Surface properties and bacterial behavior of micro conical dimple textured Ti6Al4V surface through micro-milling

Abstract

Although several techniques have been utilized to alter micro/nanotopographies of implant surfaces to improve the osseointegration rate, it has been challenging to fabricate micro/nano directional textures of desired shape size and accuracy. In the present study, mechanical micro-milling is utilized to create orderly conical dimple textures on the Ti6Al4V surface. The surface characterization, 3D surface topography, form measurement, and surface roughness were performed using FESEM and 3D surface analyzer. The wetting behavior of surfaces assisted by measuring advancing, receding contact angle, and contact angle hysteresis with ultrapure water and diiodomethane. Further, the Surface free energy of implants using the Chibowski approach, Neumann's equation, and Owen &Wendt method were calculated. The surface properties were studied with the roughness factor. The bacterial cell behavior of textured surfaces was studied in detail. Bacterial response studies on various surfaces are highly essential to gain insightful information about the usage of implants. Results indicate that the formed textures are uniform, dimensionally accurate with no defects, and as per the design of the experiment. The area surface roughness, hydrophilicity rate, and surface free energy increased in all cases, and all the surface properties alter with a change in textures density. Further, the results show that bacteria respond to surface modifications through changes in cell surface membrane, cellular roughness, morphological changes, the appearance of cellular appendages, and EPS production. The present study provides insight details about the surface properties of the Ti6Al4V implant and will be helpful to facilitate cell attachment, adhesion, proliferation, and protein adsorption.