The cellular response to well‐characterized Ca‐P and Ti surfaces was analyzed. This study indicated that the ion‐beam sputtering process could produce a hydroxyapatite‐type coating. However, structural alterations such as the incorporation of CO3 and the loss of the OH groups were observed. The Ti surfaces were shown to be predominantly amorphous TiO2. The in vitro cell culture study showed no significant differences in cell number for the Ti and Ca‐P surfaces throughout the 12‐day study. Furthermore, the initial percentage of protein within the cell layers was significantly lower for cells on Ca‐P surfaces compared with the cell layer on Ti surfaces. However, after 3 h incubation, no significant difference in the percentage of protein was observed for the Ti and Ca‐P surfaces. © 1995 John Wiley & Sons, Inc. Copyright © 1995 John Wiley & Sons, Inc.