Methods: First, scanning electron microscopy (SEM) micrographs were analyzed to determine the porous structure of dentin. Subsequently, with photolithographic techniques, uniform polystyrene culture dishes were made with similar surfaces. On such dishes and smooth controls, primary PDLF or GF were seeded. On day 1, 4 10 and 14 of culture, samples were assayed for proliferation, alkaline phosphatase (ALP) activity, and collagen production. Finally, cell morphology was observed with SEM, and transmission electron microscopy (TEM).
Results: The number of tubuli was measured to be 180.000/mm2, with a 2.43 um diameter. Based on these parameters, culture dishes were designed. In the cell cultures, no differences in proliferation were observed. As expected, PDLF produced more ALP than GF. Noticeably, abundant collagen fibers were only formed on the textured surfaces. SEM assessment showed equal spreading of both cell types on smooth and textured surfaces. TEM showed that preferential deposition of extracellular matrix (ECM) material within the texture porosity had occurred.
Conclusion: Dentin surfaces could be reproduced in standard culture dishes. Microtextured surfaces had no negative effect on attachment, spreading and proliferation of the cells. However, surfaces could be used to enhance ECM deposition. Final efficacy of the surfaces has to be proven in animal experiments.