Fig. 3.

EDAX analysis of mineral formed in MC3T3 osteoprogenitor cell cultures incubated for 1–4 weeks on untreated or pretreated Ti6Al4V disks that were uncoated or fibronectin-coated (FN). Cells were plated on disks, incubated with cell culture media containing 50 μg/ml ascorbic acid and 3mM β glycerophosphate for 1–4 weeks, fixed in 4% paraformaldehyde and images were captured by SEM. EDAX spectra were obtained for selected particles for each of the three experimental groups. Data represent means ±SE for a minimum of three independent cultures at each time point. No particles of any size containing calcium or phosphorus were detected on untreated or heat pretreated disks for the 1 week time point. ^a,b Significantly greater compared to the same experimental condition measured at 1 week (P <0.05 or less) or 1 and 2 weeks (P <0.05 or less), respectively, based on analysis of variance. FN, fibronectin; HEAT, heat pretreatment; RFGD, radiofrequency plasma glow discharge pretreatment.