3D bioactive coatings with a new type of porous ridge/cavity structure

ABSTRACT In this study, biocompatibility of plasma-sprayed 3D CP Ti-coated wire implants has been evaluated. Plasma-sprayed 3D CP Ti coatings have a porous structure consisting of ridges and cavities whose height is equal to that of the thickness of the coating. The porosity of plasma-sprayed 3D CP Ti coatings was found to be higher in cavities and it made up 46%. To study the clinical success of these implants, post-mortem computed tomography (CT) of distal femurs of animals (mainly dogs) was carried out. In vivo studies failed to demonstrate an increase in the amount of new bone tissue around uncoated implants. The amount of new bone tissue around implants with additional ceramic coatings made up 60% after 8 weeks. The amount of new bone tissue around 3D CP Ti-coated implants was only 5% after 8 weeks; however, after 16 weeks, an intensive growth of bone tissue around implants was observed. The amount of new bone tissue around implants with an additional ceramic coating was insufficient after 16 weeks. Forty-eight weeks after implant placement, the distribution of bone tissue in 3D CP Ti, 3D CP Ti-HA- and 3D CP Ti-HA-CaP-coated implants was 74.5%, 89.2% and 92.5%, respectively. The amount of bone tissue around uncoated implants did not exceed 10%. 3D CP Ti-HA coatings demonstrated better osseointegration compared with 3D CP Ti coatings and were found to have higher shear strength (9.8±1.54 MPa) at early stages of osseointegration.