Objective　To investigate the methods of isolation, cultivation and amplification of Bone marrow mesenchymal stem cells (BMSCs) and the feasibility of inducing BMSCs to differentiate to myofibroblast with exogenous Transforming growth factor-1 (TGF-β1) in vitro to provide the theory for jaw fibrosis induced by radiation .Methods The Bone marrow mesenchymal stem cells (BMSCs) were obtained from rats’ Bone marrow of femur，and the isolation and cultivation were processed by all cultivation；The passage Ⅲ cells were exposed to two kinds of defined mediums for phenotype differentiation. After two weeks of induction, the morphological change of cells was observed in Microscope; Real-time PCR was used to detect cells’ gene expression；the identification of α-SMA and collagenous fiber was pursued by immunohistochemistry．Results　Bone mesenchymal stem cells could be isolated from bone marrow tissue of the rat femoral; the morphology of spindle and shuttle was similar to fibroblast; after directional induction by TGF-β1, the cells showed the characteristics of Myofibroblasts (α-SMA +) accompanied with the increase of COLⅠ、COLⅢ and α-SMA. Conclusion　Bone marrow mesenchymal stem cells, which have stable biological characteristics, can be isolated from the rat femoral bone marrow tissue; TGF-β1 can induce BMSCs to differentiate to Myofibroblast directly, which provides the theory for fibrosis of jaws induced by radiation in vitro.

Objective To study the apoptosis activity of the basal cells during the growth and development of rats, and iNOS, Fas expression and the regularities of distribution in this process. Methods SPF grade SD male rats were divided into seven groups (4, 8, 16, 32, 48, 64,128d). TUNEL method and immunohistochemical S-ABC method were used to detect temporal and spatial characteristics of the apoptotic pathways and correlation between each way. Results Yellow fluorescent TUNEL cartilage cell apoptosis can be seen in each group. 4d,8d,16d after birth, a small amount of cell apoptosis appeared in the hypertrophic zone and the junctional zone of the synchondrosis and the number of cells increased with the time went by. iNOS mainly expressed in the quiescent zone and the proliferative zone. Fas existed in almost every period of each layer of cartilage joint and expressed more in the hypertrophic zone and the junctional zone. Conclusion The growth and development of synchondrosis is closely linked with chondrocyte apoptosis. There were two pathways in the synchondrosis. Fas pathway plays a leading role while mitochondrion pathway is more significant to the growth in quiescent zone and proliferative zone.

［Abstract］ 0bjective To explore the influence of TNF-α on the expression of MMPs and the ability of invasion and metastasis of oral cancer cells. Methods With RT-PCR assay , Western blot，the expression of MMPs on mRNA and protein were detected respectively before and after stimulation of TNF-α. Transwell invasion assay was applied to detect the change of invasion and metastasis ability of oral cancer cells before and after the experiment. Results mRNA level of MMP-2, MMP-9, MMP-14 on oral cancer cells was significantly higher 24 h, 48 h and 72 h after stimulation of TNF-α respectively. The protein expression of MMP-2, MMP-9, MMP-14 was in accordance with mRNA level after 48 h. And the ability of invasion and metastasis has obviously enhanced after the stimulation of TNF-α. Conclusions TNF-α may promote the invasion and metastasis of oral cancer cells by up-regulating the expression of MMPs.

Objective To study the effect of D-Tryptophan, D-Leucine, D-tyrosine, and D-Methionine on the formation of biofilm Porphyromonas gingivalis (P. gingivalis) W83. Method: P. gingivalis W83 were cultured in Trypticase soy broth (TSB) supplemented with vitamin K (1μg/ml) and hemin (5 μg/ml) to mid-log phase, and then were diluted 1:100 in 96 well flat-bottom poltstyrene plates and add D-Tryptophan (5mmol/L), D-Leucine (8.5 mmol/L), D-tyrosine (3μmol/L), and D-Methionine (2mmol/L). The biofilms were stained with 25μl of 1% crystal violet, washed with ddH2O and dissolved in ethanol. The absorbance was measured with xMark microplate spectrophotometer at 570nm. Result: The absorbance of P. gingivalis W83 in TSB, D-Tryptophan, D-Leucine, D-tyrosine, and D-Methionine were 3.70 ± 0.06, 2.74 ± 0.18, 0.71 ± 0.04, 3.42 ± 0.02, and 3.65 ± 0.01 respectively. There was significance difference between TSB and D-Leucine groups (p<0.01). Conclusion D-Leucine (8.5 mmol/L) can reduce the biofilm formation of P. gingivalis W83.

