The effect of poly-L-lactic acid with parallel surface micro groove on osteoblast-like cells in vitro

In this study we evaluated the behavior of rat bone marrow (RBM) cells on m icrogrooved poly-L-lactic acid (PLA) and polystyrene (PS) surfaces. The app lied groove depth was 0.5, 1.0 or 1.5 mu m, with a groove and ridge width o f 1, 2, 5 or 10 mu m. Scanning electron microscopical examination showed th at a collagen-rich mineralized layer of extracellular matrix (ECM) was depo sited. Alignment of the cells and matrix to the surface grooves was observe d as described before. Quantitative evaluation, using a tetracycline labeli ng assay, revealed that more mineralized ECM was formed on the PLA than on the PS. Further, PLA surfaces with a groove depth of 1.0 mu m and groove wi dths of 1 and 2 mu m induced most mineralized ECM. finally, alkaline phosph atase activity was also higher on most microgrooved PLA surfaces, compared with the other materials. On the basis of these observations, we concluded that microtextured surfaces are able to influence the differentiation of os teoblast-like cells and the deposition of mineralized matrix. Probably, thi s phenomenon can be used to increase the bone regeneration around oral impl ants. (C) 1999 Elsevier Science Ltd. All rights reserved.