Objective To compare the effect of guiding boneregeneration between l-ethyl-3(3-diaminopropyol)-carbodiimide(EDAC)crosslinked acellular bovine pericardium (ABP) and medical collagen membrane (CM). Methods Defects of 7 mm×7 mm×5 mm were created in both mandibles of 24 rabbits, which weighted 2.6～3.5 kg. One side defect was covered with EDAC-crosslinked ABP(EDAC-crosslinked ABP group), the other side defect with medical CM as control(CM group). The ability of bone defect repair and change ofboth membrane materials were evaluated by gross observation, histological study and computer graphic analysis in the 4th, 8th, 16th and 24th weeks after operation. Results The surface of bone defects was even, consistent with adjacent normal bonein EDACcrosslinked ABP group, while that of bone defects was of no evenness in CM group in the 16th and the 24th weeks. The histological observation showed that bone trabecula formed in the EDAC-crosslinked ABP group and fibrous connective tissue was seen in CM group in the 16th and the 24th weeks. There were no significant differences in new bone percentage of bone defects between 2 groups inthe 4th and the 8th weeks(P＞0.05). In the 16th week new bone percentage of bone defects was 81.99%±3.92% in EDAC-crosslinked ABP group and 76.35%±4.29% in CM group, showing significant difference (Plt;0.05). The average percentage of absorption in EDAC-crosslinked ABP group was 16.57%, 27.94%, 65.61% and85.72% in the 4th, 8th, 16th and 24th weeks respectively, while that in CM group was more than 50% in the 4th week and completely degraded at the end of 8 weeks. Conclusion EDAC-crosslinked ABP has a better effect on guiding bone regeneration than CM in the repair of bone defects.
Objective To choose the best procedure on preparation of acellularbovine pericardium (ABP) guided bone regeneration (GBR) material. Methods The BP was decellularized with 0.25% Trypsin+0.5% Triton X-100. The acellular bovine pericardiums (ABPs) were treated with phosphatebuffered saline(PBS) (group A), 95% glycerol (group B), EDAC (group C), and EDAC and 95% glycerol (group D) respectively. The treated ABPs were implanted subcutaneously in the back of SD rats respectively at random and no material was implanted as control. Seven rats were sacrificed at 2 weeks, twelve at 4 weeks, twelve at 8 weeks, seven at 16 weeks. Local reaction was studied grossly. The amount of antigen presenting cell (APC) and the percentage of ABP degeneration were reckoned by images analysis system. Results The ABPs were replaced by fibroblasts completely in group A at 8 weeks， in group C at 16 weeks, but only less than 50% till 16 weeks in groups B and D. In all groups, the depth of surrounding fibres attenuated timedependingly. The APC amount of the groups B and D was higher than that of the control group, and the ABP of the groups B and D degraded partly at 16 weeks. Conclusion The ABP treated with EDAC can be replaced by the surrounding tissues and has good biocompatibility.
ObjectiveTo investigate the effects of modification of acellular bovine pericardium with 1-ethyl-3-(3-dinethylami-nopropyl) carbodimide (EDC)/N-hydroxysuccininide (NHS) or genipin and find out the best crosslinking reagent. MethodsThe cellular components of the bovine pericardiums were removed. The effects of decellularization were tested by HE staining. The acellular bovine pericardiums were crosslinked with EDC/NHS (EDC/NHS group) or genipin (genipin group). The properties of the crosslinked acellular matrix were evaluated by scanning electron microscope (SEM), matrix thickness, crosslinking index, mechanical property, denaturation temperature, enzymatic degradation, and cytotoxicity test before and after the crosslinking. Acellular bovine pericardium (ABP group) or normal bovine pericardium (control group) were harvested as controls. ResultsSEM showed that collagen fibers were reticulated in bovine pericardial tissues after crosslinked by EDC/NHS or genipin, and relative aperture of the collagen fiber was from 10 to 20 μm. The thickness and denaturation temperature of the scaffolds were increased significantly after crosslinking with EDC/NHS or genipin (P<0.05), while there was no significant difference between EDC/NHS group and genipin group (P>0.05). The difference had no statistical significance in crosslinking index between EDC/NHS group and genipin group (t=0.205, P=0.218). The degradation rate in EDC/NHS group and genipin group was significantly lower than that in ABP group and control group (P<0.05). Elastic modulus and fracture stress in EDC/NHS group and genipin group were significantly lower than those in ABP group (P<0.05), but there was no significant difference among EDC/NHS group, genipin group, and control group (P>0.05). The break elongation in EDC/NHS group and genipin group were significantly increased than those in ABP group and control group (P<0.05). The difference had no statistical significance in stability and mechanical properties between EDC/NHS group and genipin group (P>0.05). Cytotoxicity of genipin crosslinked tissue (grade 1) were much lower than that of EDC/NHS (grade 2) at 5 days. ConclusionAcellular bovine pericardium crosslinked with genipin has better biocompatibility than EDC/NHS.