Effect of laser-processed wavy microgrooves on the behavior of MC3T3-E1 osteoblasts

This study aims to investigate the effect of laser-processed wavy microgroove structures on the behavior of osteoblasts, particularly focusing on the improvement of osteointegration in titanium alloy implants. Titanium alloys are often used to fabricate bone fixation systems due to their excellent mechanical properties and biocompatibility. However, the bioinert surface properties of these materials often limit cell adhesion and bone tissue integration, which can lead to implant failure. In this work, we prepared wavy microgroove structures with different curvatures (150 μm, 200 μm, 300 μm, 400 μm, and 500 μm) on titanium alloys using picosecond lasers to enhance the biological activity of implanted materials. As a result, scanning electron microscopy (SEM) confirmed the morphology of these structures, while X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray spectroscopy (EDS) revealed that their chemical composition remained unchanged compared to flat surfaces. The series in vitro cell assays indicated superior adhesion and proliferation of MC3T3-E1 cells on microgrooves with a 300 μm curvature radius. RNA sequencing analysis showed the activation of osteogenesis-related pathways, including Notch and PI3K-Akt pathway, with significant upregulation of key genes such as Low-Density Lipoprotein Receptor-Related Protein 1(Lrp1), Platelet-derived growth factor receptor beta (Pdgfrβ), Receptor Tyrosine Kinase Like Orphan Receptor 2(Ror2), and Wnt family member 10B (Wnt10b), which are involved in cellular adhesion, differentiation, and bone formation. All these findings together demonstrated the potential of wavy microgroove structures in enhancing osseointegration and offers valuable insights for orthopedic implant design.