objective The aim of this study was to estimate the amount of fluoride released from three different bonding adhesives by ion selective electrode method.Methods Thirty samples 10mm in diameter and 1 mm in height were divided into 3 groups with 10 in each group. The samples were separately filled into a plastic annular plate,and probes were used to remove overflowing resin at the edge of the mold. After the bonding adhersives were cured, they were stored in 10ml deionized water. The fluoride analysis were carried out using the ion specific electrode for first seven days and there after at every week end for four subsequent weeks. Result There was significant difference among three materials in the amount of released fluoride. Glass inomer cement (TP Orthodontics, USA) released the highest amount of fluoride. There was no significant difference between complex curing glass inomer cement (3M, USA) and Rely-a-bond (Reliance Orthodontic, USA) in the amount of released fluoride. Conclusion All the three bonding adhesives (traditional glass inomer cement, resin reinforced glass inomer cement, and fluoride releasable resin cement ) prove to be effective long term fluoride releasing materials.

Abstract： Objectives To assess the usefulness and reliability of the gingival crevicular blood for estimating the glucose level during routine periodontal examination. Methods Thirty patients with chronic periodontitis were selected (21 men and 17 women). Blood sam?ples were collected from gingival crevicular blood and fingerstick capillary blood respectively and detected with blood glucose meter. Results Measurements from gingival crevicular blood samples ranged from 4.8 to 16.7mmol/L with a mean of 7.77±3.43mmol/L and glucose measurements obtained from fingerstick capillary blood ranged from5.0 to 17.0mmol/L with a mean of 7.94±3.67mmol/L. Data were analyzed using a Pearson’s corre?lation coefficient and paired t-test. Paired t-test (P=0.114) showed no significant difference while a r-value of 0.990 showed very strong correlation between gingival crevicular blood and fingerstick capillary blood, which was statis?tically significant (P<0.001). Conclusion The data from this study has shown that gingival crevicular blood may serve as a potential source of screening for diabetes during routine peri?odontal examination in populations with an unknown history of diabetes mellitus.

Objective　To compare the influence of implants with different diameters and lengths on the stress distribution of implant - bone interface. Methods　According to the different lengths and diameters of the implant,, fully three-dimensional finite element model was established. The 3 I implant system used as reference, 3D entity model including the implant, corresponding abutment and dental crowns was drawn with Solidworks 3D cartography software. The group for size analysis consisted of 16 implant model with the cross combination of the different lengths which were set to 8 mm, 10 mm, 12 mm, 14 mm and the different diameters set to 3.5 mm, 4.0 mm, 3.5 mm, 5.0 mm. Take vertical and oblique loading on each model, and compare Von Mises stress distribution and the trend of stress changes of each model with Ansys Workbench13.0. Results Under each loading, the Von Mises stress of implant-bone interface in all models concentrated in the cortical bone around the neck of implant and cancellous bone area of the root tip. With the increase of implant length, stress concentration in the cancellous bone area of the root tip slowly declined while with the increase of the diameter, the stress concentration decreased significantly. Conclusion　Both diameter and length have an influence on the stress concentration of implant - bone interface. The longer the diameter and the length, the smaller the stress concentration. Compared with length, diameter has a more significant influence.

[Abstract] Objective: To evaluate the hemostitic effect and biocompatibity of oral soluble hemostatic guaze as well as its effect on the proliferation of human gingival fibroblasts. Method: Cell culture extracts of soluble hydroxyethyl haemostatic gauze and other hemostatic materials were prepared. Methyl thiazolyl tetrazolium(MTT) assay was used to determine the effect of the materials on the growth of human gingival fibroblast cells. The solubility of the soluble hemostatic gauze in aritificial saliva was observed and the blood clotting index (BCI) in vitro of soluble hemostatic guaze and other hemostatic materials were compared. Result: The solution rate of soluble hemostatic gauze in aritificial saliva was higher. The BCI of soluble hemostatic gauze was significantly lower than that of medical gauze and gelatin sponge and the difference was statistically significant, yet there was no significant difference in cell proliferation rate observed between soluble hemostatic gauze and gelatin sponge. Cytotoxical grade was 0 to 1.Coclusion: The oral soluble hemostatic gauze has showed good solubility and hemostatic effect, and it had no significant cyctoxicity to HGFC.

