Thermal and Chemical Modification of Titanium-Aluminum-Vanadium Implant Materials and Effect on Osteoblast (MG63) Cell Attachment

Titanium-aluminum-vanadium (Ti-6Al-4V) has been used for its biocompatibility and added mechanical strength. Information on the physical effect of surface treatment on alloyed titanium implant materials is lacking. Objective: To examine the Ti-6Al-4V oxide thickness and morphology modified through thermal and chemical treatments and effect on osteoblast cell attachment. Methods: Ti-6Al-4V discs were produced from stock, polished, and passivated. The discs were treated in various ways: heating to 600oC for 1 hour in oxygen or atmosphere (O2, atm) , 30% peroxide in acid and base, 9:1 (v/v) butanol treated, or combination of each with a final butanol step. Sample topography and roughness (RMS) was determined by Atomic Force Microscopy. Surface wettability was determined by contact angle analysis. Oxide chemistry was determined by ESCA. Bone-like osteoblasts (MG63) cell attachment was also examined. Results: The primary oxide was TiO2. The increase in % C-O for butanol treated discs suggests surface interaction between butanol and oxide. Heating caused an enrichment of Al and V within the surface oxide. AFM images showed control and butanol-treated surfaces were smooth and free of scratches. Heating in O2 or atm produced a thicker oxide with sharply defined crests and pits. Peroxide-treatment produced a thickened, but smoother oxide surface. Subsequent butanol treatment did not alter surface topography. Both oxide thickness measurements and RMS values were greatest for heating- and peroxide-treatment compared to control. Heat (either O2 or atm) and peroxide treatment resulted in a more hydrophilic surface compared to controls (P< 0.01). Post-treatment with butanol resulted in less hydrophilic surfaces than heating or peroxide treatment alone (P< 0.01). MG63 cell attachment was greatest for the peroxide/butanol, heat (atm), peroxide, and heat(atm)/butanol treated samples, respectively. Conclusion: This study provides insight into oxide thermal and chemical changes and its impact on cellular interaction. Supported by VA Merit Grant 2894-005