Formation Of TiO₂ Nanotube Arrays On Porous Zirconium Scaffolds And Their Effects On Osteogenic Differentiation Of Human Dental Pulp Stem Cells

Objective:The TiO₂ nanotube array currently used in bone tissue engineering is basically formed on the surface of Ti plate by anodic oxidation.Therefore,its application is limited by the inherent properties of Ti metal and cannot meet the diversified requirements of bone repair and the development of bone tissue engineering composite materials'trend.This experimental plan is to find a technology that can break through the limitations of Ti plates and form TiO₂ nanotube arrays on the surface of dissimilar materials,compound them on the surface of the ZrO₂ three-dimensional porous scaffold,and explore the effect on the early Osteogenesis-related behaviors of h DPSCs.Methods:Replication technique made ZrO₂ porous scaffolds were coated with 5,15,30%TiO₂ slurries respectively.After heated for 2h at 500?,samples were respectively immersed in 10mol/L Na OH for 12,24,36h at 110?.Scaffolds'compressive strength and porosity were characterized,and SEM scanned their surface,while EDS examined element types and their proportions.Screened optimal group was examined crystal structures by LRS and cultured with h DPSCs.The control group(none nanotube arrays)and the experiment group(equipped with nanotube arrays)were seeded with h DPSCs.SEM and phalloidin visualized cells'adhesion.Their proliferation was determined by CCK-8 and osteogenic differentiation was determined by ALP and EDS analysis.Results:TiO₂ nanotube arrays were formed on the surface of the samples treated with15%TiO₂ slurry and Na OH for 24 hours.15,30%TiO₂ coat treated with Na OH for24h could increase the compressive strength of the scaffold,and the 15%TiO₂ coat attained the most regular tube arrangement.Confirmed as rutile,TiO₂ nanotube arrays were observed on scaffolds(15%and Na OH 24h)of which porosity is 80%and compressive strength is 1.89MPa.Cells on the experiment group's sample had more pseudopodia and extended better after seeded 6h compared with the control group's.Experiment group had more bone deposition related elements on surface and more ALP significantly higher than control group(P<0.05),while results of CCK-8 showed no statistical difference(P>0.05).Conclusion:TiO₂ nanotube arrays were successfully formed on ZrO₂ porous scaffold.The Ti O2 nanotube arrays mildly strengthened scaffolds and facilitated adhesion and osteogenic differentiation of human dental pulp stem cells in vitro,but have no influence on proliferation.