Enamel cavosurface bevels finished with ultraspeed instruments.

Rating scores ranked the straight fissure bur first for producing the smoothest and most distinct bevel. The 40-fluted and 12-fluted finishing burs ranked second and third, respectively, and the superfine diamond stone was judged to produce the roughest and least distinct bevel. In selecting an instrument for finishing an external enamel cavosurface bevel, the results of this study suggest that a straight fissure bur will produce the most distinct and smoothest bevel when ultrarotational speeds are used. Results also indicated the superfine diamond stone to be the least desirable instrument for preparing a bevel in enamel.