Tissue reactions to polyethylene implants with different surface topography

This study investigates the importance of implant surface topography on soft tissue response. The tissue response in the rat abdominal wall to discs of low density polyethylene with smooth to coarse surfaces was evaluated after one, six or 12 weeks. Capsule thickness and immunohistochemical quantification of monocytes-macrophages were used as measures. The macrophage specific antibody ED1 was used for identification of newly recruited macrophages and the ED2 antibody for the mature tissue macrophages. The smoother surfaces gave a thicker capsule than the rougher surfaces, and at one week also larger total numbers of cells and ED1 positive macrophages at interface. The capsule thickness increased over time for the smooth and intermediate surface topographies. In contrast, the cell numbers generally decreased over time. In conclusion, a coarse surface elicited lesser tissue reaction compared with a smooth surface.