Use of Ti-coated replicas to investigate the effects on fibroblast shape of surfaces with varying roughness and constant chemical composition.

Abstract

A two-stage replica technique with a subsequent titanium (Ti)-coating treatment was used to faithfully replicate topographies of polished, acid-etched, machined-like, finely blasted, coarsely blasted, coarsely blasted and acid-etched, and Ti plasma-sprayed Ti surfaces. The replicas were used to study the influence of different rough surface topographies on the response of human fibroblasts in vitro under conditions of constant surface chemistry for all surfaces. The surface topographies of the replicas were characterized using non-contact laser profilometry, scanning electron microscopy (SEM), and stereo-SEM, whereas surface chemistry was examined using X-ray photoelectron spectroscopy. Fibroblasts were trypsinized and plated onto the Ti-coated epoxy-resin replica surfaces for 24 h and observed with SEM. Fluorescein-5-thiosemicarbazide was used to stain the cell components including cell membrane, and the stained cells were optically sectioned using epifluorescent microscopy. The optical sections were computationally reconstructed to obtain three-dimensional images and cell volume and cell thickness determined. The different surface topographies were found to alter cell thickness and cell morphology. However, cell volume as computed from three-dimensional reconstructions was not affected by surface features. The results suggest that cells distort themselves to accommodate to rough surfaces but their volume is not significantly altered.