[Comparative study of iRoot SP and AH Plus on root canal sealing ability in periodontally compromised teeth].

Purpose: This study was aimed to compare the difference between iRoot SP and AH Plus on root canal sealing ability for teeth extracted due to severe periodontitis and explore whether the dentin tubule pathway plays an important role in the development of endodontic-periodontic lesions(EPL), in order to provide a theoretical basis for selection of proper time for root canal therapy and suitable root canal sealants in patients with EPL.

Methods: Fifty single-root anterior teeth extracted due to severe periodontitis were selected. The roots were completely debrided to remove the calculus, dental plaque and cementum.

[Short-term effect of ibuprofen on clinical indexes and cytokines in the gingival crevicular fluid of patients with severe chronic periodontitis].

Purpose: To explore the short-term effects of ibuprofen on clinical indexes and cytokines in the gingival crevicular fluid of patients with severe chronic periodontitis.

Methods: Twenty subjects with severe chronic periodontitis but otherwise healthy participated in the study and they were divided into two groups randomly. The patients in the experimental group took ibuprofen 300mg, bid for 5 days after scaling and root planing (SRP), while patients in the control group only underwent SRP.

[Effect of hypoxia on the expression of matrix metalloproteinase and tissue inhibitors of matrix metalloproteinase mRNA in human periodontal ligament fibroblasts in vitro].

Objective: To investigate the effect of hypoxia on the expression of matrix metalloproteinase (MMP) and tissue inhibitors of matrix metalloproteinase (TIMP) in human periodontal ligament fibroblasts (HPDLF).

Methods: HPDLF were cultured in α-minima essential medium (α-MEM) and subcultured at confluence. In the hypoxic groups, cells were incubated in a humidified atmosphere of 1%O(2), 5%CO(2), 94%N(2) at 37°C for 12, 24 and 48 h, respectively.

[Effects of EMPs on growth and attachment of human BMSCs].

Purpose: The present study is to evaluate the effects of enamel matrix proteins(EMPs) on the attachment, spreading and proliferation of human bone marrow stromal cells(hBMSCs) in vitro.

Methods: Human BMSCs were obtained from human bone marrow aspiration and cultured in DMEM medium with 10% fetal bovine serum (FBS). EMPs was added into medium in several concentrations (50,100, 200, 300 microg/ml) as experimental groups.

[Preliminary study on adult odontoblast culture in situ].

Purpose: To establish an in situ culture model of adult odontoblasts.

Methods: Thirty intact and healthy third molars freshly prepared from 20-30 year old individuals were randomly divided into three groups. Each group had 10 molars.

[Effects of enamel matrix proteins on the proliferation of human gingival epithelial cells in vitro].

Purpose: To evaluate the effect of enamel matrix proteins (EMPs) on the proliferation of human gingival epithelial cells in vitro.

Methods: EMPs were extracted from pig tooth germ by acetic acid. The gingival tissues cut off during gingivectomy were separated into two parts through Dispase II digestion and the epithelium part was cultured to acquire the gingival epithelial cells.

[Effects of enamel matrix proteins on the attachment,spreading and proliferation of porcine bone marrow stromal cells in vitro].

Purpose: The purpose of this study is to investigate the influence of enamel matrix proteins(EMPs) on the attachment, spreading and proliferation of cultured porcine bone marrow stromal cells (BMSCs).

Methods: BMSCs were obtained from porcine bone marrow aspiration and cultured in DMEM medium with 10% FBS.The third passage cells were exposed to various concentrations of EMPs (25,50,100 and 200microg /ml).

[The effect of bFGF on proliferation of periodontal fibroblast-like cells of dogs].

Objective: To evaluate the effects of basic fibroblast growth factor(bFGF) on proliferation of periodontal fibroblast-like cells in vivo.

Methods: A U-shaped osseous defect was produced on the buccal side of the mesial root. Four posterior teeth were conducted in four quadrants.