Cell/Surface Interactions and Osseointegration of Ti-6AI-4V: Effects of Laser Microgrooves, Hydroxyapatite Nanorods, and Arginyl-Glycyl-Aspartic Acid (RGD) on Ti-6Al-4V

Abstract

This work presents the results of an experimental study of surface-modified Ti-6Al-4V designed to enhance implant integration with human fetal osteoblast (hFOB) cells. Three surface profiles—laser-grooved (LG), Hydroxyapatite (HA)-coated laser-grooved (LGH), and arginyl glycyl aspartic acid (RGD)-functionalized HA-coated laser-grooved (LGHR)—were developed and evaluated for their effects on hFOB cell attachment, spreading, proliferation, and ECM formation over a 28-day period. Cell-laden surfaces were analyzed using scanning electron and fluorescence microscopies, and cell proliferation was quantified using the Alamar Blue assay to provide additional insights. The surface characterization revealed that the LG substrate facilitated contact guidance, promoting directional cell alignment and attachment. The LGH substrate additionally created a bioactive interface by mimicking natural bone tissue, releasing calcium and phosphate ions that enhanced cell attachment and spreading. The LGHR substrate provided specific biological cues, further improving early cell attachment, accelerating proliferation, and promoting extracellular matrix (ECM) formation. Quantitative analysis confirmed that LGHR surfaces exhibited the highest cell density, areal coverage, and metabolic activity, particularly during the initial stages of culture, emphasizing the synergistic effects of HA and RGD coatings in accelerating osseointegration. This novel approach offers robust improvements in implant-tissue integration, accelerating wound healing and enhancing tissue compatibility, with promising implications for orthopedic and dental applications.