1.Early revascularization of fat grafts conducted by basic fibroblast growth factor sustained-release system
Chinese Journal of Tissue Engineering Research 2013;(44):7745-7750
BACKGROUND:The resorption and unprediction of fat transplantation directly influence the clinical application. The technology of reducing graft resorption by using various cytokines to promote early revascularization of fat transplantation needs to be improved. But the effect is not stable, as the cytokines losing with the bleeding and exudation thus cannot long-term affect the vascular endothelial cells. OBJECTIVE:To investigate the effect of alkaline recombinant basic fibroblast growth factor-dextran formed sustained-release system on the early revascularization of fat grafts. METHODS:The recombinant basic fibroblast growth factor solution 2 mg/L and basic fibroblast growth factor-dextran sustained-release granules were prepared. The fat tissues were selected from the inguinal region of 12 Sprague-Dawley rats for fat transplantation. The left backs of the rats were treated with subcutaneously injection of fat pearl plus recombinant basic fibroblast growth factor solution (control group), and the right backs of rats were treated with subcutaneously injection of fat pearl plus basic fibroblast growth factor-dextran sustained-release granules (sustained-release system group). At 7 and 14 days after treatment, one rat in each group was sacrificed randomly, then ink perfusion microvascular imaging was used to observe the inside of the graft and the density of early formed coated vessels. At 90 days after transplantation, the rest rats were sacrificed, and the grafts were obtained to measure the volume. RESULTS AND CONCLUSION:At 7 and 14 days after transplantation, the number of vessels in the capsule and grafts of the sustained-release system group was higher than that in the control group (P<0.01). At 90 days after transplantation, the volume of grafts in the sustained-release system groups was bigger than that in the control group (P<0.05). The recombinant basic fibroblast growth factor-dextran delivery system could better promote the early revascularization of fat grafts. The experimental results suggest that recombinant basic fibroblast growth factor-dextran sustained-release system can help to reduce the absorption of fat grafts after surgery.
2.Relationship between tooth mobility and width of periodontal membrane
Sefei YANG ; Shenggen SHI ; Ming ZHANG ; Li Peng
Journal of Practical Stomatology 1995;0(04):-
Objective: To obtain the parameters related to the width of periodontal membrane from tooth mobility signal. Methods: Signals elicited from a tooth model of human maxillary central incisor, periodontal membrane made of silicone rubber and alveolar bone made of resin,were processed utilizing FX-1 tooth mobility measurement system. Results: R value of wave range,slope K and time parameter t2 in the tooth mobility signals were reduced with the increase of the width of periodontal membrane; time parameter t1 was increased with the increase of the width of periodotal membrane;R value and time parameter t2 were negatively correlated. Conclusion: R value and t2 may be the paticular indications reflecting the changing of width of periodontal membrane.
3.Primary observation on tooth mobility parameters in people with normal health teeth
Sefei YANG ; Shenggen SHI ; Yingliang SONG ; Li PENG
Journal of Practical Stomatology 2000;0(06):-
Objective: To obtaine the parameters of tooth mobil ity in people with normal health teeth . Methods:Tooth mob ility of 1 4, 1 4 in 12 subjects (7 males and 5 females, aged 21 to 23 years old) was measured by FX-1 tooth mobility measurement system 6 times a day for 5 days.The data were statisticaly analyzed. Results: The average tooth mobility parameters Q and R varied significantl y (P0.05).Conclusion: The tooth mo bility parameters of S,K,t1 and t2 can steadily reflect the changing of tooth mobility.
4.Technical operation of refractory investment for titanium crown and bridge
Sefei YANG ; Tianwen GUO ; Youxu WANG ; Zhihao JIN
Journal of Practical Stomatology 2000;0(06):-
Objective:To study the technical operation of self-developed investment (FUS-invest) for titanium crown and bridge. Methods:Orthogonal design was done. Four factors were taken into account, i.e. water/powder ratio, adhesive/hardener ratio, fine powder proportion in refractory and agitation time. And each factor was ranked into three levels. Slurry fluidity, initial setting time and setting time of every experiment group were studied. Grain size graduation of the best group was measured.Results:Fluidity, initial setting time and setting time were most greatly affected by water/powder ratio and secondly by fine powder proportion in refractory. When water/powder ratio was 7.5∶1 and the content of fine powder was 35%, slurry fluidity was better and initial setting time and setting time were appropriate. When the content of fine powder of AFS fineness number 300 was 31.31%, fineness number 100 was (40.09%), fineness number 70 was 18.05% and adhesive/hardness ratio was 200∶1, the perfect titanium castings could be fabricated. Conclution:The best rules of technical operation for perfect titanium castings are water/powder ratio (7.5)∶1, the content of fine powder 35% and adhesive/hardener ratio 200∶1.
5.Micro/nano hierarchical structure of titanium surface promotes MC3T3-E1 adhesion proliferation and drug loading potential evaluation
DING Tong ; WANG Jianhui ; XIAO Zhiyong ; WU Tengfei ; YANG Sefei
Journal of Prevention and Treatment for Stomatological Diseases 2023;31(8):543-551
Objective :
To investigate the effect of micro/nano hierarchical structures on the adhesion and proliferation of MC3T3-E1 cells, evaluate the drug delivery potential of titanium surfaces, and provide a reference for the modification of selected areas of titanium surfaces to enhance drug delivery and slow drug release.
Methods :
Pure titanium samples (10 mm in diameter and 2.5 mm in thickness) were randomly divided into a polished group (T), anodized group (TO), and micro/nano hierarchical structure group (FTO) according to the surface treatment of the titanium. The T group was polished, the TO group was treated with anodic oxidation technology, and the FTO group was treated by femtosecond laser etching combined with anodic oxidation technology. The three surface morphologies were observed by scanning electron microscopy (SEM), the wettability of the surface was measured by the contact angle, and the surface chemical composition was analyzed by X-ray energy dispersive spectroscopy (EDS). The depth of the FTO structure and the surface roughness were measured by confocal laser scanning microscopy (CLSM). MC3T3-E1 cell adhesion proliferation and differentiation on the surface of each group of samples was assessed by immunofluorescence staining, CCK-8, and semiquantitative analysis of Alizarin staining. A freeze-drying method was applied to load recombinant human bone morphogenetic protein-2 (rhBMP-2), and an enzyme-linked immunosorbent assay (ELISA) was used to assess the drug-loading potential of different surface structures.
Results:
SEM revealed that the surface of T group titanium plates showed uniform polishing marks in the same direction. The surface of the TO group was a nanoscale honeycomb-like titanium dioxide (TiO2) nanotube structure, and the FTO group formed a regular and ordered micro/nano layered structure. The contact angle of the FTO group was the smallest at 32° ± 1.7°. Its wettability was the best. The average depth of the first-level structure circular pores was 93.6 μm, and the roughness was 1.5-2 μm. The TO and FTO groups contained a high percentage of oxygen, suggesting TiO2 nanotube formation. The FTO group had the most significant surface cell proliferation (P<0.001) and the largest cell adhesion surface area (P<0.05). rhBMP-2 was slowly released for 14 d after loading in the FTO group and promoted extracellular matrix mineralization (P<0.001).
Conclusion
Titanium surface microprepared hierarchical structure has the effect of promoting MC3T3-E1 cell adhesion, proliferation, and osteogenic differentiation with drug loading potential, which is a new method of titanium surface treatment.