Objective　Preparation of modified bone morphogenetic protein-2 polylactic acid sustained-release nanosphere (rhBMP-2-mPEG-PLA-Ns) for the purpose of bone formation, and to study their physical and chemical properties and release studies in vitro. Methods　rhBMP-2-mPEG-PLA-Ns was prepared by emulsion The surface morphology of the nanosphere was observed by perspective electron microscope, laser particle size distribution of the nanospheres was tested by Malvern laser. Encapsulation efficiency and drug loading of the microspheres were measured by ELISA. Release delivery rate in vitro was tested by the dynamic dialysis drug Determination. Result　The nanospheres have smooth, rounded surfaces and uniform particle size. The particle size of the nanospheres was ranged between 45 ~ 50nm. Encapsulation efficiency and drug loading were respectively (78.2±1.81)% and [(2.24±0.24)×10-5]%. The release in vitro found no burst release, the release rate was 23.47% in 24 hours，and was 78.56% within 21 days. Conclusions: rhBMP-2-mPEG-PLA nanospheres had a good physical and chemical properties and sustained release effect, and had a good foundation for further applications.

Objective To investigate the effect of polishing on the surface roughness and abrasion resistance of two kinds of ceramics materials. Methods The surface roughness value and scanning electron microscopy（SEM）were used to analyze the influence of polishing on the surface roughness of two kinds of ceramics materials: Emax porcelain and Everest zirconium dioxide. The effects of polishing on wear property were also evaluated by wear test. Results The ceramic surface became much smoother after polishing（P<0.05）.The polished specimens caused significantly lower volume loss of specimens and opposite talcum ceramic than the unpolished ones（P<0.05）.Conclusions Surface polishing could decrease the surface roughness of the ceramics. The polishing procedures could also reduce the wear of the natural enamel and increase the abrasive resistance of ceramics.

［Abstract］ Objective To study the clinical efficacy of reduction and fixation of the traumatic embedded dislocation of young permanent anterior teeth. Methods 39 embedded dislocated young permanent teeth selected from 26 cases from August 2009 to June 2012 were set as the treatment group and they were treated according to the properties of different types. (1)When the embedded depth was ≤ 2mm,the teeth were reset to the original intercuspal position and fixed;(2)When the embedded depth was＞2mm , and there were multiple fractures in alveolar fossa and the loosening of teeth, the teeth were fixed in situ; 3)When the embedded depth was＞2mm ,and the teeth were locked in alveolar cavity and there was no loosening, the teeth were reset 1mm and then fixed.41 embedded dislocated young permanent teeth were fixed in situ and set as the control group. Results After 1 and half years of clinical observation, the retention rate of the treatment group was about 87.18% and the vital pulp rate was 43.59% while the rates in control group were respectively 58.54% and 24.39%. The retention rate and the vital pulp rate in treatment group were obviously higher than in control group. Conclusion Adopting different methods of reduction and fixation according to different embedded depths and the surrounding alveolar bone is a more effective way to treat the traumatic embedded dislocation of young permanent anterior teeth. It can more effectively keep the teeth and the vital pulp.

Objective To study the effects of the different concentrations of tea polyphenols and grapefruit-seed extract mixtures on water- insoluble glucan of Streptococcus mutans (S.mutans), and to further explore the cariostatic mechanism of S.mutans in order to provide much more profitable experimental proof for the clinical practice of the mixture. Methods The 4 mixtures(1/2、1/4、1/8、1/16 MIC) of TP and GSE sub-MIC were cultivated with S.mutans. The supernatant was collected and to measure the content of extracellular polysaccharide with anthrone method. Results The content of water insoluble glucan of S.mutans decreased gradually when the concentrations of TP and GSE mixtures increased. However, in terms of water soluble glucan content, compared with control group, only the experimental group with the highest concentration showed obvious difference (P<0.05). Conclusion The mixture of TP and GSE can effectively inhibit WIG of S.mutans, but it has no obvious inhibitory effect on water-soluble polysaccharide of S.mutans.

