration of furcation defects by cell-seeding technique may be useful, but further studies are needed to determine the outcome of the procedure.
    Tissue Engineering 05/2002; 8(2):273-82. · 4.25 Impact Factor
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    ABSTRACT: Folic acid (FA), that is required for the integrity of gingival tissues, was found to decrease in patients using phenytoin (PHT). Interleukin-1 beta (IL-1beta) was reported to enhance the extracellular matrix synthesis in fibroblasts. The purpose of this study was to assess the role of FA supplementation on PHT-induced overgrowth by investigating its effect on IL-1beta production of human gingival fibroblasts induced by tumor necrosis factor alfa (TNFalpha) in cell culture. PHT (20 microg/ml), FA (20 or 40 ng/ml) + PHT, PHT + TNF (10 ng/ml), FA (20 or 40 ng/ml) + PHT + TNF, or only culture medium (control) was added to 24-well plates containing fibroblasts. After an incubation period of 72 h, culture medium and cells were harvested separately. Then, IL-1beta levels in cell lysate were measured using enzyme-linked immunosorbent assay. The cellular IL-1beta level in the PHT group was 1 pg/ml. In PHT + 20 or 40 ng/ml FA-added cultures, the results obtained respectively were 0.8 and 0.7 pg/ml, whereas the control group value was 0.7 pg/ml. IL-1beta level was 4 pg/ml in the cultures that PHT and TNFalpha were applied simultaneously (P < 0.05). When PHT and either 20 or 40 ng/ml FA were simultaneously added into TNFalpha-induced cultures, the IL-1beta levels were 1.8 and 1.3 pg/ml, respectively. IL-1beta level in gingival tissues might play a role in PHT-induced overgrowth by increasing in the gingival tissues, and FA application might play a role in decreasing gingival tissues. However, further studies are needed for a more complete understanding of PHT-induced gingival overgrowth at the cellular level.
    Journal of Oral Science 12/2001; 43(4):255-60.