Large-size mandible graft has huge needs in clinic caused by infection,tumor,congenital deformity,bone trauma and so on.However,the reconstruction of large-size mandible defect is challenged due to its complex anatomi...Large-size mandible graft has huge needs in clinic caused by infection,tumor,congenital deformity,bone trauma and so on.However,the reconstruction of large-size mandible defect is challenged due to its complex anatomical structure and large-range bone injury.The design and fabrication of porous implants with large segments and specific shapes matching the native mandible remain a considerable challenge.Herein,the 6%Mg-doped calcium silicate(CSi-Mg6)andβ-andα-tricalcium phosphate(β-TCP,α-TCP)bioceramics were fabricated by digital light processing as the porous scaffolds of over 50%in porosity,while the titanium mesh was fabricated by selective laser melting.The mechanical tests showed that the initial flexible/compressive resistance of CSi-Mg6 scaffolds was markedly higher than that ofβ-TCP andα-TCP scaffolds.Cell experiments showed that these materials all had good biocompatibility,while CSi-Mg6 significantly promoted cell proliferation.In the rabbit critically sized mandible bone defects(∼13 mm in length)filled with porous bioceramic scaffolds,the titanium meshes and titanium nails were acted as fixation and load bearing.The results showed that the defects were kept during the observation period in the blank(control)group;in contrast,the osteogenic capability was significantly enhanced in the CSi-Mg6 andα-TCP groups in comparison with theβ-TCP group,and these two groups not only had significantly increased new bone formation but also had thicker trabecular and smaller trabecular spacing.Besides,the CSi-Mg6 andα-TCP groups showed appreciable material biodegradation in the later stage(from 8 to 12 weeks)in comparison with theβ-TCP scaffolds while the CSi-Mg6 group showed much outstanding mechanical capacity in vivo in the early stage compared to theβ-TCP andα-TCP groups.Totally,these findings suggest that the combination of customized strength-strong bioactive CSi-Mg6 scaffolds together with titanium meshes is a promising way for repairing the large-size load-bearing mandible defects.展开更多
基金supported by the National Key Research and Development Program of China(2017YFE0117700 and 2018YFA0703000)the Science and Technology Department of Zhejiang Province Foundation(LGF20H140008 and GF22E038891)National Natural Science Foundation of China(81871775 and 81902225).
文摘Large-size mandible graft has huge needs in clinic caused by infection,tumor,congenital deformity,bone trauma and so on.However,the reconstruction of large-size mandible defect is challenged due to its complex anatomical structure and large-range bone injury.The design and fabrication of porous implants with large segments and specific shapes matching the native mandible remain a considerable challenge.Herein,the 6%Mg-doped calcium silicate(CSi-Mg6)andβ-andα-tricalcium phosphate(β-TCP,α-TCP)bioceramics were fabricated by digital light processing as the porous scaffolds of over 50%in porosity,while the titanium mesh was fabricated by selective laser melting.The mechanical tests showed that the initial flexible/compressive resistance of CSi-Mg6 scaffolds was markedly higher than that ofβ-TCP andα-TCP scaffolds.Cell experiments showed that these materials all had good biocompatibility,while CSi-Mg6 significantly promoted cell proliferation.In the rabbit critically sized mandible bone defects(∼13 mm in length)filled with porous bioceramic scaffolds,the titanium meshes and titanium nails were acted as fixation and load bearing.The results showed that the defects were kept during the observation period in the blank(control)group;in contrast,the osteogenic capability was significantly enhanced in the CSi-Mg6 andα-TCP groups in comparison with theβ-TCP group,and these two groups not only had significantly increased new bone formation but also had thicker trabecular and smaller trabecular spacing.Besides,the CSi-Mg6 andα-TCP groups showed appreciable material biodegradation in the later stage(from 8 to 12 weeks)in comparison with theβ-TCP scaffolds while the CSi-Mg6 group showed much outstanding mechanical capacity in vivo in the early stage compared to theβ-TCP andα-TCP groups.Totally,these findings suggest that the combination of customized strength-strong bioactive CSi-Mg6 scaffolds together with titanium meshes is a promising way for repairing the large-size load-bearing mandible defects.