Preparation Of Novel Ceramic Scaffolds With Dual-pores And Its Biological Properties

Bene gnaft ned bine iranspirtation was a signifieant sibject in the field of the binetissive enginering Corregondingle biceennic sofiolds were gralually seplied to repsir of reconsined the bone defees.in addidon to goad blocompalibiliry an idal scaflold should have reasonable thee-dimesiseal(3D)strikture so that sor fisues can be implamled icto it fress casing mallsal has been frequemly used to pertsrs su(?)(?)awing to the(?)low high pomsity and comtreltle pare(?)however,the(?)(?)in the scaffold easilly famed during jthe freece coslng were not good the slption of the cells.compared with the aligred elanele sprical pores coule peovide the culls wuth more space for ins dupliction unforlusillely the spherkal pores were pocrly inler-connled,this limiting the scuth and the(?)of the cellsIn ceder to corome the(?)(?)we report a new structure of cemie sollolde we use peroide bydrogen and dsionised waler h2o2h2o soltion,(?)woter(TBA/H2O)as sojwer to prepare cemle shury,repechely dual-pores wecc fabricaced by the frease cosling the inflae of the wolome comtemt of the oenside in mised solwent,the solle eortint frazing and the speial deciric field adjuse(?)on the(?)propties of the ce(?)invesigned the morology and biolgical proprins of the coramic scffold were invesligUsing pomxide hydsogen and delonized(?)H2O-O2 H20 solution as the pore teming(?)the Hydroxyapatiole parous(?)cominng both the lamellar mocosperas and spherical(?)by the frecae(?)it can be seam tham using H2O as pore-fonming ayenr,anly bumellar pares are bomed in the GA sealold when j wol%5 vol%5(?)H2O2both bimellar and spheneal pores are aleared homer when the comcentike of H2O2reaches 9vol anly spharikal pass are fomed in the scaffald the pass struslire of the sfldid infle(?)the scafold peperred ty5 vol.H2o2 solution(?)(?)open porasity due no(?)pones are formed aleng the inter-euremelinl larrellar poret the seldold by 9(?)H2O2 has the hished lodel ponsity with the redaction of slurry con(?)tion the ponelty of sffulds grodunlhy(?)with the increasing of cooling velocity,the pore size gradually becomes smaller.When the electric field intensity was increased from 0 to 90 kV/m,the average diameter of lamellar and spherical pores in HA scaffold was increased from 460 ?m to 810 ?m,and from 320 ?m to 420 ?m,respectively.Vitro cellular assay indicates that HA porous scaffolds support the structure of spherical macrospores and lamellar macrospores with larger size were more conducive to cell growth,cell surface structure clear,spreading in good shape.The values of compressive strength of scaffold meet the requirement of bone tissue engineering.Using crystallized TBA/H2O(tert.-butyl alcohol/distilled water)solution as template,two kinds of Al2O3 porous bioceramic scaffolds with the lamellar and circular macrospores were fabricated by the freeze casting.The morphology of scaffold was examined by SEM and the biologic performance was tested also.The influences of the mass fraction of the TBA and the freezing temperature on the structure and properties of the Al2O3 scaffold were investigated systematically.The results show that the scaffold structure prepared from aqueous slurry is lamellar pores.The lamellar spacing decreases with increasing the content of TBA.The the morphology of pass is double-pores type,including lamellar and the circular pore,when the TBA content is 90 wt.%.The scaffold structure prepared from pure TBA is circular pores.The scaffold with dual-pores type owes the highest open porosity and total porosity,which are 78.5%and 81.8%,respectively.The pore is decreased with the freezing temperature lowered.Vitro cellular assay indicate that the scaffold with the lamellar macrospores and the circular macrospores was conductive to the cell growth,the cell absorption rate gradually increases with the pore size increased.Cell surface structure clear,spreading in good shape.Be based on the principle of human bone biomechanical,we analyzed the static stress of the model of the alumina scaffold.According to the distinct arrangement of the pores,pore size,and porosity and other parameters of the scaffold,we construct the model of lamellar pore scaffold and square pore scaffold,and four types of the dual-pores scaffolds(72 totals).Then,we selected limiting analysis of the model under the condition of the limit load.By contrasting of the compression of the model with single pore and dual pores.The results showed that:Based on the principle of the maximum porosity and meeting the requirement of the mechanical strength,The optimal scaffolds were obtained when the scaffolds with the pore size of 400?m,70%porosity;and the square pore and the lamellar pore as ratio of 1:1,crossing arrangement.