Standardized tests of bone implant surfaces with an osteoblast cell culture system. I. Orthopedic standard materials]

The effect of standard orthopaedic materials on proliferation and differentiation of osteoblasts was examined using a standardised cell culture system. Osteoblasts hFOB 1.19 were cultured on stainless steel (SS), a chromium-cobalt-molybdenum alloy (CrCoMb) and commercially pure titanium (cpTi) for 12 days. Cell culture polystyrene (PS) was used as a reference. Cell numbers and cell viability were used as parameters of proliferation. Cell differentiation was assessed using alkaline phosphatase activity, collagen I and osteocalcin production. The parameters of proliferation showed earlier maximum values on PS and cpTi, while proliferation was delayed on SS and CrCoMb. The highest values of differentiation were found on cpTi. The development of alkaline phosphatase activity showed two peaks reflecting apoptosis and redifferentiation. The cell culture system hFOB 1.19 is thus suitable for revealing differences in proliferation and differentiation of osteoblasts on standard orthopaedic materials. The results correlate with previous in vivo findings. Using this system, the dynamic effect of the material surface on the differentiation process of osteoblasts can be demonstrated.