Regulation of Cell Extension and Enhanced Osteoblast Proliferation on Titanium Surfaces Textured by Micro-Feed Cutting

Titanium (Ti) and its alloys are widely used in dental and orthopedic implants because of their biocompatibility and mechanical strength. Successful clinical outcomes depend on osseointegration, which is significantly influenced by the surface topography of the implant. Although micro-scale features are known to guide cell behavior, creating periodic and precise patterns on Ti is challenging due to its poor machinability. This study proposes a surface texturing approach using precision micro-feed cutting to create periodic micro-grooves. By increasing the tool feed rate, we fabricated various textured surfaces where the groove width expanded from sub-micron levels up to approximately 25 μm, with a corresponding increase in surface roughness. The influence of these topographies on the initial attachment and proliferation of osteoblasts was systematically evaluated. Experimental results indicated that the increased feed rates produced macro-grooves with a width of approximately 25 μm and a height of 6 μm, which significantly enhanced cell affinity and cell alignment along the groove direction. This dimension provides a suitable physiological space to accommodate the entire cell body, which typically measures 10-30 μm, while offering stable cell adhesion sites for microscopic attachment points. In contrast, lower feed rates resulted in narrower grooves below 10 μm that physically restricted the development of these adhesion sites, thereby limiting cell growth. These findings demonstrate that adjusting the mechanical cutting feed rate can effectively control the geometric environment for bone-forming cells. This technique offers a practical method for optimizing the surface structure of Ti implants to improve cell attachment and growth through mechanical parameter control.