Effect of multiple axial grooves on the marginal adaptation of full cast-gold crowns.

Twenty-seven crowns were fabricated on the standardized ivorine dies to determine the effect of multiple axial grooves. No grooves were placed on the control (group I). In groups II and III, respectively, two and four grooves were replaced. The mean value of the occlusal cement film thickness was used to appraise the vertical discrepancy (lack of seating) of the crown on the die. This value was obtained by averaging seven measurements of the occlusal cement film thickness taken at different areas. These measurements were recorded from the photomicrographs at x 100 magnification. There were significant differences between the control group and both test groups. Results of this study show that the presence of the grooves has an adverse effect on the seating of full cast-gold crowns.