Statement of problem. The wear of human enamel and of the restorative material is often a critical concern when selecting a restorative material for any given clinical restorative treatment. Purpose. This in vitro wear investigation evaluated three ceramic restorative materials and one type III gold (the control) opposing enamel. Material and Methods. The area of enamel lost at specified time intervals, the stylus area lost, and the combined stylus and enamel vertical height lost were evaluated. Results. Enamel wear opposing one type III gold was statistically similar to that of Dicor MGC, which was lower than that of Vita Mark II and IPS Empress, which were also statistically similar in value. Conclusions. The total vertical height lost from the type III gold specimens and opposing enamel was statistically lower than that of Dicor MGC and IPS Empress (α < 0.05). (J Prosthet Dent 1997;77:523-30.). © 1997 Editorial Council of The Journal of Prosthetic Dentistry.