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Purpose: Electrospinning technology was used to construct PCL composite nanofiber scaffold material of BMP-2 sustained-release nanospheres, and the effect of this nanospheres on proliferation and differentiation of MC3T3-E1 cells was evaluated., Methods: Solvent removal method and electrostatic self-assembly technology were used to prepare BMP-2 loaded chitosan nanospheres, the morphology, particle size and composition, BMP-2 protein encapsulation efficiency, and in vitro sustained release were tested. Electrospinning technology was ued to prepare PCL composite scaffold material containing BMP-2 nanospheres, and its morphology, hydrophilicity,and sustained release of BMP-2 protein were examined. In vitro cytology experiment was conducted to observe the growth of cells in the material, and the formation of ALP, related genes, and mineralized nodules during the process of osteogenic differentiation of the material were detected. SPSS 21.0 software package was used for statistical analysis., Results: The nanospheres structure with stable structure was successfully prepared, with a high drug loading rate and sustained release of BMP-2. The PCL/BNPs scaffold material group had good hydrophilic properties and was conducive to cell proliferation and differentiation. The results of in vitro cell experiments showed that the cells spread well on the scaffold and the number of adhesions increased. ALP and related osteogenic genes COL1, OPN, RUNX2 increased, and the size and number of calcium nodules increased significantly., Conclusions: The polycaprolactone composite fiber scaffold material of BMP-2 sustained-release nanospheres can provide a new choice for the development of bone tissue engineering.

Purpose: To observe the effect of concentrated growth factor(CGF) on the biological properties of osteoblasts., Methods: MC3T3-E1 cells were cultured in CGF environment and a blank control group was established. The adhesion of osteoblasts to CGF surface was observed by scanning electron microscopy. Cell proliferation and alkaline phosphatase(ALP) activity were detected at 1, 4 and 7 d by Cell Counting Kit-8 (CCK-8) and Alkaline Phosphatase Assay Kit. The expression of mineralized nodules and osteogenesis-related gene Runx2 was observed by alizarin red staining. CGF extract was cultured for 24 h. Peptide staining was used to observe morphological changes in the cytoskeleton. SPSS 21.0 software package was used for statistical analysis., Results: CCK-8 showed cells incubated for 1, 4 and 7 d in the experimental group had a stronger proliferation ability compared with the control group, and the difference was statistically significant (P<0.05). ALP activity test showed that there was no significant difference between the experimental group and the control group (P>0.05) at 1 d; but after 4 days of culture, cell in the experimental group had an increased ALP activity compared with the control group, and the difference was statistically significant(P<0.05). The results of alizarin red staining showed that the number of calcified nodules in the CGF group increased and the area was larger. In the phalloidin staining and DAPI staining, the number of cells in the CGF group increased, the cell spreading surface increased, and the actin shape was clearer. CGF significantly promoted Runx2 mRNA expression(P<0.05)., Conclusions: High concentration of CGF can promote the proliferation and differentiation of MC3T3-E1 cells and the expression level of related osteogenic gene Runx2.

Purpose: To explore the effect of cinnamaldehyde(CA) on osteogenic function and BMP-2 expression of mice osteoblast., Methods: MC3T3-E1 sub-clone 14 cells were cultured in the presence of CA at 0(control group), 10, 20, 40, 80, 160， 320 μg/mL. The cell proliferation rate was measured by MTT assay 1, 3, 5 d after exposure. Activity of alkaline phosphatase (ALP) was detected at 3, 5, 7 d to observe the effect of 6 concentrations of CA on osteoblast function. The mRNA expression of BMP-2 was quantified by real-time PCR(RT-qPCR) 1, 3, 5 d after exposure to (10,20 μg/mL) CA. The data were analyzed by SPSS 17 software package., Results: MTT assay showed that compared with the control group, when 10, 20 μg/mL of CA acted on MC3T3, the absorbance value decreased slightly but the difference was not statistically significant (P>0.05), while ALP activity increased significantly. CA increased the mRNA expression of BMP-2 at the concentration of 10, 20 μg/mL (P<0.05),decreased the osteoblast proliferation, ALP activity and the mRNA expression of BMP-2 at the concentration of 40, 80, 160， 320 μg/mL (P<0.05); as the concentration of CA increased, the effects became more significant., Conclusions: CA(10, 20 μg/mL) exerted positive effects on osteogenic function, increased the ALP activity and the mRNA expression of BMP-2. It is suggested that the activity of osteoblast differentiation and osteogenic function may be related to the expression of BMP-2.

Purpose: To evaluate the effects of IL-1β on inflammatory factors synthesis of human gingival fibroblasts on different surfaces of titaniums in vitro., Methods: Human gingival fibroblasts were cultured on 3 different kinds of titaniums. The cells were stimulated with IL-1β, and the IL-6 and IL-8 production was detected by polymerase chain reaction (PCR) after 3, 6 and 24 h. The date was statistically analyzed with SPSS13.0 software package., Results: A significant increase of the expression of gingival fibroblasts to inflammatory factors (IL-6, IL-8) after IL-1β was noted; PCR results of the production of inflammatory factors in gingival fibroblasts with the intervention of IL-1β showed that the production of inflammatory factors (IL-6, IL-8) on titanium and titanium alloy were less than that on the titanium nitride., Conclusions: IL-1β can stimulate high expression of inflammatory factors; The production of IL-6 and IL-8 on titanium and titanium alloy are less, suggesting that implant made of titanium and titanium alloy can reduce the incidence of peri-implant inflammation, and improve the successful rate of implantation.

Purpose: To study the influence of post-cure treatment on the monomer conversion of 3 light-cured composite resins., Methods: Three kinds of light-cured composite resin: CHARISMA, DenFilTM Flow and nano-hydroxyapatite composite resin were double-side cured for 40 s. The materials without any secondary treatment were used as control group (group A). Group B were lighted in Translux CU light cure case for 5 min. Group C were subjected to post-cure heat treatment for 7.5 min at 140 degrees centigrade and Group D were post heated in 132 degrees centigrade and pressured 0.2 MPa for 6.5 min. Degree of conversion (DC) of all the samples was measured by Fourier transform infrared spectroscopy (FTIR). The data was analyzed using SPSS 13.0 software package., Results: The monomer conversion of light-cured composite resins improved at different degree after post-cure treatment, and group C was the most favorable group(P<0.05). Compared with the control group, group B and C had significant differences (P<0.05) except when the DenFilTM Flow and CHARISMA were lighted for 5 minutes (P>0.05). Among the experimental groups, there was no significant difference between each group of DenFilTM Flow groups, CHARISMA illumination and hot-pressing groups, and n-HA composite resin illumination compared with 140 degrees centigrade groups., Conclusions: Post-cure treatment can increase the monomer conversion of light-cured composite resin so as to improve material performance, particularly for the heat treatment for 7.5 min at 140 degrees centigrade.