Attachment of Rabbit Bone Marrow Stromal Cells to Pure Titanium with Different Surface Characteristics*

Objective: Alterations in the commercially pure titanium (cpTi) surface may be undertaken to improve its biological properties. The aim of this study is to observe the early attachment of rabbit bone marrow stromal cells on surfaces of pure titanium with three different chemical etching. Methods: Commercially pure titanium surfaces were prepared by polishing through 600-grit sandpaper, sandblasting, then the pure titanium disks were etched respectively with HNO₃, hot H₂SO₄/H₂O₂ or hot H₂SO₄/HCl for 30 minutes. The treated disks were studied and analyzed with SEM and XPS. Rabbit bone marrow stromal cells were cultured for 30, 60, and 120 min on the disks. Cell adhesion was observed with florescence Microscopy and analyzed with MTT. Results: The disks etched with HNO₃ had a smooth surface, while the ones with hot H₂SO₄/H₂O₂ or hot H₂SO₄/HCl had rough surfaces. The main elements on three groups were titanium, oxygen and carbon. The level of cell adhesion increased with time on all surfaces. However, cell adhesion on disks treated with hot H₂SO₄/HCl was the highest at 60 and 120min. And the cell spreading was the worst on disks treated with H₂SO₄/H₂O₂. Conclusion: Combined surface analytical and cell/molecular biological techniques are powerful tools to broaden our understanding of biological events occurring at the implant-tissue interface. Data acquired from these in vitro techniques provide that bone cell adhesion on disks treated with hot H₂SO₄/HCl or HNO₃ was better than that on disks treated with H₂SO₄/H₂O₂. * Supported by National Natural Scientific Foundation of China, No. 30300392