Attachment Kinetics and Differentiations of Osteoblasts on Different Biomaterials

Primary bovine osteoblast cell cultures were used to study the response of osteoblasts ton three different biomaterials, ionomeric cement (IC), tri-calcium phosphate poly-L-lactic acid composite foil (TCP) and polyL-lactate-polycitric acid composite foil (PLA). The cells which grew on the materials produced all typical bone matrix proteins and were osteoblast-Iike as shown by immuno-staining. Analysis of the cell attachment kinetics revealed significant differences within the first 7 hours between the various materials. The best rate of cell attachment was found on the IC surface , followed by the TCP and then the PLA surface. The kinetics of attach ment appeared to be due to different surface wettabilities and could be expressed by a linear equation. Further investigations showed an ion mediated attachment of osteoblasts on the surfaces. Quantitative analysis of non-collagenous protein matrix production and DNA content per cell was carried out, showing the best results for PLA, followed by IC and TCP, indicating that the material with the best primary attachment characteristics is not necessarily that on which the cells differentiate the best. Scanning electron microscopy observations of primary outgrowth cultures showed close contact of osteoblasts on all surfaces. It was concluded that such techniques may be developed as a means of batch testing bioactive biomaterials and investigating bone cell/biomaterial interactions.