Phosphate-based Anodic Oxidation Enhances the Surface Bioactivity and Osteogenic Responses of Commercially Pure Titanium

Abstract

This study evaluated the bioactivity of commercially pure titanium surfaces modified by anodic oxidation in phosphoric acid. Anodic oxidation produced a characteristic oxide layer, changed the surface morphology, reduced carbon contamination, and increased phosphorus and nitrogen incorporation. Rat bone marrow cell experiments demonstrated enhanced cell adhesion, alkaline phosphatase activity, calcium deposition, and osteogenesis-related gene expression, including Runx2, ALP, BMP-2, and Bglap, on the anodized titanium surface. These results suggest that phosphate-based anodic oxidation is an effective surface modification technique for improving titanium bioactivity and may contribute to early osseointegration in dental implant applications.