Objective To compare the postoperative sensitivity of deep caries treated with 3M light cured glass ionomer and DMG Ionosit-Baseliner. Methods A total of 84 posterior teeth with deep caries from 84 patients were randomly divided into two groups: 3M group and DMG group. 3M VitrebondTM light cured glass ionomer was used as liner material in Group 3M and Ionosit-Baseliner was used in Group DMG. After etching, both groups were filled with 3M FiltekTM Z350 nano composite resin. The sensitivity and the pain degree were evaluated and compared 1 day, 1 week, 1 month and 3 months after operation. Results There was no significant difference in the postoperative sensitivity and self-pain level between the two groups after 1 day, 1 week and 1 month （P>0.05）. Compared with group DMG, the incidence of sensitivity and self-pain level were lower in group 3M 3 months after operation（P<0.05）.Conclusions In posterior restorations, the light cured glass ionomer can reduce the incidence of postoperative sensitivity.

Objective The purpose of this study was to explore the effects of pure titanium discs treated with hydrogen peroxide and heat on attachment, proliferation and differentiation of MC3T3-E1 cells of mice. Methods Sandblasted, dual acid-etched titanium discs were set as control group, whereas sandblasted, acid-etched and hydrogen peroxide and heat treated titanium discs were as test group. Scanning electron microscope (SEM) and X-ray diffraction (XRD) were used for surface characterization. Pre-osteoblasts MC3T3-E1 were seeded on these discs in 2 groups, and then early cell attachment, cell proliferation and cell differentiation were evaluated. Results SEM analysis showed that the titanium discs in the 2 groups both had roughened surfaces with porous network structure. However, XRD examination indicated that anatase only covered on the surfaces in the test group. Early attachment of osteoblasts was much stimulated by the titanium discs in the test group (P<0.05). Besides cell proliferation on the surfaces of titanium discs was faster in the test group (P<0.05). Meanwhile, alkaline phosphatase activity and osteocalcin production on surfaces of titanium discs were dramatically elevated in the test group, whether in protein level or in transcriptional level. Conclusions Sandblasted, acid-etched and hydrogen peroxide and heat treated pure titanium implants are prone to integrate with surrounding bone tissue.

Objective To observe the efficacy and safety of total glucosides of paeony combined with intralesional triamcinolone acetonide injection for oral lichen planus. Methods 58 patients with clinically confirmed erosive and ulcerative OLP were randomly divided into two groups, treated with TGP+TA and TA separately, meanwhile the VAS and REU scoring system was utilized to compare the signs and symptoms. Results There were no statistical significance of effective rate between the treatment group and control group（χ2=0.112，P>0.01）at the first month, there were statistical significance of effective rate between the treatment group and control group（χ2=15.241，P<0.01）at the third month, and so did at the sixth month (χ2=34.621，P<0.01). Conclusion Total glucosides of paeony combined with intralesional triamcinolone acetonide injection can significantly enhance the effect safely in the treatment of OLP.

Objective　To study the relationship between impaction types and extraction time and accordingly make a new classification of mandibular third molars. Methods　There were 413 mandibular third molars included in the study. The impaction types were classified according to Pell-Gregory classifications (ramus and occlusal) and Winter classification. Ri、Oi、Wi were used to represet the index of immpaction respectively. Ci represents comprehensive impaction index of mandibular third molars. Ci=Ri+Oi+Wi. Extraction difficulty of mandibular third molars was measured by extraction time. ANOVA was used to compare the difference of extraction time between every two comprehensive impaction indexes of mandibular third molars. Classify mandibular third molars according to comprehensive impaction index and extraction time. Results　The extracion time became longer with greater comprehensive impaction index. There were significant differences in extraction time among mandibular third molars in some comprehensive impaction indexes. Mandibular third molars could be divided into six categories(Ⅰ～Ⅵ) according to comprehensive impaction index and extraction time. Conclusion　There was a close relationship between the extraction difficulty and impaction types of mandibular third molars. The new established classification of mandibular third molars can reflect their extraction difficulty better.