Open-porous magnesium-based scaffolds withstand in vitro corrosion under cyclic loading:A mechanistic study  

作　　者：Roxane Bonithon Colin Lupton Marta Roldo Joseph Nicholas Dunlop Gordon William Blunn Frank Witte Gianluca Tozzi 

机构地区：[1]Zeiss Global Centre,School of Mechanical and Design Engineering,University of Portsmouth,Anglesea Road,PO13DJ,Portsmouth,United Kingdom [2]School of Pharmacy and Biomedical Sciences,University of Portsmouth,White Swan Road,PO12DT,Portsmouth,United Kingdom [3]School of the Environment,Geography&Geosciences,University of Portsmouth,Burnaby Road,PO13QL,Portsmouth,United Kingdom [4]Department of Prosthodontics,Geriatric Dentistry and Craniomandibular Disorders,Charite-Universitätsmedizin Berlin,Aßmannshauser Straße 4-6,14197,Berlin,Germany [5]Biotrics Bioimplants AG,Ullsteinstr.108,12109,Berlin,Germany

出　　处：《Bioactive Materials》2023年第1期406-417,共12页生物活性材料（英文）

摘　　要：The successful application of magnesium(Mg)alloys as biodegradable bone substitutes for critical-sized defects may be comprised by their high degradation rate resulting in a loss of mechanical integrity.This study investigates the degradation pattern of an open-porous fluoride-coated Mg-based scaffold immersed in circulating Hanks’Balanced Salt Solution(HBSS)with and without in situ cyclic compression(30 N/1 Hz).The changes in morphological and mechanical properties have been studied by combining in situ high-resolution X-ray computed tomography mechanics and digital volume correlation.Although in situ cyclic compression induced acceleration of the corrosion rate,probably due to local disruption of the coating layer where fatigue microcracks were formed,no critical failures in the overall scaffold were observed,indicating that the mechanical integrity of the Mg scaffolds was preserved.Structural changes,due to the accumulation of corrosion debris between the scaffold fibres,resulted in a significant increase(p<0.05)in the material volume fraction from 0.52±0.07 to 0.47±0.03 after 14 days of corrosion.However,despite an increase in fibre material loss,the accumulated corrosion products appear to have led to an increase in Young’s modulus after 14 days as well as lower third principal strain(εp3)accumulation(-91000±6361μεand-60093±2414μεafter 2 and 14 days,respectively).Therefore,this innovative Mg scaffold design and composition provide a bone replacement,capable of sustaining mechanical loads in situ during the postoperative phase allowing new bone formation to be initially supported as the scaffold resorbs.

关 键 词：Magnesium alloys Bone regeneration In vitro corrosion X-ray computed tomography(XCT) Digital volume correlation(DVC) 

分 类 号：R318.08[医药卫生—生物医学工程]