Effect of mussel adhesive protein coating on osteogenesis in vitro and osteointegration in vivo to alkali-treated titanium with nanonetwork structures

Derong Yin,1 Satoshi Komasa,1 Shigeki Yoshimine,1 Tohru Sekino,2 Joji Okazaki11Department of Removable Prosthodontics and Occlusion, Osaka Dental University, Hirakata, Osaka, Japan; 2Advanced Hard Materials, The Institute of Scientific and Industrial Research, Osaka University, Suita, Osaka, JapanPurpose: On the basis of reasonable superposition of various surface treatment methods, alkali-treated titanium with nanonetwork structures (TNS) was coated with mussel adhesive protein (MAP) and named TNS-MAP. The aims were to optimize the biological properties of TNS, endue it with new properties, and enhance its utility in clinical dental applications.Methods: TNS disks were coated with MAP and the product surface was characterized. Its osteogenic properties were determined by evaluating its effects on cell adhesion, cell proliferation, the expression of osteogenesis-related genes, and in vivo experiments.Results: The treated materials showed excellent hydrophilicity, good surface roughness, and advantages of both TNS and MAP. TNS-MAP significantly promoted initial cell attachment especially after 15 mins and 30 mins. At every time point, cell adhesion and proliferation, the detection rate of osteogenesis-related markers in the extracellular matrix, and the expression of osteogenesis-related genes were markedly superior on TNS-MAP than the control. The in vivo experiments revealed that TNS-MAP promoted new bone growth around the implants and the bone–implant interface.Conclusion: We verified through in vitro and in vivo experiments that we successfully created an effective TNS-MAP composite implant with excellent biocompatibility and advantages of both its TNS and MAP parent materials. Therefore, the new biocomposite implant material TNS-MAP may potentially serve in practical dentistry and orthopedics.Keywords: biocomposite, bone marrow mesenchymal stem cell, extracellular matrix, nanopore, polydopamine