ATTACHMENT KINETICS AND DIFFERENTIATION OF OSTEOBLASTS ON DIFFERENT BIOMATERIALS

Primary bovine osteoblast cell cultures were used to study the respons e of osteoblasts ton three different biomaterials, ionomeric cement (I C), tri-calcium phosphate poly-L-lactic acid composite foil (TCP) and poly-L-lactate-polycitric acid composite foil (PLA). The cells which g rew on the materials produced all typical bone matrix proteins and wer e osteoblast-like as shown by immuno-staining. Analysis of the cell at tachment 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 surf ace. The kinetics of attachment appeared to be due to different surfac e wettabilities and could be expressed by a linear equation. Further i nvestigations showed an ion mediated attachment of osteoblasts on the surfaces. Quantitative analysis of non-collagenous protein matrix prod uction and DNA content per cell was carried out, showing the best resu lts for PLA, followed by IC and TCP, indicating that the material with the best primary attachment characteristics is not necessarily that o n which the cells differentiate the best. Scanning electron microscopy observations of primary outgrowth cultures showed close contact of os teoblasts on all surfaces. It was concluded that such techniques may b e developed as a means of batch testing bioactive biomaterials and inv estigating bone cell/biomaterial interactions.